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  • richardmitnick 9:32 am on November 27, 2021 Permalink | Reply
    Tags: "Super-hot rock" geothermal power, "What Secrets Can The World's 1st Magma Observatory Discover 1 Mile Inside a Volcano?", , , , , Italian National institute for geophysics and volcanology-INGV, KMT: "Krafla Magma Testbed" project, Knowing where the magma is located is vital in order to be prepared for an eruption., Science Alert (US), The KMT is the first magma observatory in the world., The possibility that the operation may trigger a volcanic eruption is something one would naturally worry about.,   

    From The Italian National institute for geophysics and volcanology-INGV via Science Alert (US) : “What Secrets Can The World’s 1st Magma Observatory Discover 1 Mile Inside a Volcano?” 

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    From The Italian National institute for geophysics and volcanology INGV

    via

    ScienceAlert

    Science Alert (US)

    27 NOVEMBER 2021
    JEREMIE RICHARD, AFP

    1
    Krafla seen from Leirhnjúkur in Iceland. (Hansueli Krapf/Wikimedia Commons/CC BY-SA 3.0)

    With its large crater lake of turquoise water, plumes of smoke and sulfurous bubbling of mud and gases, the Krafla volcano is one of Iceland’s most awe-inspiring natural wonders.

    Here, in the country’s northeast, a team of international researchers is preparing to drill two kilometers (1.2 miles) into the heart of the volcano, a Jules Verne-like project aimed at creating the world’s first underground magma observatory.

    Launched in 2014 and with the first drilling due to start in 2024, the $100-million project involves scientists and engineers from 38 research institutes and companies in 11 countries, including the US, Britain, and France.

    The “Krafla Magma Testbed” (KMT) team hopes to drill into the volcano’s magma chamber. Unlike the lava spewed above ground, the molten rock beneath the surface remains a mystery.

    The KMT is the first magma observatory in the world, Paolo Papale, volcanologist at the Italian national institute for geophysics and volcanology INGV, tells Agence France Pressé.com(FR).

    “We have never observed underground magma, apart from fortuitous encounters while drilling” in volcanoes in Hawaii and Kenya, and at Krafla in 2009, he says.

    Scientists hope the project will lead to advances in basic science and so-called “super-hot rock” geothermal power.

    They also hope to further knowledge about volcano prediction and risks.

    “Knowing where the magma is located… is vital” in order to be prepared for an eruption. “Without that, we are nearly blind,” says Papale.

    Not so deep down

    Like many scientific breakthroughs, the magma observatory is the result of an unexpected discovery.

    In 2009, when engineers were expanding Krafla’s geothermal power plant, a bore drill hit a pocket of 900-degree-Celsius (1,650 Fahrenheit) magma by chance, at a depth of 2.1 kilometers.

    Smoke shot up from the borehole and lava flowed nine meters up the well, damaging the drilling material.

    But there was no eruption and no one was hurt.

    Volcanologists realized they were within reach of a magma pocket estimated to contain around 500 million cubic meters.

    Scientists were astonished to find magma this shallow – they had expected to be able to drill to a depth of 4.5 kilometers before that would occur.

    Studies have subsequently shown the magma had similar properties to that from a 1724 eruption, meaning that it was at least 300 years old.

    “This discovery has the potential to be a huge breakthrough in our capability to understand many different things,” ranging from the origin of the continents to volcano dynamics and geothermal systems, Papale enthuses.

    Technically challenging

    The chance find was also auspicious for Landsvirkjun, the national electricity agency that runs the site.

    That close to liquid magma, the rock reaches temperatures so extreme that the fluids are “supercritical”, a state in-between liquid and gas.

    The energy produced there is five to 10 times more powerful than in a conventional borehole.

    During the incident, the steam that rose to the surface was 450C, the highest volcano steam temperature ever recorded.

    Two supercritical wells would be enough to generate the plant’s 60-megawatt capacity currently served by 18 boreholes.

    Landsvirkjun hopes the KMT project will lead to “new technology to be able to drill deeper and to be able to harness this energy that we have not been able to do before,” the head of geothermal operations and resource management, Vordis Eiriksdottir, said.

    But drilling in such an extreme environment is technically challenging. The materials need to be able to resist corrosion caused by the super-hot steam.

    And the possibility that the operation may trigger a volcanic eruption is something “one would naturally worry about”, says John Eichelberger, a University of Alaska-Fairbanks (US) geophysicist and one of the founders of the KMT project.

    But, he says, “this is poking an elephant with a needle.”

    “In total, a dozen holes have hit magma at three different places (in the world) and nothing bad happened.”

    See the full article here.

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    The Italian National institute for geophysics and volcanology INGV is a research institute for geophysics and volcanology in Italy.

    INGV is funded by the Italian Ministry of Education, Universities and Research. Its main responsibilities within the Italian civil protection system are the maintenance and monitoring of the national networks for seismic and volcanic phenomena, together with outreach and educational activities for the Italian population. The institute employs around 2000 people distributed between the headquarters in Rome and the other sections in Milan, Bologna, Pisa, Naples, Catania and Palermo.

    INGV is amongst the top 20 research institutions in terms of scientific publications production. It participates and coordinates several EU research projects and organizes international scientific meetings in collaboration with other institutions.

     
  • richardmitnick 11:35 am on November 26, 2021 Permalink | Reply
    Tags: "Korea's Cutting-Edge Fusion Reactor Just Broke Its Own Record For Containing Plasma", , , China's Experimental Advanced Superconducting Tokamak (EAST), Every test facility does things a little differently using variations on the technology to push the limits., , , KSTAR is one of a handful of test facilities attempting to iron the kinks out of a plasma-wrangling technology called a tokamak., , Science Alert (US), The trick with tokamaks is to fine-tune the current in such a way that it doesn't slip free of its magnetic confines.,   

    From Science Alert (US) : “Korea’s Cutting-Edge Fusion Reactor Just Broke Its Own Record For Containing Plasma” 

    ScienceAlert

    From Science Alert (US)

    26 NOVEMBER 2021
    MIKE MCRAE

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    The KSTAR Tokamak. Credit: KOREA INSTITUTE OF FUSION ENERGY (KR).

    Barely a year after the Korea Superconducting Tokamak Advanced Research (KSTAR project | KOREA INSTITUTE OF FUSION ENERGY [초전도 핵융합연구장치] (KR)) broke one record for fusion, it’s smashed it again, this time holding onto a churning whirlpool of 100 million degree plasma for a whole 30 seconds.

    Though it’s well short of the 101 seconds set by The Chinese Academy of Sciences [中国科学院](CN) earlier this year, it remains a significant milestone on the road to cleaner, near-limitless energy that could transform how we power our society.

    Here’s why it’s so important.

    Deep inside stars like our Sun, gravity and high temperatures give simple elements such as hydrogen the energy they need to overcome the repulsion of their nuclei and force them to squeeze into bigger atoms.

    The result of this nuclear fusion is heavier elements, a few stray neutrons, and a whole lot of heat.

    On Earth, scooping together a Sun’s worth of gravity isn’t possible. But we can achieve similar results by swapping the crunch of gravity for some extra punch in the form of heat. At some point we can even squeeze enough heat from the fusing atoms to keep the nuclear reaction going, with enough left over to siphon off for power.

    That’s the theory. But getting that insanely hot plasma to stay in place long enough to tap into its heat supply for a sustained, reliable source of energy requires some clever thinking.

    The KSTAR is just one of a handful of test facilities around the world attempting to iron the kinks out of a plasma-wrangling technology called a tokamak.

    ITER Tokamak in Saint-Paul-lès-Durance which is in southern France.

    PPPL NSTX-U Tokamak.

    Tokamaks are essentially large metal loops designed to contain clouds of hot, charged particles. Being charged, the moving cloud generates a strong magnetic field, allowing it to be pushed into place by a counter-field.

    The trick with tokamaks is to fine-tune the current in such a way that it doesn’t slip free of its magnetic confines. This is easier said than done, as heated pulses of plasma aren’t so much tornadoes of particles, as unstable, churning maelstroms of chaos.

    Try to contain a loop of jelly inside a ring of rubber bands to get a sense of the challenge.

    There are various other ways to achieve similar results. Stellerators, like Germany’s Wendelstein 7-X test-device, flip the script and use a highly complex, AI-designed tunnel of magnetic coils to keep its churning loop of plasma in place, for example.

    Wendelstein 7-X fusion device at MPG Institute for Plasma Physics (IPP) in Greifswald (DE) 2011.

    This promises a longer hang-time, but makes it a little harder to heat the plasma.

    Tokamaks, on the other hand, have been hitting bigger and bigger temperatures the past few years.

    China’s Experimental Advanced Superconducting Tokamak (EAST) reactor in Hefei became the first to hit a significant temperature landmark of 100 million degrees Celsius back in 2018, a temperature that’s still out of reach of stellerators (for now).

    China – Experimental Advanced Superconducting Tokamak (EAST) reactor

    This year, EAST heated plasma to 120 million degrees Celsius, holding it for more than a minute and a half.

    Those temperatures, however, were a measure of the energy shared among its electrons. Hot, no question, but getting the temperature of the much heavier ions to increase is also important. Not to mention harder.

    The KSTAR hit 100 million for its ion temperature last year, maintaining the pulse for 20 seconds.

    The fact it’s just hit 30 seconds – a little over 12 months later – is incredibly encouraging.

    Every test facility does things a little differently using variations on the technology to push the limits on anything from pulse duration to stability to electron or plasma temperature.

    While it’s tempting to see each record as a competition, it’s important to celebrate every milestone as one more lesson learned.

    Every achievement shows others ways to deal with the hurdles we still face in harnessing the Sun’s engine into a powerhouse on Earth.

    See the full article here .


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  • richardmitnick 10:56 am on November 26, 2021 Permalink | Reply
    Tags: "We All Nearly Missed The Largest Underwater Volcano Eruption Ever Detected", A raft of floating rock spewed from an underwater volcano, An underwater volcano called the Havre Seamount, , , , , Science Alert (US),   

    From Science Alert (US) : “We All Nearly Missed The Largest Underwater Volcano Eruption Ever Detected” 

    ScienceAlert

    From Science Alert (US)

    26 NOVEMBER 2021
    PETER DOCKRILL

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    Credit: Rebecca Carey, The University of Tasmania (AU)/Adam Soule, The Woods Hole Oceanographic Institution (US))

    She was flying home from a holiday in Samoa when she saw it through the airplane window: a “peculiar large mass” floating on the ocean, hundreds of kilometres off the north coast of New Zealand.

    The Kiwi passenger emailed photos of the strange ocean slick to scientists, who realized what it was – a raft of floating rock spewed from an underwater volcano, produced in the largest eruption of its kind ever recorded.

    “We knew it was a large-scale eruption, approximately equivalent to the biggest eruption we’ve seen on land in the 20th Century,” said volcanologist Rebecca Carey from The University of Tasmania (AU), who co-led the first close-up investigation of the historic 2012 eruption, and together with colleagues finally published the results in a paper in 2018.

    The incident, produced by an underwater volcano called the Havre Seamount, initially went unnoticed by scientists, but the floating rock platform it generated was harder to miss.

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    High-resolution seafloor topography of the Havre caldera. Credit: Rebecca Carey, University of Tasmania/Adam Soule, WHOI.

    Back in 2012, the raft – composed of pumice, a type of very light, air-filled volcanic rock – covered some 400 square kilometres (154 square miles) of the south-west Pacific Ocean, but months later satellites recorded it dispersing over an area twice the size of New Zealand itself.

    Under the surface, the sheer scale of the rocky aftermath took scientists aback when they inspected the site in 2015, at depths as low as 1,220 metres (4,000 feet).

    “When we looked at the detailed maps from the AUV [autonomous underwater vehicle], we saw all these bumps on the seafloor and I thought the vehicle’s sonar was acting up,” said volcanologist Adam Soule from The Woods Hole Oceanographic Institution (US).

    “It turned out that each bump was a giant block of pumice, some of them the size of a van. I had never seen anything like it on the seafloor.”

    The investigation – conducted with the AUV Sentry and the remotely operated vehicle (ROV) Jason – reveals that Havre Seamount’s eruption was more complex than anyone topside ever knew.

    A close-up Look at a Rare Underwater Eruption.Credit WHOI.

    The caldera, which spans nearly 4.5 kilometres (about 3 miles), discharged lava from some 14 vents in a “massive rupture of the volcanic edifice”, producing not just pumice rock, but ash, lava domes, and seafloor lava flows.

    It may have been (thankfully) buried under an ocean of water, but for a sense of scale, think roughly 1.5 times larger than the 1980 eruption of Mount St. Helens – or 10 times the size of the 2010 Eyjafjallajökull eruption in Iceland.

    The researchers say that of the material erupted, three-quarters or more floated to the surface and drifted away – tonnes of it washing up onto shorelines an ocean away.

    The rest of it was scattered around the nearby seafloor, bringing devastation to the biological communities who called it home, and are only now rebounding.

    “The record of this eruption on Havre volcano itself is highly unfaithful,” said Carey.

    “[I]t preserves a small component of what was actually produced, which is important for how we interpret ancient submarine volcanic successions that are now uplifted and are highly prospective for metals and minerals.”

    With samples collected by the submersibles yielding what the scientists say could amount to a decade’s worth of research, it’s a huge, rare opportunity to study what takes place when a volcano erupts under the sea – a phenomenon that actually accounts for more than 70 percent of all volcanism on Earth, even if it’s a bit harder to spot.

    “Underwater eruptions are fundamentally different than those on land,” noted one of the team, geophysicist Michael Manga from The University of California-Berkeley (US).

    “There is no on-land equivalent.”

    The findings were reported in Science Advances.

    A version of this article was originally published in January 2018.

    See the full article here .


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  • richardmitnick 11:30 am on November 23, 2021 Permalink | Reply
    Tags: "This New Hubble Pic Reveals a Dramatic Cosmic Phenomenon in All Its Gory Detail", A protostar named J1672835.29-763111.64., , , , , , Science Alert (US), Stars form in cool dense clouds of interstellar molecular gas., The Chamaeleon complex-full of very young newly formed T Tauri stars.   

    From Hubblesite (US) and ESA Hubble via Science Alert (US) : “This New Hubble Pic Reveals a Dramatic Cosmic Phenomenon in All Its Gory Detail” 

    National Aeronautics and Space Administration(US)/European Space Agency [Agence spatiale européenne] [Europäische Weltraumorganisation](EU) Hubble Space Telescope.

