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  • richardmitnick 4:26 pm on October 1, 2014 Permalink | Reply
    Tags: , Astrophysics, , , ,   

    From Don Lincoln at Fermilab: “The Big Bang Theory” video 


    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    From Don Lincoln at Fermilab

    FNAL Don Lincoln

    The Big Bang is the name of the most respected theory of the creation of the universe. Basically, the theory says that the universe was once smaller and denser and has been expending for eons. One common misconception is that the Big Bang theory says something about the instant that set the expansion into motion, however this isn’t true. In this video, Fermilab’s Dr. Don Lincoln tells about the Big Bang theory and sketches some speculative ideas about what caused the universe to come into existence.

    Watch, enjoy, learn.

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    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics.

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  • richardmitnick 2:43 pm on October 1, 2014 Permalink | Reply
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    From Cassini: “Swirling Cloud at Titan’s Pole is Cold and Toxic “ 

    NASA Cassini Spacecraft

    Cassini-Huygens

    Scientists analyzing data from NASA’s Cassini mission have discovered that a giant, toxic cloud is hovering over the south pole of Saturn’s largest moon, Titan, after the atmosphere there cooled dramatically.

    titan
    Spectral Map of Titan with Polar Vortex. These two views of Saturn’s moon Titan show the southern polar vortex, a huge, swirling cloud that was first observed by NASA’s Cassini spacecraft in 2012.
    The view at left is a spectral map of Titan obtained with the Cassini Visual and Infrared Mapping Spectrometer (VIMS) on Nov. 29, 2012. The inset image is a natural-color close-up of the polar vortex taken by Cassini’s wide-angle camera.

    vims

    Three distinct components are evident in the VIMS image, represented by different colors: the surface of Titan (orange, near center), atmospheric haze along the limb (light green, at top) and the polar vortex (blue, at lower left).

    To the VIMS instrument, the spectrum of the southern polar vortex shows a remarkable difference with respect to other portions of Titan’s atmosphere: a signature of frozen hydrogen cyanide molecules (HCN). This discovery has suggested to researchers that the atmosphere of Titan’s southern hemisphere is cooling much faster than expected. Observing seasonal shifts like this in the moon’s climate is a major goal for Cassini’s current extended mission.

    The scientists found that this giant polar vortex contains frozen particles of the toxic compound hydrogen cyanide, or HCN.

    “The discovery suggests that the atmosphere of Titan’s southern hemisphere is cooling much faster than we expected,” said Remco de Kok of Leiden Observatory and SRON Netherlands Institute for Space Research, lead author of the study published today in the journal Nature.

    Titan is the only moon in the solar system that is cloaked in a dense atmosphere. Like our home planet, Earth, Titan experiences seasons. As it makes its 29-year orbit around the sun along with Saturn, each season lasts about seven Earth years. The most recent seasonal switch occurred in 2009, when winter gave way to spring in the northern hemisphere, and summer transitioned to autumn in the southern hemisphere.

    In May 2012, while Titan’s southern hemisphere was experiencing autumn, images from Cassini revealed a huge swirling cloud, several hundred miles across, taking shape above Titan’s south pole. This polar vortex appears to be an effect of the change of season.

    A puzzling detail about the swirling cloud is its altitude, some 200 miles (about 300 kilometers) above Titan’s surface, where scientists thought the temperature was too warm for clouds to form. “We really didn’t expect to see such a massive cloud so high in the atmosphere,” said de Kok.

    Keen to understand what could give rise to this mysterious cloud, the scientists dove into Cassini’s observations and found an important clue in the spectrum of sunlight reflected by Titan’s atmosphere.

    A spectrum splits the light from a celestial body into its constituent colors, revealing signatures of the elements and molecules present. Cassini’s visual and infrared mapping spectrometer (VIMS) maps the distribution of chemical compounds in Titan’s atmosphere and on its surface.

    “The light coming from the polar vortex showed a remarkable difference with respect to other portions of Titan’s atmosphere,” says de Kok. “We could clearly see a signature of frozen HCN molecules.”

    As a gas, HCN is present in small amounts in the nitrogen-rich atmosphere of Titan. Finding these molecules in the form of ice was surprising, as HCN can condense to form frozen particles only if the atmospheric temperature is as cold as minus 234 degrees Farenheit (minus 148 degrees Celsius). This is about 200 degrees Fahrenheit (about 100 degrees Celsius) colder than predictions from current theoretical models of Titan’s upper atmosphere.

    To check whether such low temperatures were actually possible, the team looked at observations from Cassini’s composite infrared spectrometer (CIRS), which measures atmospheric temperature at different altitudes. Those data showed that the southern hemisphere of Titan has been cooling rapidly, making it possible to reach the cold temperature needed to form the giant toxic cloud seen on the south pole.

    Atmospheric circulation has been drawing large masses of gas towards the south since the change of season in 2009. As HCN gas becomes more concentrated there, its molecules shine brightly at infrared wavelengths, cooling the surrounding air in the process. Another factor contributing to this cooling is the reduced exposure to sunlight in Titan’s southern hemisphere as winter approaches there.

