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  • richardmitnick 7:29 am on September 13, 2017 Permalink | Reply
    Tags: , , , , , Does organic material in comets predate our solar system?, EarthSky,   

    From EarthSky: “Does organic material in comets predate our solar system?” 



    September 13, 2017
    Deborah Byrd

    “If cometary organic molecules were indeed produced in interstellar space—and if they played a role in the emergence of life on our planet—might they not also have seeded life on many other planets of our galaxy?”

    Comet 67P/Churyumov-Gerasimenko as seen by ESA’s Rosetta spacecraft.

    On September 4, 2017, researchers in Paris announced the results of their study of the organic compounds – combinations of carbon, hydrogen, nitrogen, and oxygen – in comet 67P Churyumov-Gerasimenko. This is the comet studied up-close and in detail by ESA’s Rosetta spacecraft for two years, beginning in August 2014.

    ESA/Rosetta spacecraft

    The sorts of organic molecules found in this comet and others have long been proposed by scientists as possible building blocks for life on Earth. Published in late August in the peer-reviewed journal Monthly Notices of the Royal Astronomical Society, the French researchers advance the theory that this organic matter has its origin in interstellar space and predates the birth of our solar system.

    The Rosetta mission found a large amount of organic material in the nucleus of the comet, which some people simply 67P and others call Chury for Klim Ivanovich Churyumov, one of its discovers. The Rosetta mission found that organic matter made up 40% (by mass) of the nucleus of the comet. According to researchers Jean-Loup Bertaux and Rosine Lallement, not only were the organic molecules were produced in interstellar space, well before the formation of the solar system, but also other astronomers are already very familiar with the source of this matter. Their statement explained:

    “For 70 years, scientists have known that analysis of stellar spectra indicates unknown absorptions, throughout interstellar space, at specific wavelengths called the diffuse interstellar bands (DIBs). DIBs are attributed to complex organic molecules that American astrophysicist Theodore Snow believes may constitute the largest known reservoir of organic matter in the universe.

    This interstellar organic material is usually found in the same proportions. However, very dense clouds of matter like presolar nebulae are exceptions. In the middle of these nebulae, where matter is even denser, DIB absorptions plateau or even drop. This is because the organic molecules responsible for DIBs clump together there. The clumped matter absorbs less radiation than when it floated freely in space.

    Such primitive nebulae end up contracting to form a solar system like our own, with planets . . . and comets. The Rosetta mission taught us that comet nuclei form by gentle accretion of grains progressively greater in size. First, small particles stick together to form larger grains. These in turn combine to form still larger chunks, and so on, until we have a comet nucleus a few kilometers wide.

    Thus, the organic molecules that formerly populated the primitive nebulae—and that are responsible for DIBs—were probably not destroyed, but instead incorporated into the grains making up cometary nuclei. And there they have remained for 4.6 billion years. A sample-return mission would allow laboratory analysis of cometary organic material and finally reveal the identity of the mysterious interstellar matter underlying observed patterns in stellar spectra.

    If cometary organic molecules were indeed produced in interstellar space—and if they played a role in the emergence of life on our planet, as scientists believe today—might they not also have seeded life on many other planets of our galaxy?”

    Bottom line: French researchers advance the theory that the organic matter found in comets – possible building blocks for earthly life – has its origin in interstellar space and predates the birth of our solar system.

    See the full article here .

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  • richardmitnick 8:25 am on September 11, 2017 Permalink | Reply
    Tags: 2014 MU69 will soon become the only Kuiper Belt object ever to be visited by a spacecraft, , , , , EarthSky, , Pluto craft wakes from hibernation today   

    From EarthSky: “Pluto craft wakes from hibernation today” 



    September 11, 2017
    Deborah Byrd

    NASA/New Horizons spacecraft

    And last week mission scientists filed a flight plan for New Horizons’ next flyby – of the Kuiper Belt object 2014 MU69 – in early 2019. It’ll be farthest encounter yet between an earthly spacecraft and distant solar system body.

    This image shows New Horizons’ current position along its full planned trajectory. The green segment of the line shows where New Horizons has traveled since launch; the red indicates the spacecraft’s future path. Positions of stars with magnitude 12 or brighter are shown from this perspective, which is slightly above the orbital plane of the planets. Via Johns Hopkins’ page Where is New Horizons?