    From Hubblesite (US) and ESA Hubble

    via

    ScienceAlert

    Science Alert (US)

    22 NOVEMBER 2021
    MICHELLE STARR

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    (The National Aeronautics and Space Agency(US), The European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU), T. Megeath/The University of Toledo(US), K. Stapelfeldt/JPL/Caltech-NASA (US), Gladys Kober/NASA/The Catholic University of America (US)).

    The fire and fury of the birth of a star is captured in an exquisite new image from the Hubble space telescope.

    Roughly 400 to 600 or so light-years away, in the southern constellation of Chamaeleon, a large complex of clouds is transforming into stars. This is called the Chamaeleon complex; it’s full of very young newly formed T Tauri stars.

    If you look closely with the right instruments, you can also see stars that are in the process of forming, known as protostars. The subject of Hubble’s new photo is one of these, named J1672835.29-763111.64, embedded in the reflection nebula IC 2631 (that’s a nebula that shines with reflected starlight; IC 2631 is lit by a star named HD 97300).

    Stars form in cool dense clouds of interstellar molecular gas. This gas is not evenly distributed; denser clumps can coalesce due to processes such as local stellar winds, which push the gas together. When the density is high enough, these clumps can collapse under their own gravity, forming a spinning protostar.

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    A detailed close-up of protostar J1672835.29-763111.64. (NASA, ESA, T. Megeath/U Toledo, K. Stapelfeldt/JPL, Gladys Kober/NASA/CUA).

    As a protostar spins, material in the cloud around the object forms a disk. This disk of material spools into the forming star, drawn in by its strengthening gravity, which grows as the protostar gains mass.

    As the protostar grows, it starts to produce a powerful stellar wind, and material falling into the protostar starts to interact with its magnetic fields, flowing along magnetic field lines to the poles, where it is blasted into space in the form of powerful plasma jets.

    The wind and jets are known as stellar feedback, and they help to blow away material from around the protostar, slowing and eventually cutting off its growth. When the star gains enough mass to produce sufficient heat and pressure in the core, nuclear fusion will kick off – et voila, your star is now on the main sequence.

    Whatever gas and dust is left over in the disk will then form other objects such as planets, asteroids, and comets. That’s why the Solar System’s planets and asteroid belt are arranged more or less on a flat plane.

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    J1672835.29-763111.64 next to reflection nebula IC 2631. (NASA, ESA, T. Megeath/U Toledo, K. Stapelfeldt/JPL, Gladys Kober/NASA/CUA).

    Protostar J1672835.29-763111.64 is not quite at that point yet. The region around it is still very dusty, which means it hasn’t yet blown away the material around it.

    Usually, we wouldn’t be able to see the protostar glowing amidst all that dust, but infrared wavelengths can penetrate the cloud, which means Hubble’s infrared instrument can see it.

    The protostar was observed as part of a survey targeting 312 such objects, obscured by dense molecular clouds. Star formation is a relatively long process on human timescales, taking place over millions of years, which means we will likely never be able to see it from start to finish.

    We can learn more about it by identifying as many protostars as we can find, and obtaining as much information on them as we can. Clever astronomers then study the process by using these stars to work out a star formation timeline, and studying each of the stages in detail.

    So J1672835.29-763111.64 is more than just a snapshot of an amazing phenomenon. It will join other protostars in Hubble’s survey to contribute towards building a more holistic and detailed model of how the incredible process of star formation unfolds.

    See the full article here .

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    The NASA/ESA Hubble Space Telescope is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, renowned both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA’s Great Observatories, along with the NASA Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the NASA Spitzer Infared Space Telescope.

    National Aeronautics Space Agency(USA) Compton Gamma Ray Observatory
    National Aeronautics and Space Administration(US) Chandra X-ray telescope(US).
    National Aeronautics and Space Administration(US) Spitzer Infrared Apace Telescope no longer in service. Launched in 2003 and retired on 30 January 2020.

    Edwin Hubble at Caltech Palomar Samuel Oschin 48 inch Telescope(US) Credit: Emilio Segre Visual Archives/AIP/SPL.

    Edwin Hubble looking through the 100-inch Hooker telescope at Mount Wilson in Southern California(US), 1929 discovers the Universe is Expanding.Credit: Margaret Bourke-White/Time & Life Pictures/Getty Images.

    Hubble features a 2.4-meter (7.9 ft) mirror, and its four main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble’s orbit outside the distortion of Earth’s atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detailed visible light images, allowing a deep view into space. Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe.

    The Hubble telescope was built by the United States space agency National Aeronautics Space Agency(US) with contributions from the European Space Agency [Agence spatiale européenne](EU). The Space Telescope Science Institute (STScI) selects Hubble’s targets and processes the resulting data, while the NASA Goddard Space Flight Center(US) controls the spacecraft. Space telescopes were proposed as early as 1923. Hubble was funded in the 1970s with a proposed launch in 1983, but the project was beset by technical delays, budget problems, and the 1986 Challenger disaster. It was finally launched by Space Shuttle Discovery in 1990, but its main mirror had been ground incorrectly, resulting in spherical aberration that compromised the telescope’s capabilities. The optics were corrected to their intended quality by a servicing mission in 1993.

    Hubble is the only telescope designed to be maintained in space by astronauts. Five Space Shuttle missions have repaired, upgraded, and replaced systems on the telescope, including all five of the main instruments. The fifth mission was initially canceled on safety grounds following the Columbia disaster (2003), but NASA administrator Michael D. Griffin approved the fifth servicing mission which was completed in 2009. The telescope was still operating as of April 24, 2020, its 30th anniversary, and could last until 2030–2040. One successor to the Hubble telescope is the National Aeronautics Space Agency(USA)/European Space Agency [Agence spatiale européenne](EU)/Canadian Space Agency(CA) Webb Infrared Space Telescope scheduled for launch in December 2021.

    National Aeronautics Space Agency(USA)/European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU)/ Canadian Space Agency [Agence Spatiale Canadienne](CA) Webb Infrared Space Telescope(US) James Webb Space Telescope annotated. Scheduled for launch in October 2021 delayed to December 2021.

    Proposals and precursors

    In 1923, Hermann Oberth—considered a father of modern rocketry, along with Robert H. Goddard and Konstantin Tsiolkovsky—published Die Rakete zu den Planetenräumen (“The Rocket into Planetary Space“), which mentioned how a telescope could be propelled into Earth orbit by a rocket.

    The history of the Hubble Space Telescope can be traced back as far as 1946, to astronomer Lyman Spitzer’s paper entitled Astronomical advantages of an extraterrestrial observatory. In it, he discussed the two main advantages that a space-based observatory would have over ground-based telescopes. First, the angular resolution (the smallest separation at which objects can be clearly distinguished) would be limited only by diffraction, rather than by the turbulence in the atmosphere, which causes stars to twinkle, known to astronomers as seeing. At that time ground-based telescopes were limited to resolutions of 0.5–1.0 arcseconds, compared to a theoretical diffraction-limited resolution of about 0.05 arcsec for an optical telescope with a mirror 2.5 m (8.2 ft) in diameter. Second, a space-based telescope could observe infrared and ultraviolet light, which are strongly absorbed by the atmosphere.

    Spitzer devoted much of his career to pushing for the development of a space telescope. In 1962, a report by the U.S. National Academy of Sciences recommended development of a space telescope as part of the space program, and in 1965 Spitzer was appointed as head of a committee given the task of defining scientific objectives for a large space telescope.

    Space-based astronomy had begun on a very small scale following World War II, as scientists made use of developments that had taken place in rocket technology. The first ultraviolet spectrum of the Sun was obtained in 1946, and the National Aeronautics and Space Administration (US) launched the Orbiting Solar Observatory (OSO) to obtain UV, X-ray, and gamma-ray spectra in 1962.
    National Aeronautics Space Agency(USA) Orbiting Solar Observatory

    An orbiting solar telescope was launched in 1962 by the United Kingdom as part of the Ariel space program, and in 1966 NASA launched the first Orbiting Astronomical Observatory (OAO) mission. OAO-1’s battery failed after three days, terminating the mission. It was followed by OAO-2, which carried out ultraviolet observations of stars and galaxies from its launch in 1968 until 1972, well beyond its original planned lifetime of one year.

    The OSO and OAO missions demonstrated the important role space-based observations could play in astronomy. In 1968, NASA developed firm plans for a space-based reflecting telescope with a mirror 3 m (9.8 ft) in diameter, known provisionally as the Large Orbiting Telescope or Large Space Telescope (LST), with a launch slated for 1979. These plans emphasized the need for crewed maintenance missions to the telescope to ensure such a costly program had a lengthy working life, and the concurrent development of plans for the reusable Space Shuttle indicated that the technology to allow this was soon to become available.

    Quest for funding

    The continuing success of the OAO program encouraged increasingly strong consensus within the astronomical community that the LST should be a major goal. In 1970, NASA established two committees, one to plan the engineering side of the space telescope project, and the other to determine the scientific goals of the mission. Once these had been established, the next hurdle for NASA was to obtain funding for the instrument, which would be far more costly than any Earth-based telescope. The U.S. Congress questioned many aspects of the proposed budget for the telescope and forced cuts in the budget for the planning stages, which at the time consisted of very detailed studies of potential instruments and hardware for the telescope. In 1974, public spending cuts led to Congress deleting all funding for the telescope project.
    In response a nationwide lobbying effort was coordinated among astronomers. Many astronomers met congressmen and senators in person, and large scale letter-writing campaigns were organized. The National Academy of Sciences published a report emphasizing the need for a space telescope, and eventually the Senate agreed to half the budget that had originally been approved by Congress.

    The funding issues led to something of a reduction in the scale of the project, with the proposed mirror diameter reduced from 3 m to 2.4 m, both to cut costs and to allow a more compact and effective configuration for the telescope hardware. A proposed precursor 1.5 m (4.9 ft) space telescope to test the systems to be used on the main satellite was dropped, and budgetary concerns also prompted collaboration with the European Space Agency. ESA agreed to provide funding and supply one of the first generation instruments for the telescope, as well as the solar cells that would power it, and staff to work on the telescope in the United States, in return for European astronomers being guaranteed at least 15% of the observing time on the telescope. Congress eventually approved funding of US$36 million for 1978, and the design of the LST began in earnest, aiming for a launch date of 1983. In 1983 the telescope was named after Edwin Hubble, who confirmed one of the greatest scientific discoveries of the 20th century, made by Georges Lemaître, that the universe is expanding.

    Construction and engineering

    Once the Space Telescope project had been given the go-ahead, work on the program was divided among many institutions. NASA Marshall Space Flight Center (MSFC) was given responsibility for the design, development, and construction of the telescope, while Goddard Space Flight Center was given overall control of the scientific instruments and ground-control center for the mission. MSFC commissioned the optics company Perkin-Elmer to design and build the Optical Telescope Assembly (OTA) and Fine Guidance Sensors for the space telescope. Lockheed was commissioned to construct and integrate the spacecraft in which the telescope would be housed.

    Optical Telescope Assembly

    Optically, the HST is a Cassegrain reflector of Ritchey–Chrétien design, as are most large professional telescopes. This design, with two hyperbolic mirrors, is known for good imaging performance over a wide field of view, with the disadvantage that the mirrors have shapes that are hard to fabricate and test. The mirror and optical systems of the telescope determine the final performance, and they were designed to exacting specifications. Optical telescopes typically have mirrors polished to an accuracy of about a tenth of the wavelength of visible light, but the Space Telescope was to be used for observations from the visible through the ultraviolet (shorter wavelengths) and was specified to be diffraction limited to take full advantage of the space environment. Therefore, its mirror needed to be polished to an accuracy of 10 nanometers, or about 1/65 of the wavelength of red light. On the long wavelength end, the OTA was not designed with optimum IR performance in mind—for example, the mirrors are kept at stable (and warm, about 15 °C) temperatures by heaters. This limits Hubble’s performance as an infrared telescope.

    Perkin-Elmer intended to use custom-built and extremely sophisticated computer-controlled polishing machines to grind the mirror to the required shape. However, in case their cutting-edge technology ran into difficulties, NASA demanded that PE sub-contract to Kodak to construct a back-up mirror using traditional mirror-polishing techniques. (The team of Kodak and Itek also bid on the original mirror polishing work. Their bid called for the two companies to double-check each other’s work, which would have almost certainly caught the polishing error that later caused such problems.) The Kodak mirror is now on permanent display at the National Air and Space Museum. An Itek mirror built as part of the effort is now used in the 2.4 m telescope at the Magdalena Ridge Observatory.

    Construction of the Perkin-Elmer mirror began in 1979, starting with a blank manufactured by Corning from their ultra-low expansion glass. To keep the mirror’s weight to a minimum it consisted of top and bottom plates, each one inch (25 mm) thick, sandwiching a honeycomb lattice. Perkin-Elmer simulated microgravity by supporting the mirror from the back with 130 rods that exerted varying amounts of force. This ensured the mirror’s final shape would be correct and to specification when finally deployed. Mirror polishing continued until May 1981. NASA reports at the time questioned Perkin-Elmer’s managerial structure, and the polishing began to slip behind schedule and over budget. To save money, NASA halted work on the back-up mirror and put the launch date of the telescope back to October 1984. The mirror was completed by the end of 1981; it was washed using 2,400 US gallons (9,100 L) of hot, deionized water and then received a reflective coating of 65 nm-thick aluminum and a protective coating of 25 nm-thick magnesium fluoride.

    Doubts continued to be expressed about Perkin-Elmer’s competence on a project of this importance, as their budget and timescale for producing the rest of the OTA continued to inflate. In response to a schedule described as “unsettled and changing daily”, NASA postponed the launch date of the telescope until April 1985. Perkin-Elmer’s schedules continued to slip at a rate of about one month per quarter, and at times delays reached one day for each day of work. NASA was forced to postpone the launch date until March and then September 1986. By this time, the total project budget had risen to US$1.175 billion.

    Spacecraft systems

    The spacecraft in which the telescope and instruments were to be housed was another major engineering challenge. It would have to withstand frequent passages from direct sunlight into the darkness of Earth’s shadow, which would cause major changes in temperature, while being stable enough to allow extremely accurate pointing of the telescope. A shroud of multi-layer insulation keeps the temperature within the telescope stable and surrounds a light aluminum shell in which the telescope and instruments sit. Within the shell, a graphite-epoxy frame keeps the working parts of the telescope firmly aligned. Because graphite composites are hygroscopic, there was a risk that water vapor absorbed by the truss while in Lockheed’s clean room would later be expressed in the vacuum of space; resulting in the telescope’s instruments being covered by ice. To reduce that risk, a nitrogen gas purge was performed before launching the telescope into space.