    “These fascinating results from a body whose seasons are measured in years rather than months provide yet another example of the longevity of the remarkable Cassini spacecraft and its instruments,” said Earl Maize, Cassini project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California. “We look forward to further revelations as we approach summer solstice for the Saturn system in 2017.”

    See the full article here.

    Cassini completed its initial four-year mission to explore the Saturn System in June 2008 and the first extended mission, called the Cassini Equinox Mission, in September 2010. Now, the healthy spacecraft is seeking to make exciting new discoveries in a second extended mission called the Cassini Solstice Mission.

    The mission’s extension, which goes through September 2017, is named for the Saturnian summer solstice occurring in May 2017. The northern summer solstice marks the beginning of summer in the northern hemisphere and winter in the southern hemisphere. Since Cassini arrived at Saturn just after the planet’s northern winter solstice, the extension will allow for the first study of a complete seasonal period.

    Cassini launched in October 1997 with the European Space Agency’s Huygens probe. The probe was equipped with six instruments to study Titan, Saturn’s largest moon. It landed on Titan’s surface on Jan. 14, 2005, and returned spectacular results.

    Meanwhile, Cassini’s 12 instruments have returned a daily stream of data from Saturn’s system since arriving at Saturn in 2004.

    Among the most important targets of the mission are the moons Titan and Enceladus, as well as some of Saturn’s other icy moons. Towards the end of the mission, Cassini will make closer studies of the planet and its rings.

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  • richardmitnick 8:46 am on October 1, 2014 Permalink | Reply
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    From ESO: “Wild Ducks Take Flight in Open Cluster” 


    European Southern Observatory

    The Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO’s La Silla Observatory in Chile has taken this beautiful image, dappled with blue stars, of one of the most star-rich open clusters currently known — Messier 11, also known as NGC 6705 or the Wild Duck Cluster.

    m11

    ESO Wide Field Imager 2.2m LaSilla
    WFI

    ESO 2.2 meter telescope
    ESO 2.2 meter telescope interior
    2.2 meter telescope at LaSilla

    ESO LaSilla Long View
    ESO at LaSilla

    Messier 11 is an open cluster, sometimes referred to as a galactic cluster, located around 6000 light-years away in the constellation of Scutum (The Shield). It was first discovered by German astronomer Gottfried Kirch in 1681 at the Berlin Observatory, appearing as nothing more than a fuzzy blob through the telescope. It wasn’t until 1733 that the blob was first resolved into separate stars by the Reverend William Derham in England, and Charles Messier added it to his famous catalogue in 1764.

    Messier was a comet hunter and the catalogue came into being as he was frustrated by constantly observing fixed, diffuse objects that looked like comets (for example, objects that we now know to be clusters, galaxies and nebulae). He wanted a record in order to avoid accidentally observing them again and confusing them with possible new comets. This particular stellar cluster was noted down as the eleventh such object — hence the name of Messier 11.

    Open clusters are typically found lying in the arms of spiral galaxies or in the denser regions of irregular galaxies, where star formation is still common. Messier 11 is one of the most star-rich and compact of the open clusters, being almost 20 light-years across and home to close to 3000 stars. Open clusters are different to globular clusters, which tend to be very dense, tightly bound by gravity, and contain hundreds of thousands of very old stars — some of which are nearly as old as the Universe itself.

    Studying open clusters is great way to test theories of stellar evolution, as the stars form from the same initial cloud of gas and dust and are therefore very similar to one another — they all have roughly the same age, chemical composition, and are all the same distance away from Earth. However, each star in the cluster has a different mass, with the more massive stars evolving much faster than their lower mass counterparts as they use up all of their hydrogen much sooner.

    In this way, direct comparisons between the different evolutionary stages can be made within the same cluster: for example, does a 10 million year old star with the same mass as the Sun evolve in a different way to another star that is the same age, but half as massive? In this sense, open clusters are the closest thing astronomers have to “laboratory conditions”.

    Because the stars within open clusters are very loosely bound to one another, individuals are very susceptible to being ejected from the main group due to the effect of gravity from neighbouring celestial objects. NGC 6705 is already at least 250 million years old, so in a few more million years it is likely that this Wild Duck formation will disperse, and the cluster will break up and merge into its surroundings [1].

    Notes

    [1] The alternative and evocative name for NGC 6705, the Wild Duck Cluster, came about in the 19th century. When the cluster was seen through a small telescope it was noticed that the brightest stars formed an open triangle pattern on the sky that resembled ducks flying in formation.

    See the full article here.

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    ESO, European Southern Observatory, builds and operates a suite of the world’s most advanced ground-based astronomical telescopes.

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  • richardmitnick 7:50 pm on September 30, 2014 Permalink | Reply
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    From Astronomy: “New molecule found in space connotes life origins” 

    Astronomy magazine

    Astronomy Magazine

    September 29, 2014
    No Writer Credit
    Cornell University, Ithaca, New York

    Like finding a molecular needle in a cosmic haystack, astronomers have detected radio waves emitted by isopropyl cyanide.