    NASA’s New Horizons spacecraft – which visited Pluto in July, 2015 – was placed in hibernation on April 7, 2017. The craft is set to be awoken today (September 11, 2017). In the meantime, the science and mission operations teams have been developing detailed command loads for New Horizon’s next encounter, a nine-day flyby of the Kuiper Belt object 2014 MU69 on New Year’s Day, 2019. Among other things, the mission has now set the flight plan and the distance for closest approach, aiming to come three times closer to MU69 than it famously flew past Pluto in 2015.

    Hibernation reduced wear and tear on the spacecraft’s electronics, lowered operations costs and freed up NASA Deep Space Network tracking and communication resources for other missions. But New Horizons mission activity didn’t entirely stop during the hibernation period. While much of the craft is unpowered during hibernation, the onboard flight computer has continued to monitor system health and to broadcast a weekly beacon-status tone back to Earth. About once a month, the craft has sent home data on spacecraft health and safety. Onboard sequences sent in advance by mission controllers will eventually wake New Horizons to check out critical systems, gather new Kuiper Belt science data, and perform any necessary course corrections.

    2014 MU69 will soon become the only Kuiper Belt object ever to be visited by a spacecraft. It’ll be the farthest planetary encounter in history – some one billion miles (1.5 billion km) beyond Pluto and more than four billion miles (6.5 billion km) from Earth. If all goes as planned, New Horizons will come to within just 2,175 miles (3,500 km) of MU69 at closest approach, peering down on it from celestial north. The alternate plan, to be employed in certain contingency situations such as the discovery of debris near MU69, would take New Horizons within 6,000 miles (10,000 km)— still closer than the 7,800-mile (12,500-km) flyby distance to Pluto.

    The Johns Hopkins Applied Physics Laboratory manages the New Horizons mission for NASA’s Science Mission Directorate. Alan Stern, of the Southwest Research Institute (SwRI) is the principal investigator and leads the mission; SwRI leads the science team, payload operations, and encounter science planning. New Horizons is part of the New Frontiers Program managed by NASA’s Marshall Space Flight Center in Huntsville, Alabama. APL designed, built and operates the New Horizons spacecraft. NASA.

    The Sleeping Spacecraft: How Hibernation Worked

    During hibernation mode, much of the New Horizons spacecraft was unpowered. The onboard flight computer monitored system health and broadcast a weekly beacon-status tone back to Earth. Onboard sequences sent in advance by mission controllers woke New Horizons two or three times each year to check out critical systems, calibrate instruments, gather some science data, rehearse Pluto-encounter activities, and perform course corrections.

    New Horizons pioneered routine cruise-flight hibernation for NASA. Not only has hibernation reduced wear and tear on the spacecraft’s electronics, it also lowered operations costs and freed up NASA Deep Space Network tracking and communication resources for other missions.

    Bottom line: The New Horizons spacecraft – famous for visiting Pluto in 2015 – will wake from a 157-day hibernation on September 11, 2017. Mission controllers have filed a flight plan for the 2019 encounter with 2014 MU69

    See the full article here .

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  • richardmitnick 9:01 am on September 4, 2017 Permalink | Reply
    Tags: A new look at ocean worlds, , , , , EarthSky, Europa and Enceladus - Ocean worlds?,   

    From EarthSky: “A new look at ocean worlds” 



    September 4, 2017
    Paul Scott Anderson

    Here’s how the James Webb Space Telescope – successor to Hubble, due to launch in 2018 – will study Jupiter’s moon Europa and Saturn’s moon Enceladus.

    NASA/ESA/CSA Webb Telescope annotated

    This is Saturn’s moon Enceladus, as seen by the Cassini spacecraft. It’s thought to have a subsurface ocean and can be seen spewing water vapor from its interior. Photo via NASA/JPL-Caltech.

    NASA’s upcoming James Webb Space Telescope (JWST) will be used to study two of the most fascinating moons in our solar system – Europa and Enceladus, also known as ocean worlds since both have global oceans of water beneath their outer icy surfaces. The new observations will help scientists learn more about conditions on these worlds and guide the development of future robotic missions.