    While construction of the spacecraft in which the telescope and instruments would be housed proceeded somewhat more smoothly than the construction of the OTA, Lockheed still experienced some budget and schedule slippage, and by the summer of 1985, construction of the spacecraft was 30% over budget and three months behind schedule. An MSFC report said Lockheed tended to rely on NASA directions rather than take their own initiative in the construction.

    Computer systems and data processing

    The two initial, primary computers on the HST were the 1.25 MHz DF-224 system, built by Rockwell Autonetics, which contained three redundant CPUs, and two redundant NSSC-1 (NASA Standard Spacecraft Computer, Model 1) systems, developed by Westinghouse and GSFC using diode–transistor logic (DTL). A co-processor for the DF-224 was added during Servicing Mission 1 in 1993, which consisted of two redundant strings of an Intel-based 80386 processor with an 80387 math co-processor. The DF-224 and its 386 co-processor were replaced by a 25 MHz Intel-based 80486 processor system during Servicing Mission 3A in 1999. The new computer is 20 times faster, with six times more memory, than the DF-224 it replaced. It increases throughput by moving some computing tasks from the ground to the spacecraft and saves money by allowing the use of modern programming languages.

    Additionally, some of the science instruments and components had their own embedded microprocessor-based control systems. The MATs (Multiple Access Transponder) components, MAT-1 and MAT-2, utilize Hughes Aircraft CDP1802CD microprocessors. The Wide Field and Planetary Camera (WFPC) also utilized an RCA 1802 microprocessor (or possibly the older 1801 version). The WFPC-1 was replaced by the WFPC-2 [below] during Servicing Mission 1 in 1993, which was then replaced by the Wide Field Camera 3 (WFC3) [below] during Servicing Mission 4 in 2009.

    Initial instruments

    When launched, the HST carried five scientific instruments: the Wide Field and Planetary Camera (WF/PC), Goddard High Resolution Spectrograph (GHRS), High Speed Photometer (HSP), Faint Object Camera (FOC) and the Faint Object Spectrograph (FOS). WF/PC was a high-resolution imaging device primarily intended for optical observations. It was built by NASA JPL-Caltech(US), and incorporated a set of 48 filters isolating spectral lines of particular astrophysical interest. The instrument contained eight charge-coupled device (CCD) chips divided between two cameras, each using four CCDs. Each CCD has a resolution of 0.64 megapixels. The wide field camera (WFC) covered a large angular field at the expense of resolution, while the planetary camera (PC) took images at a longer effective focal length than the WF chips, giving it a greater magnification.

    The GHRS was a spectrograph designed to operate in the ultraviolet. It was built by the Goddard Space Flight Center and could achieve a spectral resolution of 90,000. Also optimized for ultraviolet observations were the FOC and FOS, which were capable of the highest spatial resolution of any instruments on Hubble. Rather than CCDs these three instruments used photon-counting digicons as their detectors. The FOC was constructed by ESA, while the University of California, San Diego(US), and Martin Marietta Corporation built the FOS.

    The final instrument was the HSP, designed and built at the University of Wisconsin–Madison(US). It was optimized for visible and ultraviolet light observations of variable stars and other astronomical objects varying in brightness. It could take up to 100,000 measurements per second with a photometric accuracy of about 2% or better.

    HST’s guidance system can also be used as a scientific instrument. Its three Fine Guidance Sensors (FGS) are primarily used to keep the telescope accurately pointed during an observation, but can also be used to carry out extremely accurate astrometry; measurements accurate to within 0.0003 arcseconds have been achieved.

    Ground support

    The Space Telescope Science Institute (STScI) is responsible for the scientific operation of the telescope and the delivery of data products to astronomers. STScI is operated by the Association of Universities for Research in Astronomy (US) (AURA) and is physically located in Baltimore, Maryland on the Homewood campus of Johns Hopkins University (US), one of the 39 U.S. universities and seven international affiliates that make up the AURA consortium. STScI was established in 1981 after something of a power struggle between NASA and the scientific community at large. NASA had wanted to keep this function in-house, but scientists wanted it to be based in an academic establishment. The Space Telescope European Coordinating Facility (ST-ECF), established at Garching bei München near Munich in 1984, provided similar support for European astronomers until 2011, when these activities were moved to the European Space Astronomy Centre.

    One rather complex task that falls to STScI is scheduling observations for the telescope. Hubble is in a low-Earth orbit to enable servicing missions, but this means most astronomical targets are occulted by the Earth for slightly less than half of each orbit. Observations cannot take place when the telescope passes through the South Atlantic Anomaly due to elevated radiation levels, and there are also sizable exclusion zones around the Sun (precluding observations of Mercury), Moon and Earth. The solar avoidance angle is about 50°, to keep sunlight from illuminating any part of the OTA. Earth and Moon avoidance keeps bright light out of the FGSs, and keeps scattered light from entering the instruments. If the FGSs are turned off, the Moon and Earth can be observed. Earth observations were used very early in the program to generate flat-fields for the WFPC1 instrument. There is a so-called continuous viewing zone (CVZ), at roughly 90° to the plane of Hubble’s orbit, in which targets are not occulted for long periods.

    Challenger disaster, delays, and eventual launch

    By January 1986, the planned launch date of October looked feasible, but the Challenger explosion brought the U.S. space program to a halt, grounding the Shuttle fleet and forcing the launch of Hubble to be postponed for several years. The telescope had to be kept in a clean room, powered up and purged with nitrogen, until a launch could be rescheduled. This costly situation (about US$6 million per month) pushed the overall costs of the project even higher. This delay did allow time for engineers to perform extensive tests, swap out a possibly failure-prone battery, and make other improvements. Furthermore, the ground software needed to control Hubble was not ready in 1986, and was barely ready by the 1990 launch.

    Eventually, following the resumption of shuttle flights in 1988, the launch of the telescope was scheduled for 1990. On April 24, 1990, Space Shuttle Discovery successfully launched it during the STS-31 mission.

    From its original total cost estimate of about US$400 million, the telescope cost about US$4.7 billion by the time of its launch. Hubble’s cumulative costs were estimated to be about US$10 billion in 2010, twenty years after launch.

    List of Hubble instruments

    Hubble accommodates five science instruments at a given time, plus the Fine Guidance Sensors, which are mainly used for aiming the telescope but are occasionally used for scientific astrometry measurements. Early instruments were replaced with more advanced ones during the Shuttle servicing missions. COSTAR was a corrective optics device rather than a science instrument, but occupied one of the five instrument bays.
    Since the final servicing mission in 2009, the four active instruments have been ACS, COS, STIS and WFC3. NICMOS is kept in hibernation, but may be revived if WFC3 were to fail in the future.

    Advanced Camera for Surveys (ACS; 2002–present)
    Cosmic Origins Spectrograph (COS; 2009–present)
    Corrective Optics Space Telescope Axial Replacement (COSTAR; 1993–2009)
    Faint Object Camera (FOC; 1990–2002)
    Faint Object Spectrograph (FOS; 1990–1997)
    Fine Guidance Sensor (FGS; 1990–present)
    Goddard High Resolution Spectrograph (GHRS/HRS; 1990–1997)
    High Speed Photometer (HSP; 1990–1993)
    Near Infrared Camera and Multi-Object Spectrometer (NICMOS; 1997–present, hibernating since 2008)
    Space Telescope Imaging Spectrograph (STIS; 1997–present (non-operative 2004–2009))
    Wide Field and Planetary Camera (WFPC; 1990–1993)
    Wide Field and Planetary Camera 2 (WFPC2; 1993–2009)
    Wide Field Camera 3 (WFC3; 2009–present)

    Of the former instruments, three (COSTAR, FOS and WFPC2) are displayed in the Smithsonian National Air and Space Museum. The FOC is in the Dornier museum, Germany. The HSP is in the Space Place at the University of Wisconsin–Madison. The first WFPC was dismantled, and some components were then re-used in WFC3.

    Flawed mirror

    Within weeks of the launch of the telescope, the returned images indicated a serious problem with the optical system. Although the first images appeared to be sharper than those of ground-based telescopes, Hubble failed to achieve a final sharp focus and the best image quality obtained was drastically lower than expected. Images of point sources spread out over a radius of more than one arcsecond, instead of having a point spread function (PSF) concentrated within a circle 0.1 arcseconds (485 nrad) in diameter, as had been specified in the design criteria.

    Analysis of the flawed images revealed that the primary mirror had been polished to the wrong shape. Although it was believed to be one of the most precisely figured optical mirrors ever made, smooth to about 10 nanometers, the outer perimeter was too flat by about 2200 nanometers (about 1⁄450 mm or 1⁄11000 inch). This difference was catastrophic, introducing severe spherical aberration, a flaw in which light reflecting off the edge of a mirror focuses on a different point from the light reflecting off its center.

    The effect of the mirror flaw on scientific observations depended on the particular observation—the core of the aberrated PSF was sharp enough to permit high-resolution observations of bright objects, and spectroscopy of point sources was affected only through a sensitivity loss. However, the loss of light to the large, out-of-focus halo severely reduced the usefulness of the telescope for faint objects or high-contrast imaging. This meant nearly all the cosmological programs were essentially impossible, since they required observation of exceptionally faint objects. This led politicians to question NASA’s competence, scientists to rue the cost which could have gone to more productive endeavors, and comedians to make jokes about NASA and the telescope − in the 1991 comedy The Naked Gun 2½: The Smell of Fear, in a scene where historical disasters are displayed, Hubble is pictured with RMS Titanic and LZ 129 Hindenburg. Nonetheless, during the first three years of the Hubble mission, before the optical corrections, the telescope still carried out a large number of productive observations of less demanding targets. The error was well characterized and stable, enabling astronomers to partially compensate for the defective mirror by using sophisticated image processing techniques such as deconvolution.

    Origin of the problem

    A commission headed by Lew Allen, director of the Jet Propulsion Laboratory, was established to determine how the error could have arisen. The Allen Commission found that a reflective null corrector, a testing device used to achieve a properly shaped non-spherical mirror, had been incorrectly assembled—one lens was out of position by 1.3 mm (0.051 in). During the initial grinding and polishing of the mirror, Perkin-Elmer analyzed its surface with two conventional refractive null correctors. However, for the final manufacturing step (figuring), they switched to the custom-built reflective null corrector, designed explicitly to meet very strict tolerances. The incorrect assembly of this device resulted in the mirror being ground very precisely but to the wrong shape. A few final tests, using the conventional null correctors, correctly reported spherical aberration. But these results were dismissed, thus missing the opportunity to catch the error, because the reflective null corrector was considered more accurate.

    The commission blamed the failings primarily on Perkin-Elmer. Relations between NASA and the optics company had been severely strained during the telescope construction, due to frequent schedule slippage and cost overruns. NASA found that Perkin-Elmer did not review or supervise the mirror construction adequately, did not assign its best optical scientists to the project (as it had for the prototype), and in particular did not involve the optical designers in the construction and verification of the mirror. While the commission heavily criticized Perkin-Elmer for these managerial failings, NASA was also criticized for not picking up on the quality control shortcomings, such as relying totally on test results from a single instrument.

    Design of a solution

    Many feared that Hubble would be abandoned. The design of the telescope had always incorporated servicing missions, and astronomers immediately began to seek potential solutions to the problem that could be applied at the first servicing mission, scheduled for 1993. While Kodak had ground a back-up mirror for Hubble, it would have been impossible to replace the mirror in orbit, and too expensive and time-consuming to bring the telescope back to Earth for a refit. Instead, the fact that the mirror had been ground so precisely to the wrong shape led to the design of new optical components with exactly the same error but in the opposite sense, to be added to the telescope at the servicing mission, effectively acting as “spectacles” to correct the spherical aberration.

    The first step was a precise characterization of the error in the main mirror. Working backwards from images of point sources, astronomers determined that the conic constant of the mirror as built was −1.01390±0.0002, instead of the intended −1.00230. The same number was also derived by analyzing the null corrector used by Perkin-Elmer to figure the mirror, as well as by analyzing interferograms obtained during ground testing of the mirror.

    Because of the way the HST’s instruments were designed, two different sets of correctors were required. The design of the Wide Field and Planetary Camera 2, already planned to replace the existing WF/PC, included relay mirrors to direct light onto the four separate charge-coupled device (CCD) chips making up its two cameras. An inverse error built into their surfaces could completely cancel the aberration of the primary. However, the other instruments lacked any intermediate surfaces that could be figured in this way, and so required an external correction device.

    The Corrective Optics Space Telescope Axial Replacement (COSTAR) system was designed to correct the spherical aberration for light focused at the FOC, FOS, and GHRS. It consists of two mirrors in the light path with one ground to correct the aberration. To fit the COSTAR system onto the telescope, one of the other instruments had to be removed, and astronomers selected the High Speed Photometer to be sacrificed. By 2002, all the original instruments requiring COSTAR had been replaced by instruments with their own corrective optics. COSTAR was removed and returned to Earth in 2009 where it is exhibited at the National Air and Space Museum. The area previously used by COSTAR is now occupied by the Cosmic Origins Spectrograph.

    Servicing missions and new instruments

    Servicing Mission 1

    The first Hubble serving mission was scheduled for 1993 before the mirror problem was discovered. It assumed greater importance, as the astronauts would need to do extensive work to install corrective optics; failure would have resulted in either abandoning Hubble or accepting its permanent disability. Other components failed before the mission, causing the repair cost to rise to $500 million (not including the cost of the shuttle flight). A successful repair would help demonstrate the viability of building Space Station Alpha, however.

    STS-49 in 1992 demonstrated the difficulty of space work. While its rescue of Intelsat 603 received praise, the astronauts had taken possibly reckless risks in doing so. Neither the rescue nor the unrelated assembly of prototype space station components occurred as the astronauts had trained, causing NASA to reassess planning and training, including for the Hubble repair. The agency assigned to the mission Story Musgrave—who had worked on satellite repair procedures since 1976—and six other experienced astronauts, including two from STS-49. The first mission director since Project Apollo would coordinate a crew with 16 previous shuttle flights. The astronauts were trained to use about a hundred specialized tools.