    Hunting from a distance of 27,000 light-years, astronomers have discovered an unusual carbon-based molecule — one with a branched structure — contained within a giant gas cloud in interstellar space. Like finding a molecular needle in a cosmic haystack, astronomers have detected radio waves emitted by isopropyl cyanide. The discovery suggests that the complex molecules needed for life may have their origins in interstellar space.

    cyan
    Dust and molecules in the central region of our galaxy: The background image shows the dust emission in a combination of data obtained with the APEX telescope and the Planck space observatory at a wavelength around 860 micrometers. The organic molecule iso-propyl cyanide with a branched carbon backbone (i-C3H7CN, left) as well as its straight-chain isomer normal-propyl cyanide (n-C3H7CN, right) were both detected with the Atacama Large Millimeter/submillimeter Array in the star-forming region Sgr B2, about 300 light years away from the galactic center Sgr A*.
    MPIfR/A. Weiß (background image); University of Cologne/M. Koerber (molecular models); MPIfR/A. Belloche (montage)

    Using the Atacama Large Millimeter/submillimeter Array (ALMA), researchers studied the gaseous star-forming region Sagittarius B2.

    ALMA Array
    ALMA

    Organic molecules usually found in these star-forming regions consist of a single “backbone” of carbon atoms arranged in a straight chain. But the carbon structure of isopropyl cyanide branches off, making it the first interstellar detection of such a molecule, said Rob Garrod from Cornell University in Ithaca, New York.

    This detection opens a new frontier in the complexity of molecules that can be formed in interstellar space and that might ultimately find their way to the surfaces of planets, said Garrod. The branched carbon structure of isopropyl cyanide is a common feature in molecules that are needed for life — such as amino acids, which are the building blocks of proteins. This new discovery lends weight to the idea that biologically crucial molecules, like amino acids that are commonly found in meteorites, are produced early in the process of star formation — even before planets such as Earth are formed.

    Garrod, along with Arnaud Belloche and Karl Menten, both of the Max Planck Institute for Radio Astronomy, and Holger Müller of the University of Cologne, sought to examine the chemical makeup of Sagittarius B2, a region close to the Milky Way’s galactic center and an area rich in complex interstellar organic molecules.

    With ALMA, the group conducted a full spectral survey looking for fingerprints of new interstellar molecules — with sensitivity and resolution 10 times greater than previous surveys.

    The purpose of the ALMA Observatory is to search for cosmic origins through an array of 66 sensitive radio antennas from the high elevation and dry air of northern Chile’s Atacama Desert. The array of radio telescopes works together to form a gigantic “eye” peering into the cosmos.

    “Understanding the production of organic material at the early stages of star formation is critical to piecing together the gradual progression from simple molecules to potentially life-bearing chemistry,” said Belloche.

    About 50 individual features for isopropyl cyanide and 120 for normal-propyl cyanide — its straight-chain sister molecule — were identified in the ALMA spectrum of the Sagittarius B2 region. The two molecules — isopropyl cyanide and normal-propyl cyanide — are also the largest molecules yet detected in any star-forming region.

    See the full article here..

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  • richardmitnick 5:41 pm on September 30, 2014 Permalink | Reply
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    From SPACE.com: “Search for Alien Life Should Target Water, Oxygen and Chlorophyll” 

    space-dot-com logo

    SPACE.com

    September 30, 2014
    Mike Wall

    The next generation of space telescopes hunting for signs of extraterrestrial life should focus on water, then oxygen and then alien versions of the plant chemical chlorophyll, a new study suggests.

    In the past 20 years or so, astronomers have confirmed the existence of nearly 2,000 worlds outside Earth’s solar system. Many of these exoplanets lie in the habitable zones of stars, areas potentially warm enough for the worlds to harbor liquid water on their surfaces. Astrobiologists hope that life may someday be spotted on such alien planets, since there is life pretty much everywhere water exists on Earth.

    One strategy to discover signs of such alien life involves looking for ways that organisms might change a world’s appearance. For example, chemicals typically shape what are known as the spectra seen from planets by adding or removing wavelengths of light. Alien-hunting telescopes could look for spectra that reveal chemicals associated with life. In other words, these searches would focus on biosignatures — chemicals or combinations of chemicals that life could produce, but that processes other than life could not or would be unlikely to create.

    Astrophysicists Timothy Brandt and David Spiegel at the Institute for Advanced Study in Princeton, New Jersey, sought to see how challenging it might be to conclusively identify signatures of water, oxygen and chlorophyll — the green pigment that plants use to convert sunlight to energy — on a distant twin of Earth using a future off-Earth instrument such as NASA’s proposed Advanced Technology Large-Aperture Space Telescope (ATLAST).

    atlast
    8-meter monolithic mirror telescope (credit: MSFC Advanced Concepts Office)
    again
    16-meter segmented mirror telescope (credit: Northrop Grumman Aerospace Systems & NASA/STScI)
    two conceptual schemes for ATLAST

    The scientists found that water would be the easiest to detect.

    “Water is a very common molecule, and I think a mission to take spectra of exoplanets should certainly look for water,” said Brandt, the lead study author. “Indeed, we have found water in a few gas giants more massive than Jupiter orbiting other stars.”

    In comparison, oxygen is more difficult to detect than previously thought, requiring scientific instruments approximately twice as sensitive as those needed to detect water and significantly better at discriminating between similar colors of light.