    Both moons are exciting targets since Europa’s surface has deposits of minerals thought to have come up from the ocean below, and Enceladus has huge plumes of water vapor erupting through fissures in the icy surface, originating from the subsurface ocean. Europa may also have plumes, which have been tentatively identified but not confirmed yet. Enceladus’ plumes also contain organic compounds of various complexities, which were sampled directly by the Cassini spacecraft multiple times.

    A Galileo orbiter image of Europa has been added to a just-released Hubble Space Telescope image of what might be towering geysers of water erupting from near the moon’s south pole. NASA / ESA / W. Sparks / USGS Astrogeology Science Center

    Enceladus. NASA.

    Astronomer Heidi Hammel is executive vice president of the Association of Universities for Research in Astronomy (AURA). She is spearheading the effort to study our solar system with the Webb telescope. She said:

    “We chose these two moons because of their potential to exhibit chemical signatures of astrobiological interest.”

    Astronomers will use Webb’s near-infrared camera (NIRCam) to take high-resolution images of Europa’s surface, to search for hot regions related to plumes and active geological processes. If a plume is found, they can then use Webb’s near-infrared spectrograph (NIRSpec) and mid-infrared instrument (MIRI) to analyze the plume’s composition. This video below shows possible results of using spectroscopy on Europa’s water plumes, obtainable using the Webb telescope’s NIRSpec instrument.

    NASA Webb NIRCam

    NASA Webb NIRspec

    NASA Webb MIRI

    Geronimo Villanueva, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is the lead scientist on the Webb telescope’s observation of Europa and Enceladus. He said:

    “Are they made of water ice? Is hot water vapor being released? What is the temperature of the active regions and the emitted water? Webb telescope’s measurements will allow us to address these questions with unprecedented accuracy and precision.”

    JWST will be able to study Enceladus’ plumes and surface in a similar manner, even though it is about 10 times smaller than Europa as seen by the telescope.

    For both moons, a focus will be to search for organic signatures such as methane, methanol, and ethane in the plumes. Evidence of life itself, like microbes, would be more difficult since some life-like processes could also have a geological explanation. Villanueva noted:

    “We only expect detections if the plumes are particularly active and if they are organic-rich.”

    JWST is the successor to the Hubble Space Telescope (HST) and will be the most powerful space-based telescope ever built. It is an international project led by NASA, along with the European Space Agency (ESA) and the Canadian Space Agency (CSA).

    Even if JWST isn’t able to find signs of life on either moon, it will be another huge step in understanding what conditions are like, both on their surfaces and below the ice in the oceans themselves, building on results from spacecraft such as Galileo and Cassini. It will help prepare the way for future, more advanced probes on the drawing boards now which may be able to answer that question of whether life has ever existed on (in) these far-off ocean worlds.

    Diagram of an interior cross-section of the crust of Enceladus, showing how hydrothermal activity is thought to be causing the plumes of water vapor on the surface. Image via NASA-GSFC/SVS/NASA/JPL-Caltech/Southwest Research Institute.

    Bottom line: The James Webb Space Telescope will be used in part to study our own solar system, for example, Jupiter’s moon Europa and Saturn’s moon Enceladus, both considered ocean worlds.

    See the full article here .

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  • richardmitnick 12:17 pm on August 21, 2017 Permalink | Reply
    Tags: , , , , EarthSky, , ,   

    From EarthSky: “Studying sun’s atmosphere on eclipse day” 



    August 17, 2017
    EarthSky Voices

    Monday’s total solar eclipse will give scientists a rare opportunity to study the lower regions of the sun’s corona. Here’s what NASA scientists will be investigating.

    A total solar eclipse gives scientists a rare opportunity to study the lower regions of the sun’s corona. These observations can help us understand solar activity, as well as the unexpectedly high temperatures in the corona. Image via NASA/S. Habbal, M. Druckmüller and P. Aniol.