    Heat had been the problem on prior spacewalks, which occurred in sunlight. Hubble needed to be repaired out of sunlight. Musgrave discovered during vacuum training, seven months before the mission, that spacesuit gloves did not sufficiently protect against the cold of space. After STS-57 confirmed the issue in orbit, NASA quickly changed equipment, procedures, and flight plan. Seven total mission simulations occurred before launch, the most thorough preparation in shuttle history. No complete Hubble mockup existed, so the astronauts studied many separate models (including one at the Smithsonian) and mentally combined their varying and contradictory details. Service Mission 1 flew aboard Endeavour in December 1993, and involved installation of several instruments and other equipment over ten days.

    Most importantly, the High Speed Photometer was replaced with the COSTAR corrective optics package, and WFPC was replaced with the Wide Field and Planetary Camera 2 (WFPC2) with an internal optical correction system. The solar arrays and their drive electronics were also replaced, as well as four gyroscopes in the telescope pointing system, two electrical control units and other electrical components, and two magnetometers. The onboard computers were upgraded with added coprocessors, and Hubble’s orbit was boosted.

    On January 13, 1994, NASA declared the mission a complete success and showed the first sharper images. The mission was one of the most complex performed up until that date, involving five long extra-vehicular activity periods. Its success was a boon for NASA, as well as for the astronomers who now had a more capable space telescope.

    Servicing Mission 2

    Servicing Mission 2, flown by Discovery in February 1997, replaced the GHRS and the FOS with the Space Telescope Imaging Spectrograph (STIS) and the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), replaced an Engineering and Science Tape Recorder with a new Solid State Recorder, and repaired thermal insulation. NICMOS contained a heat sink of solid nitrogen to reduce the thermal noise from the instrument, but shortly after it was installed, an unexpected thermal expansion resulted in part of the heat sink coming into contact with an optical baffle. This led to an increased warming rate for the instrument and reduced its original expected lifetime of 4.5 years to about two years.

    Servicing Mission 3A

    Servicing Mission 3A, flown by Discovery, took place in December 1999, and was a split-off from Servicing Mission 3 after three of the six onboard gyroscopes had failed. The fourth failed a few weeks before the mission, rendering the telescope incapable of performing scientific observations. The mission replaced all six gyroscopes, replaced a Fine Guidance Sensor and the computer, installed a Voltage/temperature Improvement Kit (VIK) to prevent battery overcharging, and replaced thermal insulation blankets.

    Servicing Mission 3B

    Servicing Mission 3B flown by Columbia in March 2002 saw the installation of a new instrument, with the FOC (which, except for the Fine Guidance Sensors when used for astrometry, was the last of the original instruments) being replaced by the Advanced Camera for Surveys (ACS). This meant COSTAR was no longer required, since all new instruments had built-in correction for the main mirror aberration. The mission also revived NICMOS by installing a closed-cycle cooler and replaced the solar arrays for the second time, providing 30 percent more power.

    Servicing Mission 4

    Plans called for Hubble to be serviced in February 2005, but the Columbia disaster in 2003, in which the orbiter disintegrated on re-entry into the atmosphere, had wide-ranging effects on the Hubble program. NASA Administrator Sean O’Keefe decided all future shuttle missions had to be able to reach the safe haven of the International Space Station should in-flight problems develop. As no shuttles were capable of reaching both HST and the space station during the same mission, future crewed service missions were canceled. This decision was criticised by numerous astronomers who felt Hubble was valuable enough to merit the human risk. HST’s planned successor, the James Webb Telescope (JWST), as of 2004 was not expected to launch until at least 2011. A gap in space-observing capabilities between a decommissioning of Hubble and the commissioning of a successor was of major concern to many astronomers, given the significant scientific impact of HST. The consideration that JWST will not be located in low Earth orbit, and therefore cannot be easily upgraded or repaired in the event of an early failure, only made concerns more acute. On the other hand, many astronomers felt strongly that servicing Hubble should not take place if the expense were to come from the JWST budget.

    In January 2004, O’Keefe said he would review his decision to cancel the final servicing mission to HST, due to public outcry and requests from Congress for NASA to look for a way to save it. The National Academy of Sciences convened an official panel, which recommended in July 2004 that the HST should be preserved despite the apparent risks. Their report urged “NASA should take no actions that would preclude a space shuttle servicing mission to the Hubble Space Telescope”. In August 2004, O’Keefe asked Goddard Space Flight Center to prepare a detailed proposal for a robotic service mission. These plans were later canceled, the robotic mission being described as “not feasible”. In late 2004, several Congressional members, led by Senator Barbara Mikulski, held public hearings and carried on a fight with much public support (including thousands of letters from school children across the U.S.) to get the Bush Administration and NASA to reconsider the decision to drop plans for a Hubble rescue mission.

    The nomination in April 2005 of a new NASA Administrator, Michael D. Griffin, changed the situation, as Griffin stated he would consider a crewed servicing mission. Soon after his appointment Griffin authorized Goddard to proceed with preparations for a crewed Hubble maintenance flight, saying he would make the final decision after the next two shuttle missions. In October 2006 Griffin gave the final go-ahead, and the 11-day mission by Atlantis was scheduled for October 2008. Hubble’s main data-handling unit failed in September 2008, halting all reporting of scientific data until its back-up was brought online on October 25, 2008. Since a failure of the backup unit would leave the HST helpless, the service mission was postponed to incorporate a replacement for the primary unit.

    Servicing Mission 4 (SM4), flown by Atlantis in May 2009, was the last scheduled shuttle mission for HST. SM4 installed the replacement data-handling unit, repaired the ACS and STIS systems, installed improved nickel hydrogen batteries, and replaced other components including all six gyroscopes. SM4 also installed two new observation instruments—Wide Field Camera 3 (WFC3) and the Cosmic Origins Spectrograph (COS)—and the Soft Capture and Rendezvous System, which will enable the future rendezvous, capture, and safe disposal of Hubble by either a crewed or robotic mission. Except for the ACS’s High Resolution Channel, which could not be repaired and was disabled, the work accomplished during SM4 rendered the telescope fully functional.

    Major projects

    Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey [CANDELS]

    The survey “aims to explore galactic evolution in the early Universe, and the very first seeds of cosmic structure at less than one billion years after the Big Bang.” The CANDELS project site describes the survey’s goals as the following:

    The Cosmic Assembly Near-IR Deep Extragalactic Legacy Survey is designed to document the first third of galactic evolution from z = 8 to 1.5 via deep imaging of more than 250,000 galaxies with WFC3/IR and ACS. It will also find the first Type Ia SNe beyond z > 1.5 and establish their accuracy as standard candles for cosmology. Five premier multi-wavelength sky regions are selected; each has multi-wavelength data from Spitzer and other facilities, and has extensive spectroscopy of the brighter galaxies. The use of five widely separated fields mitigates cosmic variance and yields statistically robust and complete samples of galaxies down to 109 solar masses out to z ~ 8.

    Frontier Fields program

    The program, officially named Hubble Deep Fields Initiative 2012, is aimed to advance the knowledge of early galaxy formation by studying high-redshift galaxies in blank fields with the help of gravitational lensing to see the “faintest galaxies in the distant universe”. The Frontier Fields web page describes the goals of the program being:

    To reveal hitherto inaccessible populations of z = 5–10 galaxies that are ten to fifty times fainter intrinsically than any presently known
    To solidify our understanding of the stellar masses and star formation histories of sub-L* galaxies at the earliest times
    To provide the first statistically meaningful morphological characterization of star forming galaxies at z > 5
    To find z > 8 galaxies stretched out enough by cluster lensing to discern internal structure and/or magnified enough by cluster lensing for spectroscopic follow-up.

    Cosmic Evolution Survey (COSMOS)

    The Cosmic Evolution Survey (COSMOS) is an astronomical survey designed to probe the formation and evolution of galaxies as a function of both cosmic time (redshift) and the local galaxy environment. The survey covers a two square degree equatorial field with spectroscopy and X-ray to radio imaging by most of the major space-based telescopes and a number of large ground based telescopes, making it a key focus region of extragalactic astrophysics. COSMOS was launched in 2006 as the largest project pursued by the Hubble Space Telescope at the time, and still is the largest continuous area of sky covered for the purposes of mapping deep space in blank fields, 2.5 times the area of the moon on the sky and 17 times larger than the largest of the CANDELS regions. The COSMOS scientific collaboration that was forged from the initial COSMOS survey is the largest and longest-running extragalactic collaboration, known for its collegiality and openness. The study of galaxies in their environment can be done only with large areas of the sky, larger than a half square degree. More than two million galaxies are detected, spanning 90% of the age of the Universe. The COSMOS collaboration is led by Caitlin Casey, Jeyhan Kartaltepe, and Vernesa Smolcic and involves more than 200 scientists in a dozen countries.

    Important discoveries

    Hubble has helped resolve some long-standing problems in astronomy, while also raising new questions. Some results have required new theories to explain them.

    Age of the universe

    Among its primary mission targets was to measure distances to Cepheid variable stars more accurately than ever before, and thus constrain the value of the Hubble constant, the measure of the rate at which the universe is expanding, which is also related to its age. Before the launch of HST, estimates of the Hubble constant typically had errors of up to 50%, but Hubble measurements of Cepheid variables in the Virgo Cluster and other distant galaxy clusters provided a measured value with an accuracy of ±10%, which is consistent with other more accurate measurements made since Hubble’s launch using other techniques. The estimated age is now about 13.7 billion years, but before the Hubble Telescope, scientists predicted an age ranging from 10 to 20 billion years.

    Expansion of the universe

    While Hubble helped to refine estimates of the age of the universe, it also cast doubt on theories about its future. Astronomers from the High-z Supernova Search Team and the Supernova Cosmology Project used ground-based telescopes and HST to observe distant supernovae and uncovered evidence that, far from decelerating under the influence of gravity, the expansion of the universe may in fact be accelerating. Three members of these two groups have subsequently been awarded Nobel Prizes for their discovery.

    Saul Perlmutter [The Supernova Cosmology Project] shared the 2006 Shaw Prize in Astronomy, the 2011 Nobel Prize in Physics, and the 2015 Breakthrough Prize in Fundamental Physics with Brian P. Schmidt and Adam Riess [The High-z Supernova Search Team] for providing evidence that the expansion of the universe is accelerating.

    The cause of this acceleration remains poorly understood; the most common cause attributed is Dark Energy.

    Black holes

    The high-resolution spectra and images provided by the HST have been especially well-suited to establishing the prevalence of black holes in the center of nearby galaxies. While it had been hypothesized in the early 1960s that black holes would be found at the centers of some galaxies, and astronomers in the 1980s identified a number of good black hole candidates, work conducted with Hubble shows that black holes are probably common to the centers of all galaxies. The Hubble programs further established that the masses of the nuclear black holes and properties of the galaxies are closely related. The legacy of the Hubble programs on black holes in galaxies is thus to demonstrate a deep connection between galaxies and their central black holes.

    Extending visible wavelength images

    A unique window on the Universe enabled by Hubble are the Hubble Deep Field, Hubble Ultra-Deep Field, and Hubble Extreme Deep Field images, which used Hubble’s unmatched sensitivity at visible wavelengths to create images of small patches of sky that are the deepest ever obtained at optical wavelengths. The images reveal galaxies billions of light years away, and have generated a wealth of scientific papers, providing a new window on the early Universe. The Wide Field Camera 3 improved the view of these fields in the infrared and ultraviolet, supporting the discovery of some of the most distant objects yet discovered, such as MACS0647-JD.

    The non-standard object SCP 06F6 was discovered by the Hubble Space Telescope in February 2006.

    On March 3, 2016, researchers using Hubble data announced the discovery of the farthest known galaxy to date: GN-z11. The Hubble observations occurred on February 11, 2015, and April 3, 2015, as part of the CANDELS/GOODS-North surveys.

    Solar System discoveries

    HST has also been used to study objects in the outer reaches of the Solar System, including the dwarf planets Pluto and Eris.

    The collision of Comet Shoemaker-Levy 9 with Jupiter in 1994 was fortuitously timed for astronomers, coming just a few months after Servicing Mission 1 had restored Hubble’s optical performance. Hubble images of the planet were sharper than any taken since the passage of Voyager 2 in 1979, and were crucial in studying the dynamics of the collision of a comet with Jupiter, an event believed to occur once every few centuries.

    During June and July 2012, U.S. astronomers using Hubble discovered Styx, a tiny fifth moon orbiting Pluto.

    In March 2015, researchers announced that measurements of aurorae around Ganymede, one of Jupiter’s moons, revealed that it has a subsurface ocean. Using Hubble to study the motion of its aurorae, the researchers determined that a large saltwater ocean was helping to suppress the interaction between Jupiter’s magnetic field and that of Ganymede. The ocean is estimated to be 100 km (60 mi) deep, trapped beneath a 150 km (90 mi) ice crust.

    From June to August 2015, Hubble was used to search for a Kuiper belt object (KBO) target for the New Horizons Kuiper Belt Extended Mission (KEM) when similar searches with ground telescopes failed to find a suitable target.

    National Aeronautics Space Agency(USA)/New Horizons(US) spacecraft.

    This resulted in the discovery of at least five new KBOs, including the eventual KEM target, 486958 Arrokoth, that New Horizons performed a close fly-by of on January 1, 2019.

    In August 2020, taking advantage of a total lunar eclipse, astronomers using NASA’s Hubble Space Telescope have detected Earth’s own brand of sunscreen – ozone – in our atmosphere. This method simulates how astronomers and astrobiology researchers will search for evidence of life beyond Earth by observing potential “biosignatures” on exoplanets (planets around other stars).
    Hubble and ALMA image of MACS J1149.5+2223.

    Supernova reappearance

    On December 11, 2015, Hubble captured an image of the first-ever predicted reappearance of a supernova, dubbed “Refsdal”, which was calculated using different mass models of a galaxy cluster whose gravity is warping the supernova’s light. The supernova was previously seen in November 2014 behind galaxy cluster MACS J1149.5+2223 as part of Hubble’s Frontier Fields program. Astronomers spotted four separate images of the supernova in an arrangement known as an “Einstein Cross”.

    The light from the cluster has taken about five billion years to reach Earth, though the supernova exploded some 10 billion years ago. Based on early lens models, a fifth image was predicted to reappear by the end of 2015. The detection of Refsdal’s reappearance in December 2015 served as a unique opportunity for astronomers to test their models of how mass, especially dark matter, is distributed within this galaxy cluster.