    “Oxygen, however, has only been a large part of Earth’s atmosphere for a few hundred million years,” Brandt said. “If we see it in an exoplanet, it probably points to life, but not finding oxygen certainly does not mean that the planet is sterile.”

    Although a well-designed space telescope could detect water and oxygen on a nearby Earth twin, the astrophysicists found the instrument would need to be significantly more sensitive, or very lucky, to see chlorophyll. Identifying this chemical typically requires scientific instruments about six times more sensitive than those needed for oxygen. Chlorophyll becomes as detectable as oxygen only when an exoplanet has a lot of vegetation and/or little in the way of cloud cover, researchers said.

    Chlorophyll slightly reddens the light from Earth. If extraterrestrial life does convert sunlight to energy as plants do, scientists expect that the alien process might use a different pigment than chlorophyll. But alien photosynthesis could also slightly redden planets, just as chlorophyll does.

    “Light comes in packets called photons, and only photons with at least a certain amount of energy are useful for photosynthesis,” Brandt said. Chlorophyll reflects photons that are too red and low in energy to be used for photosynthesis, and it may be reasonable to assume that extraterrestrial pigments would do the same thing, Brandt noted.

    The researchers suggest a strategy for discovering Earthlike alien life that first looks for water, then oxygen on the more favorable planets and finally chlorophyll on only the most exceptionally promising worlds.

    “The goal of a future space telescope will be primarily to detect water and oxygen on a planet around a nearby star,” Brandt said. “The construction and launch of such a telescope will probably cost at least $10 billion and won’t happen for at least 20 years — a lot of technology development needs to happen first — but it could be the most exciting mission of my lifetime.”

    Brandt and Spiegel detailed their findings online Sept. 1 in the journal Proceedings of the National Academy of Sciences.

    See the full article here.

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  • richardmitnick 4:55 pm on September 30, 2014 Permalink | Reply
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    From NASA/SWIFT: “NASA’s Swift Mission Observes Mega Flares from a Mini Star” 

    NASA Swift Banner

    NASA SWIFT Telescope

    NASA Swift

    September 30, 2014
    Francis Reddy
    NASA’s Goddard Space Flight Center, Greenbelt, Maryland

    On April 23, NASA’s Swift satellite detected the strongest, hottest, and longest-lasting sequence of stellar flares ever seen from a nearby red dwarf star. The initial blast from this record-setting series of explosions was as much as 10,000 times more powerful than the largest solar flare ever recorded.

    “We used to think major flaring episodes from red dwarfs lasted no more than a day, but Swift detected at least seven powerful eruptions over a period of about two weeks,” said Stephen Drake, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who gave a presentation on the “superflare” at the August meeting of the American Astronomical Society’s High Energy Astrophysics Division. “This was a very complex event.”

    At its peak, the flare reached temperatures of 360 million degrees Fahrenheit (200 million Celsius), more than 12 times hotter than the center of the sun.


    In April 2014, NASA’s Swift mission detected a massive superflare from a red dwarf star in the binary system DG CVn, located about 60 light-years away. Astronomers Rachel Osten of the Space Telescope Science Institute and Stephen Drake of NASA Goddard discuss this remarkable event.
    Image Credit: NASA’s Goddard Space Flight Center/S. Wiessinger

    The “superflare” came from one of the stars in a close binary system known as DG Canum Venaticorum, or DG CVn for short, located about 60 light-years away. Both stars are dim red dwarfs with masses and sizes about one-third of our sun’s. They orbit each other at about three times Earth’s average distance from the sun, which is too close for Swift to determine which star erupted.

    “This system is poorly studied because it wasn’t on our watch list of stars capable of producing large flares,” said Rachel Osten, an astronomer at the Space Telescope Science Institute in Baltimore and a deputy project scientist for NASA’s James Webb Space Telescope, now under construction. “We had no idea DG CVn had this in it.”

    Most of the stars lying within about 100 light-years of the solar system are, like the sun, middle-aged. But a thousand or so young red dwarfs born elsewhere drift through this region, and these stars give astronomers their best opportunity for detailed study of the high-energy activity that typically accompanies stellar youth. Astronomers estimate DG CVn was born about 30 million years ago, which makes it less than 0.7 percent the age of the solar system.

    Stars erupt with flares for the same reason the sun does. Around active regions of the star’s atmosphere, magnetic fields become twisted and distorted. Much like winding up a rubber band, these allow the fields to accumulate energy. Eventually a process called magnetic reconnection destabilizes the fields, resulting in the explosive release of the stored energy we see as a flare. The outburst emits radiation across the electromagnetic spectrum, from radio waves to visible, ultraviolet and X-ray light.

    At 5:07 p.m. EDT on April 23, the rising tide of X-rays from DG CVn’s superflare triggered Swift’s Burst Alert Telescope (BAT). Within several seconds of detecting a strong burst of radiation, the BAT calculates an initial position, decides whether the activity merits investigation by other instruments and, if so, sends the position to the spacecraft. In this case, Swift turned to observe the source in greater detail, and, at the same time, notified astronomers around the globe that a powerful outburst was in progress.