    Impact on astronomy

    Many objective measures show the positive impact of Hubble data on astronomy. Over 15,000 papers based on Hubble data have been published in peer-reviewed journals, and countless more have appeared in conference proceedings. Looking at papers several years after their publication, about one-third of all astronomy papers have no citations, while only two percent of papers based on Hubble data have no citations. On average, a paper based on Hubble data receives about twice as many citations as papers based on non-Hubble data. Of the 200 papers published each year that receive the most citations, about 10% are based on Hubble data.

    Although the HST has clearly helped astronomical research, its financial cost has been large. A study on the relative astronomical benefits of different sizes of telescopes found that while papers based on HST data generate 15 times as many citations as a 4 m (13 ft) ground-based telescope such as the William Herschel Telescope, the HST costs about 100 times as much to build and maintain.

    Isaac Newton Group 4.2 meter William Herschel Telescope at Roque de los Muchachos Observatory | Instituto de Astrofísica de Canarias • IAC(ES) on La Palma in the Canary Islands(ES), 2,396 m (7,861 ft)

    Deciding between building ground- versus space-based telescopes is complex. Even before Hubble was launched, specialized ground-based techniques such as aperture masking interferometry had obtained higher-resolution optical and infrared images than Hubble would achieve, though restricted to targets about 108 times brighter than the faintest targets observed by Hubble. Since then, advances in “adaptive optics” have extended the high-resolution imaging capabilities of ground-based telescopes to the infrared imaging of faint objects.

    Glistening against the awesome backdrop of the night sky above ESO’s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT, a major asset of the Adaptive Optics system.

    UCO KeckLaser Guide Star Adaptive Optics on two 10 meter Keck Observatory telescopes, Maunakea Hawaii USA, altitude 4,207 m (13,802 ft).

    The usefulness of adaptive optics versus HST observations depends strongly on the particular details of the research questions being asked. In the visible bands, adaptive optics can correct only a relatively small field of view, whereas HST can conduct high-resolution optical imaging over a wide field. Only a small fraction of astronomical objects are accessible to high-resolution ground-based imaging; in contrast Hubble can perform high-resolution observations of any part of the night sky, and on objects that are extremely faint.

    Impact on aerospace engineering

    In addition to its scientific results, Hubble has also made significant contributions to aerospace engineering, in particular the performance of systems in low Earth orbit. These insights result from Hubble’s long lifetime on orbit, extensive instrumentation, and return of assemblies to the Earth where they can be studied in detail. In particular, Hubble has contributed to studies of the behavior of graphite composite structures in vacuum, optical contamination from residual gas and human servicing, radiation damage to electronics and sensors, and the long term behavior of multi-layer insulation. One lesson learned was that gyroscopes assembled using pressurized oxygen to deliver suspension fluid were prone to failure due to electric wire corrosion. Gyroscopes are now assembled using pressurized nitrogen. Another is that optical surfaces in LEO can have surprisingly long lifetimes; Hubble was only expected to last 15 years before the mirror became unusable, but after 14 years there was no measureable degradation. Finally, Hubble servicing missions, particularly those that serviced components not designed for in-space maintenance, have contributed towards the development of new tools and techniques for on-orbit repair.

    Archives

    All Hubble data is eventually made available via the Mikulski Archive for Space Telescopes at STScI, CADC and ESA/ESAC. Data is usually proprietary—available only to the principal investigator (PI) and astronomers designated by the PI—for twelve months after being taken. The PI can apply to the director of the STScI to extend or reduce the proprietary period in some circumstances.

    Observations made on Director’s Discretionary Time are exempt from the proprietary period, and are released to the public immediately. Calibration data such as flat fields and dark frames are also publicly available straight away. All data in the archive is in the FITS format, which is suitable for astronomical analysis but not for public use. The Hubble Heritage Project processes and releases to the public a small selection of the most striking images in JPEG and TIFF formats.

    Outreach activities

    It has always been important for the Space Telescope to capture the public’s imagination, given the considerable contribution of taxpayers to its construction and operational costs. After the difficult early years when the faulty mirror severely dented Hubble’s reputation with the public, the first servicing mission allowed its rehabilitation as the corrected optics produced numerous remarkable images.

    Several initiatives have helped to keep the public informed about Hubble activities. In the United States, outreach efforts are coordinated by the Space Telescope Science Institute (STScI) Office for Public Outreach, which was established in 2000 to ensure that U.S. taxpayers saw the benefits of their investment in the space telescope program. To that end, STScI operates the HubbleSite.org website. The Hubble Heritage Project, operating out of the STScI, provides the public with high-quality images of the most interesting and striking objects observed. The Heritage team is composed of amateur and professional astronomers, as well as people with backgrounds outside astronomy, and emphasizes the aesthetic nature of Hubble images. The Heritage Project is granted a small amount of time to observe objects which, for scientific reasons, may not have images taken at enough wavelengths to construct a full-color image.

    Since 1999, the leading Hubble outreach group in Europe has been the Hubble European Space Agency Information Centre (HEIC). This office was established at the Space Telescope European Coordinating Facility in Munich, Germany. HEIC’s mission is to fulfill HST outreach and education tasks for the European Space Agency. The work is centered on the production of news and photo releases that highlight interesting Hubble results and images. These are often European in origin, and so increase awareness of both ESA’s Hubble share (15%) and the contribution of European scientists to the observatory. ESA produces educational material, including a videocast series called Hubblecast designed to share world-class scientific news with the public.

    The Hubble Space Telescope has won two Space Achievement Awards from the Space Foundation, for its outreach activities, in 2001 and 2010.

    A replica of the Hubble Space Telescope is on the courthouse lawn in Marshfield, Missouri, the hometown of namesake Edwin P. Hubble.

    Major Instrumentation

    Hubble WFPC2 no longer in service.

    Wide Field Camera 3 [WFC3]

    National Aeronautics Space Agency(USA)/European Space Agency [Agence spatiale européenne](EU) Hubble Wide Field Camera 3

    Advanced Camera for Surveys [ACS]

    National Aeronautics Space Agency(US)/European Space Agency [Agence spatiale européenne][Europäische Weltraumorganisation](EU) NASA/ESA Hubble Space Telescope(US) Advanced Camera for Surveys

    Cosmic Origins Spectrograph [COS]

    National Aeronautics Space Agency (US) Cosmic Origins Spectrograph.

    The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA’s Goddard Space Flight Center manages the telescope. The Space Telescope Science Institute (STScI), is a free-standing science center, located on the campus of The Johns Hopkins University and operated by the Association of Universities for Research in Astronomy (AURA) for NASA, conducts Hubble science operations.

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  • richardmitnick 11:35 am on November 19, 2021 Permalink | Reply
    Tags: "Astronomers May Have Detected a Rare 'Missing Link' Black Hole in Our Closest Neighbor", A globular cluster of stars within Andromeda called B023-G078., , , , , Science Alert (US)   

    From Science Alert (US) : “Astronomers May Have Detected a Rare ‘Missing Link’ Black Hole in Our Closest Neighbor” 

    ScienceAlert

    From Science Alert (US)

    19 NOVEMBER 2021
    MICHELLE STARR

    Andromeda Galaxy Messier 31. Credit: Adam Evans.

    A rare treasure that could shed light on the evolution of black holes has just been found in the Milky Way’s closest large galactic neighbor.

    In a cluster of stars in the Andromeda galaxy, AKA Messier 31, astronomers have studied changes in light to identify a black hole clocking in at almost 100,000 times the mass of the Sun. That places the beast squarely in the regime of “intermediate mass” – both elusive and highly sought by astronomers for the questions they can answer.

    “In this paper,” wrote an international team of astronomers led by Renuka Pechetti of Liverpool John Moores University (UK), “we use high-resolution mass models and kinematics to present the detection of a ~100,000 solar-mass intermediate-mass black hole (IMBH) with greater than 3-sigma significance.”

    2
    Globular cluster B023-G78 in the Andromeda Galaxy. (Pechetti et al., arXiv, 2021)

    Their work has been accepted for publication by the American Astronomical Society (AAS).

    Black holes are very tricksome beasts. Unless they’re actively accreting matter, a process that generates incredibly bright radiation, they give off no light we can detect. This makes finding them a matter of detective work, looking at what’s happening in their surrounding space.

    One such clue to the presence of a black hole is the orbits of objects around them.

    Most of the black holes we’ve detected, using a variety of methods, fall into two mass ranges. There are the stellar-mass black holes, up to around 100 times the mass of the Sun; and supermassive black holes, which start at a low range of around a million times the mass of the Sun (and can get unbelievably chonky from there).

    In the middle is a range classified as intermediate, and to say that detections of these black holes are rare is an understatement.

    To date, the number of IMBH detections remains incredibly low. This is something of a vexation; without intermediate-mass black holes, scientists struggle to resolve how two wildly different mass regimes can coexist.

    A solid population of black holes in the intermediate mass range could help us bridge the gap, proffering a mechanism whereby stellar-mass black holes can grow into behemoths.

    This brings us to Andromeda; specifically, a globular cluster of stars within Andromeda called B023-G078.

    B023-G078 is the most massive such star cluster in the galaxy, a roughly spherical, gravitationally bound cluster of stars clocking in at 6.2 million solar masses.

    One way that these clusters can form, according to models, is when one galaxy subsumes another. This is a very common phenomenon; the Milky Way has done it several times, as has Andromeda. Globular clusters might be what’s left of the galactic cores of smaller galaxies that get subsumed by larger ones, black holes and all.

    This is what Pechetti and her colleagues think is B023-G078’s origin story. They studied the metal content of the cluster, based on subtle signatures in the light it emits, and determined that it has an age of about 10.5 billion years, with a metallicity similar to those of other stripped galactic cores in the Milky Way.

    Then, they studied the way the stars move around the center of the cluster to try to calculate the mass of the black hole that ought to be therein. This returned a result of around 91,000 solar masses, which constitutes around 1.5 percent of the mass of the cluster.

    This suggests that B023-G078’s parent galaxy was a dwarf galaxy, clocking in at around a billion solar masses. The mass of the Large Magellanic Cloud – a dwarf galaxy orbiting the Milky Way – has been calculated at 188 billion solar masses, and Andromeda is estimated to be up to around 1.5 trillion solar masses.

    lmc Large Magellanic Cloud. ESO’s VISTA telescope reveals a remarkable image of the Large Magellanic Cloud.

    It’s possible that something else accounts for the observations, but none of the alternatives explored by the team fit the data as well as an intermediate-mass black hole.

    “We favor the presence of a single IMBH given the other indications that B023-G78 is a stripped nucleus, as well as the apparent compactness of the dark component,” they wrote in their paper.

    “Higher spatial-resolution data would give improved constraints on the nature of the central dark mass and should be a high priority in the forthcoming era of extremely large telescopes.”

    See the full article here .

    See also this related blog post.


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    Please help promote STEM in your local schools.


    Stem Education Coalition

     
  • richardmitnick 10:54 am on November 16, 2021 Permalink | Reply
    Tags: "Mysterious Object Glimpsed Decades Ago Might Have Actually Been Planet Nine", , , , , Science Alert (US),   

    From University College London (UK) via Science Alert (US) : “Mysterious Object Glimpsed Decades Ago Might Have Actually Been Planet Nine” 

    UCL bloc

    From University College London (UK)

    via

    ScienceAlert

    Science Alert (US)

    16 NOVEMBER 2021
    MICHELLE STARR

    1
    Artistic rendering of Planet Nine. Credit: Tomruen/Wikimedia Commons, CC BY-SA 3.0.

    It’s one of the most intriguing questions about the Solar System from the last five years: Is there a large planet, lurking out in the cold dark reaches, on an orbit so wide it could take 20,000 years to complete?

    The answer has proven elusive, but a new study reveals what could be traces of the mysterious hypothetical object’s existence.

    Astronomer Michael Rowan-Robinson of The University College London (UK) conducted an analysis of data collected by the Infrared Astronomical Satellite (IRAS) in 1983, and found a trio of point sources that just might be Planet Nine.

    NASA/UK/NL Infrared Astronomical Survey IRAS spacecraft

    2
    Six distant objects in the Solar System with orbits exclusively beyond Neptune (magenta) all line up in a single direction, and tilt nearly identically away from the plane of the Solar System. The orange ellipse indicates the hypothetical Planet Nine orbit required to maintain this configuration. Credit: R. Hurt/Caltech IPAC-Infrared Processing and Analysis Center (US).

    This, Rowan-Robinson concludes in MNRAS, is actually fairly unlikely to be a real detection, but the possibility does mean that it could be used to model where the planet might be now in order to conduct a more targeted search, in the quest to confirm or rule out its existence.

    “Given the poor quality of the IRAS detections, at the very limit of the survey, and in a very difficult part of the sky for far infrared detections, the probability of the candidate being real is not overwhelming,” he wrote.

    “However, given the great interest of the Planet 9 hypothesis, it would be worthwhile to check whether an object with the proposed parameters and in the region of sky proposed, is inconsistent with the planetary ephemerides.”

    Speculation about the existence of a hidden planet in the outer reaches of the Solar System has swirled for decades, but it reached a new pitch in 2016 with the publication of a paper proposing new evidence [The Astronomical Journal].

    Astronomers Mike Brown and Konstantin Batygin of The California Institute of Technology (US) found that small objects in the outer Solar System’s Kuiper Belt were orbiting oddly, as though pushed into a pattern under the gravitational influence of something large.

    But finding the dratted thing is a lot more complicated than it might sound. If it is out there, it could be five to 10 times the mass of Earth, orbiting at a distance somewhere between 400 and 800 astronomical units (an astronomical unit is the average distance between Earth and the Sun; Pluto, for context, is around 40 astronomical units from the Sun).

    This object is very far away, and quite small and cold and probably not reflecting much sunlight at all; and, moreover, we don’t know exactly where in the very large sky it is. So the jury is out on whether it is real or not, and the topic is one of pretty intense and interesting debate.

    IRAS operated for 10 months from January 1983, taking a far-infrared survey of 96 percent of the sky. In this wavelength, small, cool objects like Planet Nine might be detectable, so Rowan-Robinson decided to re-analyze the data using parameters consistent with Planet Nine.

    Of the around 250,000 point sources detected by the satellite, just three are of interest as a candidate for Planet Nine. In June, July, and September of 1983, the satellite picked out what appears to be an object moving across the sky.

    It’s not a dead cert, by a long shot. The region of sky in which the source appears is at low galactic latitude (that is, close to the plane of the galaxy), and strongly affected by galactic cirrus, filamentary clouds that glow in far-infrared. So it’s possible that the sources are noise from these clouds.

    Rowan-Robinson also notes that another highly sensitive survey, Panoramic Survey Telescope and Rapid Response System (Pan-STARRS), in operation since 2008, has failed to recover the candidate.

    U Hawaii Pan-STARRS1 (PS1) Panoramic Survey Telescope and Rapid Response System is a 1.8-meter diameter telescope situated at Haleakala Observatories near the summit of Haleakala, altitude 10,023 ft (3,055 m) on the Island of Maui, Hawaii, USA. It is equipped with the world’s largest digital camera, with almost 1.4 billion pixels.

    However, if we interpret the candidate as real, we can extrapolate some information about Planet Nine. According to the IRAS data, it would be between three and five times the mass of Earth, at an orbital distance of around 225 astronomical units.

    The motion of the source across the sky also gives us an idea of the potential planet’s orbit, telling us where in the sky we could be looking now, and where we can look in other data, such as that from Pan-STARRS.

    “Dynamical studies are needed to check whether such an object is consistent with the ephemerides of other Solar System objects and whether this object can account for the clustering of the orbits of Kuiper belt dwarf planets,” Rowan-Robinson writes.

    Kuiper Belt. Minor Planet Center.

    “The IRAS detections are not of the highest quality but it would be worth searching at optical and near infrared wavelengths in an annulus of radius 2.5-4 deg centered on the 1983 position. This candidate could be ruled out if radio or other observations confirmed the reality (and stationarity) of the IRAS sources at the 1983 … positions.”

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    UCL campus

    Established in 1826, as London University by founders inspired by the radical ideas of Jeremy Bentham, University College London (UK) was the first university institution to be established in London, and the first in England to be entirely secular and to admit students regardless of their religion. University College London (UK) also makes contested claims to being the third-oldest university in England and the first to admit women. In 1836, University College London (UK) became one of the two founding colleges of the University of London (UK), which was granted a royal charter in the same year. It has grown through mergers, including with the Institute of Ophthalmology (in 1995); the Institute of Neurology (in 1997); the Royal Free Hospital Medical School (in 1998); the Eastman Dental Institute (in 1999); the School of Slavonic and East European Studies (in 1999); the School of Pharmacy (in 2012) and the Institute of Education (in 2014).

    University College London (UK) has its main campus in the Bloomsbury area of central London, with a number of institutes and teaching hospitals elsewhere in central London and satellite campuses in Queen Elizabeth Olympic Park in Stratford, east London and in Doha, Qatar. University College London (UK) is organised into 11 constituent faculties, within which there are over 100 departments, institutes and research centres. University College London (UK) operates several museums and collections in a wide range of fields, including the Petrie Museum of Egyptian Archaeology and the Grant Museum of Zoology and Comparative Anatomy, and administers the annual Orwell Prize in political writing. In 2019/20, UCL had around 43,840 students and 16,400 staff (including around 7,100 academic staff and 840 professors) and had a total income of £1.54 billion, of which £468 million was from research grants and contracts.

    University College London (UK) is a member of numerous academic organisations, including the Russell Group(UK) and the League of European Research Universities, and is part of UCL Partners, the world’s largest academic health science centre, and is considered part of the “golden triangle” of elite, research-intensive universities in England.

    University College London (UK) has many notable alumni, including the respective “Fathers of the Nation” of India; Kenya and Mauritius; the founders of Ghana; modern Japan; Nigeria; the inventor of the telephone; and one of the co-discoverers of the structure of DNA. UCL academics discovered five of the naturally occurring noble gases; discovered hormones; invented the vacuum tube; and made several foundational advances in modern statistics. As of 2020, 34 Nobel Prize winners and 3 Fields medalists have been affiliated with UCL as alumni, faculty or researchers.

    History

    University College London (UK) was founded on 11 February 1826 under the name London University, as an alternative to the Anglican universities of the University of Oxford(UK) and University of Cambridge(UK). London University’s first Warden was Leonard Horner, who was the first scientist to head a British university.

    Despite the commonly held belief that the philosopher Jeremy Bentham was the founder of University College London (UK), his direct involvement was limited to the purchase of share No. 633, at a cost of £100 paid in nine installments between December 1826 and January 1830. In 1828 he did nominate a friend to sit on the council, and in 1827 attempted to have his disciple John Bowring appointed as the first professor of English or History, but on both occasions his candidates were unsuccessful. This suggests that while his ideas may have been influential, he himself was less so. However, Bentham is today commonly regarded as the “spiritual father” of University College London (UK), as his radical ideas on education and society were the inspiration to the institution’s founders, particularly the Scotsmen James Mill (1773–1836) and Henry Brougham (1778–1868).

    In 1827, the Chair of Political Economy at London University was created, with John Ramsay McCulloch as the first incumbent, establishing one of the first departments of economics in England. In 1828 the university became the first in England to offer English as a subject and the teaching of Classics and medicine began. In 1830, London University founded the London University School, which would later become University College School. In 1833, the university appointed Alexander Maconochie, Secretary to the Royal Geographical Society, as the first professor of geography in the British Isles. In 1834, University College Hospital (originally North London Hospital) opened as a teaching hospital for the university’s medical school.

    1836 to 1900 – University College, London

    In 1836, London University was incorporated by royal charter under the name University College, London. On the same day, the University of London was created by royal charter as a degree-awarding examining board for students from affiliated schools and colleges, with University College and King’s College, London being named in the charter as the first two affiliates.

    The Slade School of Fine Art was founded as part of University College in 1871, following a bequest from Felix Slade.

    In 1878, the University College London (UK) gained a supplemental charter making it the first British university to be allowed to award degrees to women. The same year University College London (UK) admitted women to the faculties of Arts and Law and of Science, although women remained barred from the faculties of Engineering and of Medicine (with the exception of courses on public health and hygiene). While University College London (UK) claims to have been the first university in England to admit women on equal terms to men, from 1878, the University of Bristol(UK) also makes this claim, having admitted women from its foundation (as a college) in 1876. Armstrong College, a predecessor institution of Newcastle University (UK), also allowed women to enter from its foundation in 1871, although none actually enrolled until 1881. Women were finally admitted to medical studies during the First World War in 1917, although limitations were placed on their numbers after the war ended.

    In 1898, Sir William Ramsay discovered the elements krypton; neon; and xenon whilst professor of chemistry at University College London (UK).

    1900 to 1976 – University of London, University College

    In 1900, the University College London (UK) was reconstituted as a federal university with new statutes drawn up under the University of London Act 1898. UCL, along with a number of other colleges in London, became a school of the University of London. While most of the constituent institutions retained their autonomy, University College London (UK) was merged into the University in 1907 under the University College London (Transfer) Act 1905 and lost its legal independence. Its formal name became University College London (UK), University College, although for most informal and external purposes the name “University College, London” (or the initialism UCL) was still used.

    1900 also saw the decision to appoint a salaried head of the college. The first incumbent was Carey Foster, who served as Principal (as the post was originally titled) from 1900 to 1904. He was succeeded by Gregory Foster (no relation), and in 1906 the title was changed to Provost to avoid confusion with the Principal of the University of London. Gregory Foster remained in post until 1929. In 1906, the Cruciform Building was opened as the new home for University College Hospital.

    As it acknowledged and apologized for in 2021, University College London (UK) played “a fundamental role in the development, propagation and legitimisation of eugenics” during the first half of the 20th century. Among the prominent eugenicists who taught at University College London (UK) were Francis Galton, who coined the term “eugenics”, and Karl Pearson, and eugenics conferences were held at UCL until 2017.

    University College London (UK) sustained considerable bomb damage during the Second World War, including the complete destruction of the Great Hall and the Carey Foster Physics Laboratory. Fires gutted the library and destroyed much of the main building, including the dome. The departments were dispersed across the country to Aberystwyth; Bangor; Gwynedd; University of Cambridge (UK) ; University of Oxford (UK); Rothamsted near Harpenden; Hertfordshire; and Sheffield, with the administration at Stanstead Bury near Ware, Hertfordshire. The first UCL student magazine, Pi, was published for the first time on 21 February 1946. The Institute of Jewish Studies relocated to UCL in 1959.

    The Mullard Space Science Laboratory(UK) was established in 1967. In 1973, UCL became the first international node to the precursor of the internet, the ARPANET.

    Although University College London (UK) was among the first universities to admit women on the same terms as men, in 1878, the college’s senior common room, the Housman Room, remained men-only until 1969. After two unsuccessful attempts, a motion was passed that ended segregation by sex at University College London (UK). This was achieved by Brian Woledge (Fielden Professor of French at University College London (UK) from 1939 to 1971) and David Colquhoun, at that time a young lecturer in pharmacology.

    1976 to 2005 – University College London (UK)

    In 1976, a new charter restored University College London (UK) ‘s legal independence, although still without the power to award its own degrees. Under this charter the college became formally known as University College London (UK). This name abandoned the comma used in its earlier name of “University College, London”.

    In 1986, University College London (UK) merged with the Institute of Archaeology. In 1988, University College London (UK) merged with the Institute of Laryngology & Otology; the Institute of Orthopaedics; the Institute of Urology & Nephrology; and Middlesex Hospital Medical School.

    In 1993, a reorganisation of the University of London (UK) meant that University College London (UK) and other colleges gained direct access to government funding and the right to confer University of London degrees themselves. This led to University College London (UK) being regarded as a de facto university in its own right.

    In 1994, the University College London (UK) Hospitals NHS Trust was established. University College London (UK) merged with the College of Speech Sciences and the Institute of Ophthalmology in 1995; the Institute of Child Health and the School of Podiatry in 1996; and the Institute of Neurology in 1997. In 1998, UCL merged with the Royal Free Hospital Medical School to create the Royal Free and University College Medical School (renamed the University College London (UK) Medical School in October 2008). In 1999, UCL merged with the School of Slavonic and East European Studies and the Eastman Dental Institute.

    The University College London (UK) Jill Dando Institute of Crime Science, the first university department in the world devoted specifically to reducing crime, was founded in 2001.

    Proposals for a merger between University College London (UK) and Imperial College London(UK) were announced in 2002. The proposal provoked strong opposition from University College London (UK) teaching staff and students and the AUT union, which criticised “the indecent haste and lack of consultation”, leading to its abandonment by University College London (UK) provost Sir Derek Roberts. The blogs that helped to stop the merger are preserved, though some of the links are now broken: see David Colquhoun’s blog and the Save University College London (UK) blog, which was run by David Conway, a postgraduate student in the department of Hebrew and Jewish studies.

    The London Centre for Nanotechnology was established in 2003 as a joint venture between University College London (UK) and Imperial College London (UK). They were later joined by King’s College London(UK) in 2018.

    Since 2003, when University College London (UK) professor David Latchman became master of the neighbouring Birkbeck, he has forged closer relations between these two University of London colleges, and personally maintains departments at both. Joint research centres include the UCL/Birkbeck Institute for Earth and Planetary Sciences; the University College London (UK) /Birkbeck/IoE Centre for Educational Neuroscience; the University College London (UK) /Birkbeck Institute of Structural and Molecular Biology; and the Birkbeck- University College London (UK) Centre for Neuroimaging.

    2005 to 2010

    In 2005, University College London (UK) was finally granted its own taught and research degree awarding powers and all University College London (UK) students registered from 2007/08 qualified with University College London (UK) degrees. Also in 2005, University College London (UK) adopted a new corporate branding under which the name University College London (UK) was replaced by the initialism UCL in all external communications. In the same year, a major new £422 million building was opened for University College Hospital on Euston Road, the University College London (UK) Ear Institute was established and a new building for the University College London (UK) School of Slavonic and East European Studies was opened.

    In 2007, the University College London (UK) Cancer Institute was opened in the newly constructed Paul O’Gorman Building. In August 2008, University College London (UK) formed UCL Partners, an academic health science centre, with Great Ormond Street Hospital for Children NHS Trust; Moorfields Eye Hospital NHS Foundation Trust; Royal Free London NHS Foundation Trust; and University College London Hospitals NHS Foundation Trust. In 2008, University College London (UK) established the University College London (UK) School of Energy & Resources in Adelaide, Australia, the first campus of a British university in the country. The School was based in the historic Torrens Building in Victoria Square and its creation followed negotiations between University College London (UK) Vice Provost Michael Worton and South Australian Premier Mike Rann.

    In 2009, the Yale UCL Collaborative was established between University College London (UK); UCL Partners; Yale University(US); Yale School of Medicine; and Yale – New Haven Hospital. It is the largest collaboration in the history of either university, and its scope has subsequently been extended to the humanities and social sciences.

    2010 to 2015

    In June 2011, the mining company BHP Billiton agreed to donate AU$10 million to University College London (UK) to fund the establishment of two energy institutes – the Energy Policy Institute; based in Adelaide, and the Institute for Sustainable Resources, based in London.

    In November 2011, University College London (UK) announced plans for a £500 million investment in its main Bloomsbury campus over 10 years, as well as the establishment of a new 23-acre campus next to the Olympic Park in Stratford in the East End of London. It revised its plans of expansion in East London and in December 2014 announced to build a campus (UCL East) covering 11 acres and provide up to 125,000m^2 of space on Queen Elizabeth Olympic Park. UCL East will be part of plans to transform the Olympic Park into a cultural and innovation hub, where University College London (UK) will open its first school of design, a centre of experimental engineering and a museum of the future, along with a living space for students.

    The School of Pharmacy, University of London merged with University College London (UK) on 1 January 2012, becoming the University College London (UK) School of Pharmacy within the Faculty of Life Sciences. In May 2012, University College London (UK), Imperial College London and the semiconductor company Intel announced the establishment of the Intel Collaborative Research Institute for Sustainable Connected Cities, a London-based institute for research into the future of cities.

    In August 2012, University College London (UK) received criticism for advertising an unpaid research position; it subsequently withdrew the advert.

    University College London (UK) and the Institute of Education formed a strategic alliance in October 2012, including co-operation in teaching, research and the development of the London schools system. In February 2014, the two institutions announced their intention to merge, and the merger was completed in December 2014.

    In September 2013, a new Department of Science, Technology, Engineering and Public Policy (STEaPP) was established within the Faculty of Engineering, one of several initiatives within the university to increase and reflect upon the links between research and public sector decision-making.