    “For about three minutes after the BAT trigger, the superflare’s X-ray brightness was greater than the combined luminosity of both stars at all wavelengths under normal conditions,” noted Goddard’s Adam Kowalski, who is leading a detailed study on the event. “Flares this large from red dwarfs are exceedingly rare.”

    The star’s brightness in visible and ultraviolet light, measured both by ground-based observatories and Swift’s Optical/Ultraviolet Telescope, rose by 10 and 100 times, respectively. The initial flare’s X-ray output, as measured by Swift’s X-Ray Telescope, puts even the most intense solar activity recorded to shame.

    The largest solar explosions are classified as extraordinary, or X class, solar flares based on their X-ray emission. “The biggest flare we’ve ever seen from the sun occurred in November 2003 and is rated as X 45,” explained Drake. “The flare on DG CVn, if viewed from a planet the same distance as Earth is from the sun, would have been roughly 10,000 times greater than this, with a rating of about X 100,000.”

    But it wasn’t over yet. Three hours after the initial outburst, with X-rays on the downswing, the system exploded with another flare nearly as intense as the first. These first two explosions may be an example of “sympathetic” flaring often seen on the sun, where an outburst in one active region triggers a blast in another.

    Over the next 11 days, Swift detected a series of successively weaker blasts. Osten compares the dwindling series of flares to the cascade of aftershocks following a major earthquake. All told, the star took a total of 20 days to settle back to its normal level of X-ray emission.

    How can a star just a third the size of the sun produce such a giant eruption? The key factor is its rapid spin, a crucial ingredient for amplifying magnetic fields. The flaring star in DG CVn rotates in under a day, about 30 or more times faster than our sun. The sun also rotated much faster in its youth and may well have produced superflares of its own, but, fortunately for us, it no longer appears capable of doing so.

    Astronomers are now analyzing data from the DG CVn flares to better understand the event in particular and young stars in general. They suspect the system likely unleashes numerous smaller but more frequent flares and plan to keep tabs on its future eruptions with the help of NASA’s Swift.

    See the full article, with video, here.

    The Swift Gamma-Ray Burst Mission consists of a robotic spacecraft called Swift, which was launched into orbit on November 20, 2004, at 17:16:00 UTC on a Delta II 7320-10C expendable launch vehicle. Swift is managed by the NASA Goddard Space Flight Center, and was developed by an international consortium from the United States, United Kingdom, and Italy. It is part of NASA’s Medium Explorer Program (MIDEX).


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  • richardmitnick 4:10 pm on September 30, 2014 Permalink | Reply
    Tags: , Astrophysics, , , NASA NISAR   

    From NASA: “U.S., India to Collaborate on Mars Exploration, Earth-Observing Mission” 

    NASA

    NASA

    September 30, 2014
    Steve Cole
    Headquarters, Washington
    202-358-0918
    stephen.e.cole@nasa.gov

    In a meeting Tuesday in Toronto, NASA Administrator Charles Bolden and K. Radhakrishnan, chairman of the Indian Space Research Organisation (ISRO), signed two documents to launch a NASA-ISRO satellite mission to observe Earth and establish a pathway for future joint missions to explore Mars.

    two
    NASA Administrator Charles Bolden (left) and Chairman K. Radhakrishnan of the Indian Space Research Organisation signing documents in Toronto on Sept. 30, 2014 to launch a joint Earth-observing satellite mission and establish a pathway for future joint missions to explore Mars. Image Credit: NASA

    While attending the International Astronautical Congress, the two space agency leaders met to discuss and sign a charter that establishes a NASA-ISRO Mars Working Group to investigate enhanced cooperation between the two countries in Mars exploration. They also signed an international agreement that defines how the two agencies will work together on the NASA-ISRO Synthetic Aperture Radar (NISAR) mission, targeted to launch in 2020.

    concept
    An artist’s concept of the planned NASA-ISRO Synthetic Aperture Radar, or NISAR, satellite in orbit, showing the large deployable mesh antenna, solar panels and radar electronics attached to the spacecraft. The mission is a partnership between NASA and the Indian Space Research Organization. Image credit: NASA/JPL-Caltech

    “The signing of these two documents reflects the strong commitment NASA and ISRO have to advancing science and improving life on Earth,” said NASA Administrator Charles Bolden. “This partnership will yield tangible benefits to both our countries and the world.”

    The joint Mars Working Group will seek to identify and implement scientific, programmatic and technological goals that NASA and ISRO have in common regarding Mars exploration. The group will meet once a year to plan cooperative activities, including potential NASA-ISRO cooperation on future missions to Mars.

    Both agencies have newly arrived spacecraft in Mars orbit. NASA’s Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft arrived at Mars Sept. 21. MAVEN is the first spacecraft dedicated to exploring the tenuous upper atmosphere of Mars. ISRO’s Mars Orbiter Mission (MOM), India’s first spacecraft launched to Mars, arrived Sept. 23 to study the Martian surface and atmosphere and demonstrate technologies needed for interplanetary missions.

    NASA Mars MAVEN
    NASA/MAVEN

    India Mars Orbiter Mission
    ISRO MOM

    One of the working group’s objectives will be to explore potential coordinated observations and science analysis between MAVEN and MOM, as well as other current and future Mars missions.