    In October 2013, it was announced that the Translation Studies Unit of Imperial College London would move to University College London (UK), becoming part of the University College London (UK) School of European Languages, Culture and Society. In December 2013, it was announced that University College London (UK) and the academic publishing company Elsevier would collaborate to establish the UCL Big Data Institute. In January 2015, it was announced that University College London (UK) had been selected by the UK government as one of the five founding members of the Alan Turing Institute(UK) (together with the universities of Cambridge, University of Edinburgh(SCL), Oxford and University of Warwick(UK)), an institute to be established at the British Library to promote the development and use of advanced mathematics, computer science, algorithms and big data.

    2015 to 2020

    In August 2015, the Department of Management Science and Innovation was renamed as the School of Management and plans were announced to greatly expand University College London (UK) ‘s activities in the area of business-related teaching and research. The school moved from the Bloomsbury campus to One Canada Square in Canary Wharf in 2016.

    University College London (UK) established the Institute of Advanced Studies (IAS) in 2015 to promote interdisciplinary research in humanities and social sciences. The prestigious annual Orwell Prize for political writing moved to the IAS in 2016.

    In June 2016 it was reported in Times Higher Education that as a result of administrative errors hundreds of students who studied at the UCL Eastman Dental Institute between 2005–06 and 2013–14 had been given the wrong marks, leading to an unknown number of students being attributed with the wrong qualifications and, in some cases, being failed when they should have passed their degrees. A report by University College London (UK) ‘s Academic Committee Review Panel noted that, according to the institute’s own review findings, senior members of University College London (UK) staff had been aware of issues affecting students’ results but had not taken action to address them. The Review Panel concluded that there had been an apparent lack of ownership of these matters amongst the institute’s senior staff.

    In December 2016 it was announced that University College London (UK) would be the hub institution for a new £250 million national dementia research institute, to be funded with £150 million from the Medical Research Council and £50 million each from Alzheimer’s Research UK and the Alzheimer’s Society.

    In May 2017 it was reported that staff morale was at “an all time low”, with 68% of members of the academic board who responded to a survey disagreeing with the statement ” University College London (UK) is well managed” and 86% with “the teaching facilities are adequate for the number of students”. Michael Arthur, the Provost and President, linked the results to the “major change programme” at University College London (UK). He admitted that facilities were under pressure following growth over the past decade, but said that the issues were being addressed through the development of UCL East and rental of other additional space.

    In October 2017 University College London (UK) ‘s council voted to apply for university status while remaining part of the University of London. University College London (UK) ‘s application to become a university was subject to Parliament passing a bill to amend the statutes of the University of London, which received royal assent on 20 December 2018.

    The University College London (UK) Adelaide satellite campus closed in December 2017, with academic staff and student transferring to the University of South Australia(AU). As of 2019 UniSA and University College London (UK) are offering a joint masters qualification in Science in Data Science (international).

    In 2018, University College London (UK) opened UCL at Here East, at the Queen Elizabeth Olympic Park, offering courses jointly between the Bartlett Faculty of the Built Environment and the Faculty of Engineering Sciences. The campus offers a variety of undergraduate and postgraduate master’s degrees, with the first undergraduate students, on a new Engineering and Architectural Design MEng, starting in September 2018. It was announced in August 2018 that a £215 million contract for construction of the largest building in the UCL East development, Marshgate 1, had been awarded to Mace, with building to begin in 2019 and be completed by 2022.

    In 2017 University College London (UK) disciplined an IT administrator who was also the University and College Union (UCU) branch secretary for refusing to take down an unmoderated staff mailing list. An employment tribunal subsequently ruled that he was engaged in union activities and thus this disciplinary action was unlawful. As of June 2019 University College London (UK) is appealing this ruling and the UCU congress has declared this to be a “dispute of national significance”.

    2020 to present

    In 2021 University College London (UK) formed a strategic partnership with Facebook AI Research (FAIR), including the creation of a new PhD programme.

    Research

    University College London (UK) has made cross-disciplinary research a priority and orientates its research around four “Grand Challenges”, Global Health, Sustainable Cities, Intercultural Interaction and Human Wellbeing.

    In 2014/15, University College London (UK) had a total research income of £427.5 million, the third-highest of any British university (after the University of Oxford and Imperial College London). Key sources of research income in that year were BIS research councils (£148.3 million); UK-based charities (£106.5 million); UK central government; local/health authorities and hospitals (£61.5 million); EU government bodies (£45.5 million); and UK industry, commerce and public corporations (£16.2 million). In 2015/16, University College London (UK) was awarded a total of £85.8 million in grants by UK research councils, the second-largest amount of any British university (after the University of Oxford), having achieved a 28% success rate. For the period to June 2015, University College London (UK) was the fifth-largest recipient of Horizon 2020 EU research funding and the largest recipient of any university, with €49.93 million of grants received. University College London (UK) also had the fifth-largest number of projects funded of any organisation, with 94.

    According to a ranking of universities produced by SCImago Research Group University College London (UK) is ranked 12th in the world (and 1st in Europe) in terms of total research output. According to data released in July 2008 by ISI Web of Knowledge, University College London (UK) is the 13th most-cited university in the world (and most-cited in Europe). The analysis covered citations from 1 January 1998 to 30 April 2008, during which 46,166 UCL research papers attracted 803,566 citations. The report covered citations in 21 subject areas and the results revealed some of University College London (UK) ‘s key strengths, including: Clinical Medicine (1st outside North America); Immunology (2nd in Europe); Neuroscience & Behaviour (1st outside North America and 2nd in the world); Pharmacology & Toxicology (1st outside North America and 4th in the world); Psychiatry & Psychology (2nd outside North America); and Social Sciences, General (1st outside North America).

    University College London (UK) submitted a total of 2,566 staff across 36 units of assessment to the 2014 Research Excellence Framework (REF) assessment, in each case the highest number of any UK university (compared with 1,793 UCL staff submitted to the 2008 Research Assessment Exercise (RAE 2008)). In the REF results 43% of University College London (UK) ‘s submitted research was classified as 4* (world-leading); 39% as 3* (internationally excellent); 15% as 2* (recognised internationally) and 2% as 1* (recognised nationally), giving an overall GPA of 3.22 (RAE 2008: 4* – 27%, 3* – 39%, 2* – 27% and 1* – 6%). In rankings produced by Times Higher Education based upon the REF results, University College London (UK) was ranked 1st overall for “research power” and joint 8th for GPA (compared to 4th and 7th respectively in equivalent rankings for the RAE 2008).

     
  • richardmitnick 11:12 am on November 15, 2021 Permalink | Reply
    Tags: "This Volcano Erupted For 5 Years Straight and The Photos Are Out of This World", Science Alert (US), The Hawaiian Volcano Observatory, ,   

    From The United States Geological Survey (US) via Science Alert (US) : “This Volcano Erupted For 5 Years Straight and The Photos Are Out of This World” 

    From The United States Geological Survey (US)

    2
    The Hawaiian Volcano Observatory (HVO) is a volcano observatory located at Uwekahuna Bluff on the rim of Kīlauea Caldera on the Island of Hawaiʻi. The observatory monitors four active Hawaiian volcanoes: Kīlauea, Mauna Loa, Hualālai, and Haleakalā. Because Kīlauea and Mauna Loa are significantly more active than Hualālai and Haleakalā, much of the observatory’s research is concentrated on the former two mountains. The observatory has a worldwide reputation as a leader in the study of active volcanism. Due to the relatively non-explosive nature of Hawaiian volcanic eruptions, scientists can study on-going eruptions in proximity without being in extreme danger. Located at the main site is the public Thomas A. Jaggar Museum.

    via

    ScienceAlert

    Science Alert (US)

    15 NOVEMBER 2021
    SIGNE DEAN

    1
    Kilauea lava dome. Credit: USGS.

    On 24 May 1969, a deep rumbling started within Kīlauea, the largest of the volcanoes comprising the island of Hawai’i.

    Those were the first moments of the historical Maunaulu eruption – a spectacular outpouring of lava that lasted for a total of 1,774 days, at the time becoming the longest Kīlauea eruption in at least two millennia.

    Staff at the Hawaiian Volcano Observatory had noted that the magma reservoir underneath the tip of the volcano had started to swell, but they still didn’t expect the magnificent activity that lasted well into the summer of 1974.

    So huge was this eruption that the cooling lava created a whole new landscape on the side of Kīlauea, earning the name of “growing mountain”, or Maunaulu.

    In 1969 alone, twelve huge lava fountains erupted at the site, and much of this activity has been captured for posterity in glorious photographs.

    In 2018, the United States Geological Survey (USGS) reminded the world of the Maunaulu eruption with a throwback photo to one of the rarest types of a lava fountain you can possibly get [above].

    Usually, lava just explodes all over the place without any rhyme or reason, making this beautiful, perfectly rounded dome fountain all the more special. (By the way, the foreground is not the ocean, as it might seem at first glance – it’s a landscape of cooled lava.)

    Lava fountains, in all their blazing glory of raw exploding geology, can reach the dizzying heights of 500 meters, according to USGS.

    They typically happen when lava shoots out of an isolated vent or a fissure in the volcano, or when water in a confined space gets inside a lava tube.

    And, if you like this photo, Maunaulu certainly produced more incredible scenery.

    On June 25 of the same year, a massive 220-meter (722-foot) fountain of lava shot up from the volcano:

    3

    On August 15 of 1969, there was this little splatter of boiling hot rock, just 8 meters (26 feet) high but shaped rather like a searing mushroom cloud. At that point in the eruption, activity like this was almost constantly happening at Maunaulu:

    4

    One of the most spectacular events during the eruption were these 100-meter high ‘lava falls’ overflowing the ‘Alae Crater on Kīlauea, on 5 August 1969.

    “For the two seasoned observers who witnessed this awe-inspiring event, nothing else matched it during the entire Maunaulu eruption,” USGS writes on their website.

    5

    Even after that stunning event, Kīlauea was far from done inspiring awe in its observers. Another massive lava fountain shot up in the air on October 20, and in this photo you can even see a geologist standing on a viewing platform about 800 meters (2,625 feet) away.

    Despite the considerable distance, observers still had to hide behind a stone wall as the heat was so intense – sometimes dry grass right next to the platform would even catch fire.

    Of course, Kīlauea hardly rests. Just nine years after Maunaulu ceased, in 1983 the Pu’u’ō’ō eruption began, producing regular spectacles of lava explosions. Far surpassing its predecessor, it lasted until 30 April 2018, when the crater floor and lava lake catastrophically collapsed.

    What’s particularly wild is that’s not even the longest continually active volcano on our planet. According to Guinness World Records, this honor belongs to Mt Stromboli in Italy, that’s been going since at least the 7th century BCE.

    You can see the full gallery of the picturesque Maunaulu eruption on the USGS website.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Created by an act of Congress in 1879, the The United States Geological Survey (US) has evolved over the ensuing 125 years, matching its talent and knowledge to the progress of science and technology. The USGS is the sole science agency for the Department of the Interior. It is sought out by thousands of partners and customers for its natural science expertise and its vast earth and biological data holdings.

    On March 3, 1879, we were established by the passing of the Organic Act through Congress. Our main responsibilities were to map public lands, examine geological structure, and evaluate mineral resources. Over the next century, our mission expanded to include the research of groundwater, ecosystems, environmental health, natural hazards, and climate and land use change.

     
  • richardmitnick 10:18 am on November 14, 2021 Permalink | Reply
    Tags: "Dark Matter Birthed More of Itself From Regular Matter Claims Wild New Paper", , , , Science Alert (US), The University of Oslo [Universitetet i Oslo](NO)   

    From The University of Oslo [Universitetet i Oslo](NO) via Science Alert (US) : “Dark Matter Birthed More of Itself From Regular Matter Claims Wild New Paper” 

    From The University of Oslo [Universitetet i Oslo](NO)

    via

    ScienceAlert

    Science Alert (US)

    14 NOVEMBER 2021
    DAVID NIELD

    1
    Dark matter ‘clumps’ between galaxies. S. Epps & M. Hudson/The University of Waterloo (CA))

    There’s a lot we still don’t know about Dark Matter – that mysterious, invisible mass that could make up as much as 85 percent of everything around us – but a new paper outlines a rather unusual hypothesis about the very creation of the stuff.

    In short: dark matter creates dark matter. The idea is that at some point in the early stages of the Universe, dark matter particles were able to create more dark matter particles out of particles of regular matter, which would go some way to explaining why there’s now so much of the stuff about.

    The new research builds on earlier proposals [Physical Review Letters] of a ‘thermal bath’, where regular matter in the form of plasma produced the first bits of dark matter – initial particles which could then have had the power to transform heat bath particles into more dark matter.

    “This leads to an exponential growth of the dark matter number density in close analogy to other familiar exponential growth processes in nature,” the international team of physicists, led by Torsten Bringmann from the University of Oslo in Norway, write in their newly published paper.

    There are some unanswered questions about this new hypothesis, as is normal for anything to do with dark matter, but importantly it fits with the observations of dark matter we have today via the cosmic microwave background (CMB).

    CMB per European Space Agency(EU) Planck.

    While we can’t actually see dark matter directly, the behavior of the Universe, together with the electromagnetic radiation that makes up the CMB, strongly suggests that dark matter is out there somewhere – and in seriously large amounts.

    There’s a variety of scenarios attempting to explain conditions that could constrain the proportions of dark matter we see. One, called a freeze-in scenario, proposes that however dark matter might have appeared in the hot bath of early plasma, nothing cancelled it out. As the Universe expanded, its gradual generation simply ceased, forever locking in a certain amount.

    By contrast, a freeze-out model suggests dark matter appeared as rapidly as normal matter, but reached an equilibrium once antiparticles cancelled some out. Once again, the cooling of the expanding Universe chilled its generation but also its ability to quickly annihilate, leaving us with a set amount.

    This new study proposes yet another possibility – more or less in between the two extremes. If it’s right, it would mean the amount of dark matter grew very quickly as the Universe expanded, with this growth slowing and eventually stopping as the expansion of the Universe has slowed down.

    With regular matter and dark matter becoming more spaced out from one another over time, this dark matter production line has petered out. What’s more, according to the researchers, somewhere out there in the CMB there should be proof that this theory is correct, so the next job is to find it.

    We have hugely sensitive dark matter detectors monitoring the cosmos, so it might not be too long before we hear more about this new approach to understanding dark matter production – in turn, teaching us more about the creation and the growth of the Universe.

    “Our mechanism complements both freeze-in and freeze-out thermal production scenarios in a generic way,” write the researchers. “Further, and detailed, exploration of this new way of producing dark matter from the thermal bath thus appears highly warranted.”