    “NASA and Indian scientists have a long history of collaboration in space science,” said John Grunsfeld, NASA associate administrator for science. “These new agreements between NASA and ISRO in Earth science and Mars exploration will significantly strengthen our ties and the science that we will be able to produce as a result.”

    The joint NISAR Earth-observing mission will make global measurements of the causes and consequences of land surface changes. Potential areas of research include ecosystem disturbances, ice sheet collapse and natural hazards. The NISAR mission is optimized to measure subtle changes of the Earth’s surface associated with motions of the crust and ice surfaces. NISAR will improve our understanding of key impacts of climate change and advance our knowledge of natural hazards.

    NISAR will be the first satellite mission to use two different radar frequencies (L-band and S-band) to measure changes in our planet’s surface less than a centimeter across. This allows the mission to observe a wide range of changes, from the flow rates of glaciers and ice sheets to the dynamics of earthquakes and volcanoes.

    Under the terms of the new agreement, NASA will provide the mission’s L-band synthetic aperture radar (SAR), a high-rate communication subsystem for science data, GPS receivers, a solid state recorder, and a payload data subsystem. ISRO will provide the spacecraft bus, an S-band SAR, and the launch vehicle and associated launch services.

    NASA had been studying concepts for a SAR mission in response to the National Academy of Science’s decadal survey of the agency’s Earth science program in 2007. The agency developed a partnership with ISRO that led to this joint mission. The partnership with India has been key to enabling many of the mission’s science objectives.

    NASA’s contribution to NISAR is being managed and implemented by the agency’s Jet Propulsion Laboratory (JPL) in Pasadena, California.

    NASA and ISRO have been cooperating under the terms of a framework agreement signed in 2008. This cooperation includes a variety of activities in space sciences such as two NASA payloads — the Mini-Synthetic Aperture Radar (Mini-SAR) and the Moon Mineralogy Mapper — on ISRO’s Chandrayaan-1 mission to the moon in 2008. During the operational phase of this mission, the Mini-SAR instrument detected ice deposits near the moon’s northern pole.

    For more information on NASA’s Mars exploration program, visit:

    http://www.nasa.gov/mars

    For more information on the NISAR mission, visit:

    http://nisar.jpl.nasa.gov

    See the full article here.

    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

    President Dwight D. Eisenhower established the National Aeronautics and Space Administration (NASA) in 1958 with a distinctly civilian (rather than military) orientation encouraging peaceful applications in space science. The National Aeronautics and Space Act was passed on July 29, 1958, disestablishing NASA’s predecessor, the National Advisory Committee for Aeronautics (NACA). The new agency became operational on October 1, 1958.

    Since that time, most U.S. space exploration efforts have been led by NASA, including the Apollo moon-landing missions, the Skylab space station, and later the Space Shuttle. Currently, NASA is supporting the International Space Station and is overseeing the development of the Orion Multi-Purpose Crew Vehicle and Commercial Crew vehicles. The agency is also responsible for the Launch Services Program (LSP) which provides oversight of launch operations and countdown management for unmanned NASA launches. Most recently, NASA announced a new Space Launch System that it said would take the agency’s astronauts farther into space than ever before and lay the cornerstone for future human space exploration efforts by the U.S.

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble,
    Chandra, Spitzer ]and associated programs. NASA shares data with various national and international organizations such as from the Greenhouse Gases Observing Satellite.
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  • richardmitnick 9:16 pm on September 28, 2014 Permalink | Reply
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    From SPACE.com: ” NASA Exoplanet Mission to Hunt Down Earth-sized Worlds” 

    space-dot-com logo

    SPACE.com

    September 28, 2014
    Nola Taylor Redd

    Set to launch in 2017, NASA’s Transiting Exoplanet Survey Satellite (TESS) will monitor more than half a million stars over its two-year mission, with a focus on the smallest, brightest stellar objects.

    tess
    NASA/TESS

    During its observations, TESS is expected to find more than 3,000 new planets outside of our solar system, most of which will be possible for ground-based telescopes to observe.

    “Bright host stars are the best ones for follow-up studies of their exoplanets to pin down planet masses, and to characterize planet atmospheres,” said TESS principal investigator George Ricker, of the Massachusetts Institute of Technology’s Kavli Institute for Astrophysics, in an email.

    “TESS should be able to find over 200 Earths and super-Earths — defined as being twice the size of Earth,” said Peter Sullivan, a physics doctoral student at MIT. “Ten to 20 of those are habitable-zone planets.”

    Sullivan, who works with Ricker on TESS, led an analysis of the number of planets TESS would likely find based on the number and types of planets found by NASA’s Kepler mission. Kepler focused on a single region of the sky and studied all transiting planets within it. TESS, on the other hand, will examine almost the entire sky over its two-year mission, but capture only the brightest stars, many of which are expected to host terrestrial planets.

    NASA Kepler Telescope
    NASA/Kepler

    A bounty of Earth-sized extrasolar planets

    TESS will travel around Earth in a highly elliptical orbit that will range as distant as the moon. Along the way, it will use four cameras to observe a swatch of sky running from the celestial equator to the poles. TESS will observe each swatch for approximately a month before switching to the next region.

    Courtney Dressing, a doctoral student at the Harvard-Smithsonian Center for Astrophysics, compares the satellite’s observations to peeling an apple in vertical cuts that overlap near the stem. Because of the overlap, stars near the pole will be observed for more than 100 days, while stars near the equator will be observed for only 27 days.

    Dressing worked on a second model, based on Sullivan’s work, that predicts the number of planets near Earth that pass between the sun and their host star.

    “We predicted there should be about 100 transiting planets within 20 parsecs [about 65 light-years], and that roughly three of them should lie within the habitable zone of their host stars,” Dressing said.

    Not all of these planets will be detectable to the TESS mission. According to Dressing, the new telescope will be most sensitive to small planets orbiting stars 20 to 50 percent the size of our sun.

    Because TESS focuses on small, bright stars, it will be sensitive to Earth-sized planets and the massive terrestrial planets known as super-Earths. Like Kepler, TESS will measure the dip in light that occurs when a planet passes between its star and Earth, known as its transit. These dips will be larger and easier to spot for Earth-sized planets, which should dominate the population of small stars. Larger planets will also be visible, though they are expected to be less common around TESS’s targets.

    “A lot of Jupiter-sized planets have been detected from the ground, however, so we’re more excited about TESS finding small planets that can efficiently be found from space,” Sullivan said.

    A wealth of knowledge

    One of the most exciting things about the upcoming bonanza of planets TESS should find is the ability to study them with ground-based telescopes. Such observations will allow scientists to learn more about the planets, including characterizing their masses and studying their atmospheres.

    “Some of the planets detected by Kepler orbit stars that are too faint for ground-based follow-up observations,” Dressing said.

    Unable to study the planets from the ground, scientists cannot calculate their masses or understand more about the stars they orbit. By targeting bright stars, TESS seeks to overcome these challenges.

    “When observing bright stars, astronomers can use ground-based instruments to make very accurate measurements of the sizes, temperatures and masses of the stars hosting the planets,” Dressing said.

    TESS will also target stars ideal for NASA’s James Webb Space Telescope (JSWST) to observe. While TESS will make the initial brief detections, JWST will allow for the more detailed follow-up that will provide greater insights about the stars and their planets. The mission is expected to launch a little over a year after TESS, allowing for a wealth of potential targets.

    NASA Webb Telescope
    NASA/Webb

    “TESS will observe a portion of the sky for about 300 days,” Ricker said. “This special area is the ‘sweet spot’ for the JWST mission.”

    According to Sullivan’s model, TESS is expected to find between 10 and 20 Earths and super-Earths in the habitable zone of their stars. Sullivan’s simulation, which compared the changes in brightness of the expected number of transiting planets to a model of TESS’s sensitivity, used a broad definition of the habitable zone, where a planet would be capable of hosting water on its surface.

    “Under more strict habitable zone definitions, TESS would still find 5 to 10 small planets,” Sullivan said.

    To formally detect a planet, Sullivan said, TESS must observe two transits of a planet, which will enable scientists to locate the planet again and study it from the ground. The researchers won’t toss out single-detection sources, however. The most interesting may become targets for other telescopes.

    “TESS will find some interesting long-period planets with only one detection, but it will just take more resources to confirm these detections,” Sullivan said.

    This story was provided by Astrobiology Magazine, a web-based publication sponsored by the NASA astrobiology program.

    See the full article, with video, here.

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  • richardmitnick 3:12 pm on September 27, 2014 Permalink | Reply
    Tags: , Astrophysics, , ,   

    From NOVA: “It May Have Icy Clouds, But It’s Not a Planet, Not a Star, and Not in Our Solar System” 

    PBS NOVA

    NOVA

    Fri, 26 Sep 2014
    Joshua Sokol

    Brown dwarf W0855 was already special. A few times the size of Jupiter and super-cold, it’s halfway between a star and free-floating planet. Now ice clouds have been tentatively found in its atmosphere—which would mark the first time they’ve ever been seen on an extrasolar world.

    The solar system’s fourth-nearest companion doesn’t make it easy. It’s so faint that “I wanted to put on Rocky, do a Braveheart speech to the telescope operators,” said study author Jacqueline Faherty, who used the Las Campanas Observatory. in Chile [no hint of what telescope was used here]. She is the first astronomer to observe W0855 from the ground since it was found in data from NASA’s space-going Wide-Field Infrared Explorer (WISE) in April.

    Carnegie Las Campanas Observatory
    Las Campanas Observatory

    NASA Wise Telescope
    NASA/Wise

    w
    W0855, seen here in an artist’s conception, is a cold brown dwarf thought to have icy clouds in its soup of gases.

    Faherty’s work, which will be published in the Astrophysical Journal Letters, measured W0855’s brightness in different color bands. When compared with simulations of likely brown dwarf atmospheres, these data suggest W0855 boasts clouds of water ice and sulfide.

    On Earth, high-altitude cirrus clouds offer a point of comparison. Unlike cumulus clouds, which can contain both water vapor droplets and ice, cirrus clouds are composed of just ice crystals. Brown dwarf atmospheres are so cold and low-pressure that clouds there would form in much the same way, said astronomer Caroline Morley, whose published models were used by Faherty.