    The research has been published in Physical Review Letters.

    See the full article here.

    ______________________________________________________
    Dark Matter Background
    Fritz Zwicky discovered Dark Matter in the 1930s when observing the movement of the Coma Cluster., Vera Rubin a Woman in STEM, denied the Nobel, some 30 years later, did most of the work on Dark Matter.

    Fritz Zwicky.
    Coma cluster via NASA/ESA Hubble, the original example of Dark Matter discovered during observations by Fritz Zwicky and confirmed 30 years later by Vera Rubin.
    In modern times, it was astronomer Fritz Zwicky, in the 1930s, who made the first observations of what we now call dark matter. His 1933 observations of the Coma Cluster of galaxies seemed to indicated it has a mass 500 times more than that previously calculated by Edwin Hubble. Furthermore, this extra mass seemed to be completely invisible. Although Zwicky’s observations were initially met with much skepticism, they were later confirmed by other groups of astronomers.

    Thirty years later, astronomer Vera Rubin provided a huge piece of evidence for the existence of dark matter. She discovered that the centers of galaxies rotate at the same speed as their extremities, whereas, of course, they should rotate faster. Think of a vinyl LP on a record deck: its center rotates faster than its edge. That’s what logic dictates we should see in galaxies too. But we do not. The only way to explain this is if the whole galaxy is only the center of some much larger structure, as if it is only the label on the LP so to speak, causing the galaxy to have a consistent rotation speed from center to edge.

    Vera Rubin, following Zwicky, postulated that the missing structure in galaxies is dark matter. Her ideas were met with much resistance from the astronomical community, but her observations have been confirmed and are seen today as pivotal proof of the existence of dark matter.
    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science).

    Vera Rubin measuring spectra at the Department of Terrestrial Magnetism at the Carnegie Institution in Washington in about 1970. (Emilio Segre Visual Archives AIP SPL).

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970.

    Dark Matter Research

    LBNL LZ Dark Matter Experiment (US) xenon detector at Sanford Underground Research Facility(US) Credit: Matt Kapust.

    Lamda Cold Dark Matter Accerated Expansion of The universe http scinotions.com the-cosmic-inflation-suggests-the-existence-of-parallel-universes. Credit: Alex Mittelmann.

    DAMA at Gran Sasso uses sodium iodide housed in copper to hunt for dark matter LNGS-INFN.

    Yale HAYSTAC axion dark matter experiment at Yale’s Wright Lab.

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB (CA) deep in Sudbury’s Creighton Mine

    The LBNL LZ Dark Matter Experiment (US) Dark Matter project at SURF, Lead, SD, USA.

    DAMA-LIBRA Dark Matter experiment at the Italian National Institute for Nuclear Physics’ (INFN’s) Gran Sasso National Laboratories (LNGS) located in the Abruzzo region of central Italy.

    DARWIN Dark Matter experiment. A design study for a next-generation, multi-ton dark matter detector in Europe at the University of Zurich.

    PandaX II Dark Matter experiment at Jin-ping Underground Laboratory (CJPL) in Sichuan, China.

    Inside the Axion Dark Matter eXperiment U Washington (US) Credit : Mark Stone U. of Washington. Axion Dark Matter Experiment.
    ______________________________________________________

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Oslo [Universitetet i Oslo](NO), until 1939 named the Royal Frederick University is the oldest university in Norway, located in the Norwegian capital of Oslo. Until 1 January 2016 it was the largest Norwegian institution of higher education in terms of size, now surpassed only by the Norwegian University of Science and Technology [Norges teknisk-naturvitenskapelige universitet](NO). The Academic Ranking of World Universities has ranked it the 58th best university in the world and the third best in the Nordic countries. In 2015, the Times Higher Education World University Rankings ranked it the 135th best university in the world and the seventh best in the Nordics. While in its 2016, Top 200 Rankings of European Universities, the Times Higher Education listed the University of Oslo at 63rd, making it the highest ranked Norwegian university.

    The university has approximately 27,700 students and employs around 6,000 people. Its faculties include (Lutheran) Theology (with the Lutheran Church of Norway having been Norway’s state church since 1536); Law; Medicine; Humanities; Mathematics; Natural Sciences; Social Sciences; Dentistry; and Education. The university’s original neoclassical campus is located in the centre of Oslo. It is currently occupied by the Faculty of Law. Most of the university’s other faculties are located at the newer Blindern campus in the suburban West End. The Faculty of Medicine is split between several university hospitals in the Oslo area. The university also includes some formally independent, affiliated institutes such as the Centre for International Climate and Environmental Research (CICERO); Norwegian Centre for Violence and Traumatic Stress Studies; and the Frisch Centre.

    The university was founded in 1811 and was modeled after the University of Copenhagen [Københavns Universitet](DK) and the recently established Humboldt University of Berlin [Humboldt-Universität zu Berlin](DE). It was originally named for King Frederick VI of Denmark and Norway, and received its current name in 1939.

    The Nobel Peace Prize was awarded in the university’s Atrium, from 1947 to 1989 and will be so again in 2020, making it the only university in the world to be involved in awarding a Nobel Prize. Since 2003, the Abel Prize is awarded in the Atrium. Five researchers affiliated with the university have been Nobel laureates.

     
  • richardmitnick 10:19 am on November 10, 2021 Permalink | Reply
    Tags: "There is a Mysterious Barrier Keeping Cosmic Rays Out of The Galactic Center", Astronomers expect that the galactic center is an important source of cosmic rays., Science Alert (US), , The galactic center is a high-energy particle accelerator-or at least something in the region is., The galactic center is a zone of mystery., There are a number of objects in the galactic center that could act as cosmic ray accelerators.   

    From The Chinese Academy of Sciences [中国科学院] (CN) via Science Alert (US) : “There is a Mysterious Barrier Keeping Cosmic Rays Out of The Galactic Center” 

    From The Chinese Academy of Sciences [中国科学院] (CN)

    via

    ScienceAlert

    Science Alert (US)

    9 NOVEMBER 2021
    MICHELLE STARR

    1
    The galactic center in radio and X-rays. Credit: The National Aeronautics and Space Agency(US)/The Chandra X-ray Center (US)/University of Massachusettes (US)/D. Wang et al./The National Research Foundation – SARAO(SA)/SKA MeerKAT (SA))

    The center of the Milky Way is a powerful particle accelerator, new research has revealed – but there’s also some unknown mechanism blocking cosmic rays from penetrating the vast cloud called the central molecular zone.

    This finding could help us better understand the origins of cosmic rays – particles such as protons and atomic nuclei that constantly stream through space at almost the speed of light.

    The galactic center is a zone of mystery. We have a decent idea of what’s in there, but it’s so thick with dust that we can’t study it in a range of wavelengths, from soft X-rays through to visible light. This has placed some limitations on what we can and can’t see.

    Astronomers expect that the galactic center is an important source of cosmic rays. These are protons and nuclei that have been stripped of electrons and accelerated to relativistic speeds by powerful magnetic fields. There are a number of objects in the galactic center that could act as cosmic ray accelerators: supernova remnants, pulsar wind nebulae, and the supermassive hole at the Milky Way’s heart, Sagittarius A*.

    SGR A* Credit: Pennsylvania State University(US) and National Aeronautics Space Agency(US) Chandra X-ray Observatory (US)

    According to observation data and modeling, the cosmic ray distribution throughout the Milky Way should be smooth, and more or less steady. Cosmic rays emerge from accelerators and propagate in the galactic magnetic field, where they are likely slowed and re-accelerated to result in what astronomers call a cosmic ray sea [Physical Review D].

    In order to study how cosmic rays are accelerated and transported, a source of fresh cosmic rays is required.

    Luckily, cosmic rays are very energetic. This means we can detect them in the galactic center, because that energy range produces light in the limited wavelength range that penetrates the dust there.

    Cosmic rays can interact with the interstellar medium – gas and dust that hangs around in the space between the stars – and this interaction in turn produces high-energy gamma-ray photons, with about 10 percent of the energy of their cosmic ray parents.

    Led by astronomer Xiaoyuan Huang of the Chinese Academy of Sciences, a team of researchers looked at the gamma radiation in the central molecular cloud of the Milky Way using data from the Fermi Large Area Telescope, hoping to find these sources of fresh cosmic rays.

    National Aeronautics and Space Administration(US) Fermi Large Area Telescope

    National Aeronautics and Space Administration(US)/Fermi Gamma Ray Space Telescope.

    They found gamma rays that did suggest, as expected, that the galactic center is a high-energy particle accelerator-or at least something in the region is. But they also found something really surprising.

    According to the team’s calculations, the density of cosmic rays in the central molecular cloud is lower than the density of the cosmic ray sea. This suggests the presence of some kind of barrier that is preventing cosmic rays from penetrating the central molecular cloud.

    Exactly what this barrier consists of will need to be the subject of future research, but there are several intriguing possibilities.

    Molecular clouds are complicated places. The collapse of denser parts of the cloud can result in compression of magnetic fields; that could be a barrier. Another could be magnetohydrodynamic turbulence.

    Here in the Solar System, cosmic rays are modulated by the solar wind [Progress of Theoretical Physics]. It’s possible that, in the galactic center, the galactic wind fulfils a similar role. The team calculated the cosmic ray density in the presence of a galactic wind, and returned a similar result to their analysis of the gamma ray data.

    Future work to explore this phenomenon in more detail may help rule out some of the mechanisms that could be causing it.

    In addition, more detailed, three-dimensional modeling of the galactic center could help shed more light on the origin and transport of cosmic rays in the Milky Way, the researchers say. There’s always more out there to be found, indeed.

    The research has been published in Nature Communications.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Chinese Academy of Sciences [中国科学院] (CN) is the linchpin of China’s drive to explore and harness high technology and the natural sciences for the benefit of China and the world. Comprising a comprehensive research and development network, a merit-based learned society and a system of higher education, CAS brings together scientists and engineers from China and around the world to address both theoretical and applied problems using world-class scientific and management approaches.

    Since its founding, CAS has fulfilled multiple roles — as a national team and a locomotive driving national technological innovation, a pioneer in supporting nationwide S&T development, a think tank delivering S&T advice and a community for training young S&T talent.

    Now, as it responds to a nationwide call to put innovation at the heart of China’s development, CAS has further defined its development strategy by emphasizing greater reliance on democratic management, openness and talent in the promotion of innovative research. With the adoption of its Innovation 2020 programme in 2011, the academy has committed to delivering breakthrough science and technology, higher caliber talent and superior scientific advice. As part of the programme, CAS has also requested that each of its institutes define its “strategic niche” — based on an overall analysis of the scientific progress and trends in their own fields both in China and abroad — in order to deploy resources more efficiently and innovate more collectively.

    As it builds on its proud record, CAS aims for a bright future as one of the world’s top S&T research and development organizations.

     
  • richardmitnick 8:43 am on October 27, 2021 Permalink | Reply
    Tags: "Gigantic Movie Monster Discovered Lurking in Space... If You Look Closely", Science Alert (US), , Spitzer at NASA-JPL/Caltech   

    From Spitzer at NASA-JPL/Caltech via Science Alert (US) : “Gigantic Movie Monster Discovered Lurking in Space… If You Look Closely” 

    NASA Spitzer

    From Spitzer at NASA-JPL/Caltech

    via

    ScienceAlert

    Science Alert (US)

    27 OCTOBER 2021
    DAVID NIELD

    1
    A nebula image captured by the Spitzer Space Telescope. Credit: NASA/JPL-Caltech.

    We’ve seen plenty of awe-inspiring images of space captured by telescopes and spacecraft in the past: whether it’s a supernova blast wave, the textures of a planet, or pillars of interstellar gas and dust, there’s a virtually endless stream of fascinating pictures available for us to pore over.

    Sometimes though there’s something more hidden in the patterns of stars and light. Take a look at the image below, for example, and see if it suggests anything to you. It’s an image captured by the NASA Spitzer Space Telescope, which was operational from 2003 to 2020.

    Getting anything yet? We’ll give you a clue: Think about monsters… specifically monsters originating from Japanese films of the 1950s. You might have to squint a little and use your imagination before we tell you any more.

    3
    The nebula, hiding a certain someone. Credit: NASA/JPL-Caltech.

    In terms of specifics, the picture shows a nebula nursery of stars located in the Sagittarius constellation, along the plane of the Milky Way. The bright region in the lower left (which looks like it might be being held by a massive creature?) is a star-forming region known as W33, and is around 7,800 light-years away from Earth.

    The picture was captured as part of Spitzer’s GLIMPSE Survey, which stands for Galactic Legacy Infrared Mid-Plane Survey Extraordinaire. Although Spitzer is now retired, the images it collected are still being analyzed.

    One of those doing the analyzing is astronomer Robert Hurt, from The California Institute of Technology (US), and he’s managed to spot something in the image. As you might have guessed by now, Hurt thinks there’s a definite hint of Godzilla in there.

    “I wasn’t looking for monsters,” says Hurt. “I just happened to glance at a region of sky that I’ve browsed many times before, but I’d never zoomed in on. Sometimes if you just crop an area differently, it brings out something that you didn’t see before. It was the eyes and mouth that roared ‘Godzilla’ to me.”

    3
    The monster revealed. Credit: NASA/JPL-Caltech.

    Pareidolia is the tendency to see something meaningful in a meaningless image, and it happens quite often – including in pictures of the cosmos: Take a look at the Spitzer images that resemble a jack-o’-lantern, a black widow spider, or the Starship Enterprise, for example.

    The color processing helps: here blue, cyan, green, and red are used to represent different wavelengths of infrared light, with yellow and white combinations of those wavelengths. Blue and cyan show light emitted by stars, green shows dust and organic molecules called hydrocarbons, and red shows warm dust heated by stars or supernovae.

    Work continues to catalog and examine the data collected by Spitzer, and to raise awareness of its findings – and sometimes that means using an iconic sea monster to help tell a story.

    “It’s one of the ways that we want people to connect with the incredible work that Spitzer did,” says Hurt.

    “I look for compelling areas that can really tell a story. Sometimes it’s a story about how stars and planets form, and sometimes it’s about a giant monster rampaging through Tokyo.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Spitzer Space Telescope is a NASA mission managed by the Jet Propulsion Laboratory located on the campus of the California Institute of Technology and part of NASA’s Infrared Processing and Analysis Center.

    NASA JPL Icon

    Caltech Logo

     
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