    Yet Morley and other astronomers unaffiliated with the study warn that this discovery is preliminary. “This tentative detection is made just with a few [brightness] points,” Morley wrote in an email. And Edward Wright, who studied W0855 with WISE, is skeptical that drawing conclusions from Morley’s models is the right idea. “The clouds depend on interpreting models which aren’t necessarily very good,” he said.

    It’s not that the presence of ice clouds would be shocking—just that they might not have been found yet. Kevin Luhman, who first discovered W0855, is also unconvinced. He wrote via email that, “there’s another set of cloudless models that she did not consider, and they actually agree well with her data.”

    According to these objectors, Faherty’s assumptions aren’t unreasonable. But her results depend on the brown dwarf having the same chemical blend as the Sun and on it being in chemical equilibrium—dependencies her paper also acknowledges.

    Regarding the cloud-free alternatives Luhman mentions, said Faherty, no “valid” models currently exist for comparison. Not only is the physics behind those other models unpublished, but the modelers themselves have lost confidence in their work, she said.

    All agree that NASA’s forthcoming James Webb Space Telescope will settle the question. The Webb’s coveted infrared sensitivity will let astronomers measure W0855’s whole spectrum, not just a few colors.

    For now, at least, Faherty is grateful even to find W0855 at new wavelengths and push the discussion forward. “It’s so faint that it’s at the limits, at the very hairy edge of what you can do from the ground,” she said. Her struggles with half-star, half-planet W0855 tease an even harder next step: understanding the atmospheres of planets orbiting faraway stars.

    See the full article here.

    NOVA is the highest rated science series on television and the most watched documentary series on public television. It is also one of television’s most acclaimed series, having won every major television award, most of them many times over.

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  • richardmitnick 6:37 am on September 27, 2014 Permalink | Reply
    Tags: , Astrophysics, , , Friends of Lick   

    Please help Embarrass The State if California University System into Saving the Lick Observatory 

    If you love Astronomy as I do, then you must help save the Lick Observatory. The University of California intends to defund this institution by 2018. We can not allow this to happen. We must embarrass the powers that be into keeping Lick, a very old institution alive and well.

    UCO Lick Observatory
    UCO Lick Observatory

    UCO Lick Shane TelescopeUCO Lick Shane Telescope interior
    Shane Telescope at Lick Observatory

    “Lick Observatory is the world’s first permanently occupied mountain-top observatory. The observatory, in a Classical Revival style structure, was constructed between 1876 and 1887, from a bequest from James Lick of $700,000 (approximately $22 million in 2014 US dollars). Lick, although primarily a carpenter and piano maker, chose the precise site atop Mount Hamilton and was there buried in 1887 under the future site of the telescope,[2] with a brass tablet bearing the inscription, “Here lies the body of James Lick.

    Lick additionally requested that Santa Clara County construct a “first-class road” to the summit, completed in 1876.[2] All of the construction materials had to be brought to the site by horse and mule-drawn wagons, which could not negotiate a steep grade. To keep the grade below 6.5%, the road had to take a very winding and sinuous path, which the modern-day road (California State Route 130) still follows. Tradition maintains that this road has exactly 365 turns (This is approximately correct, although uncertainty as to what should count as a turn makes precise verification impossible). Even those who do not normally suffer from motion-sickness find the road challenging[citation needed]. The road is closed when there is snow at Lick Observatory.[citation needed]

    The first telescope installed at the observatory was a 12-inch refractor made by Alvan Clark. Astronomer E. E. Barnard used the telescope to make “exquisite photographs of comets and nebulae,” according to D. J. Warner of Warner & Swasey Company.

    tel
    The Great Lick 91-centimeter (36-inch) refractor, in an 1889 engraving

    The 91-centimeter (36-inch) refracting telescope on Mt. Hamilton was Earth’s largest refracting telescope during the period from when it saw first light on January 3, 1888, until the construction of Yerkes Observatory in 1897. Warner & Swasey designed and built the telescope mounting, with the 91-centimeter (36-inch) lens manufactured by one of the Clark sons, Alvan Graham. E. E. Barnard used the telescope in 1892 to discover a fifth moon of Jupiter. This was the first addition to Jupiter’s known moons since Galileo observed the planet through his parchment tube and spectacle lens. The telescope provided spectra for W. W. Campbell’s work on the radial velocities of stars.

    In 1950, the California state legislature appropriated funds for a 300-centimeter (120-inch)reflector telescope, which was completed in 1959. The observatory additionally has a 61-centimeter (24-inch) Cassegrain reflector dedicated to photoelectric measurements of star brightness, and received a pair of 51-centimeter (20-inch) astrographs from the Carnegie Corporation.[2]

    In May 1888, the observatory was turned over to the Regents of the University of California.”

    Now, with Keck and the coming TMT, The University of California will defund Lick by 2018. We must not allow this to happen. Please visit “Friends of Lick” and be one of many to make a small donation to help save Lick and embarrass The University of California into keeping Lick alive and well.

    Lick is one of the few places in the world where a child can actually touch and use a telescope. Please additionally send an email expressing your interest in not seeing Lick die of neglect.

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