    By Sarah Frazier, NASA’s Goddard Space Flight Center

    A total solar eclipse happens somewhere on Earth about once every 18 months. But because Earth’s surface is mostly ocean, most eclipses are visible over land for only a short time, if at all. The total solar eclipse of August 21, 2017, is different – its path stretches over land for nearly 90 minutes, giving scientists an unprecedented opportunity to make scientific measurements from the ground.

    Total solar eclipse of August 21, 2017: All you need to know

    When the moon moves in front of the sun on August 21, it will completely obscure the sun’s bright face. This happens because of a celestial coincidence – though the sun is about 400 times wider than the moon, the moon on August 21 will be about 400 times closer to us, making their apparent size in the sky almost equal. In fact, the moon will appear slightly larger than the sun to us, allowing it to totally obscure the sun for more than two and a half minutes in some locations. If they had the exact same apparent size, the total eclipse would only last for an instant.

    The eclipse will reveal the sun’s outer atmosphere, called the corona, which is otherwise too dim to see next to the bright sun. Though we study the corona from space with instruments called coronagraphs – which create artificial eclipses by using a metal disk to block out the sun’s face – there are still some lower regions of the sun’s atmosphere that are only visible during total solar eclipses. Because of a property of light called diffraction, the disk of a coronagraph must block out both the sun’s surface and a large part of the corona in order to get crisp pictures. But because the moon is so far away from Earth – about 230,000 miles away during the eclipse – diffraction isn’t an issue, and scientists are able to measure the lower corona in fine detail.

    NASA is taking advantage of the August 21, 2017, eclipse by funding 11 ground-based science investigations across the United States. Six of these focus on the sun’s corona.

    The source of space weather

    Our sun is an active star that constantly releases a flow of charged particles and magnetic fields known as the solar wind. This solar wind, along with discrete burps of solar material known as coronal mass ejections, can influence Earth’s magnetic field, send particles raining down into our atmosphere, and – when intense – impact satellites. Though we’re able to track these solar eruptions when they leave the sun, the key to predicting when they’ll happen could lie in studying their origins in the magnetic energy stored in the lower corona.

    A team led by Philip Judge of the High Altitude Observatory in Boulder, Colorado, will use new instruments to study the magnetic field structure of the corona by imaging this atmospheric layer during the eclipse. The instruments will image the corona to see fingerprints left by the magnetic field in visible and near-infrared wavelengths from a mountaintop near Casper, Wyoming. One instrument, POLARCAM, uses new technology based on the eyes of the mantis shrimp to obtain novel polarization measurements, and will serve as a proof-of-concept for use in future space missions. The research will enhance our understanding of how the sun generates space weather. Judge said:

    “We want to compare between the infrared data we’re capturing and the ultraviolet data recorded by NASA’s Solar Dynamics Observatory and JAXA/NASA’s Hinode satellite.


    JAXA/HINODE spacecraft

    This work will confirm or refute our understanding of how light across the entire spectrum forms in the corona, perhaps helping to resolve some nagging disagreements.”

    The results from the camera will complement data from an airborne study imaging the corona in the infrared, as well as another ground-based infrared study led by Paul Bryans at the High Altitude Observatory.

    High Altitude Observatory. Hawaii location.

    Bryans and his team will sit inside a trailer atop Casper Mountain in Wyoming, and point a specialized instrument at the eclipse. The instrument is a spectrometer, which collects light from the sun and separates each wavelength of light, measuring their intensity. This particular spectrometer, called the NCAR Airborne Interferometer, will, for the first time, survey infrared light emitted by the solar corona. Bryant said:

    “These studies are complementary. We will have the spectral information, which reveals the component wavelengths of light. And Philip Judge’s team will have the spatial resolution to tell where certain features are coming from.”

    This novel data will help scientists characterize the corona’s complex magnetic field — crucial information for understanding and eventually helping to forecast space weather events. The scientists will augment their study by analyzing their results alongside corresponding space-based observations from other instruments aboard NASA’s Solar Dynamics Observatory and the joint NASA/JAXA Hinode.

    In Madras, Oregon, a team of NASA scientists led by Nat Gopalswamy at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, will point a new, specialized polarization camera at the sun’s faint outer atmosphere, the corona, taking several-second exposures at four selected wavelengths in just over two minutes. Their images will capture data on the temperature and speed of solar material in the corona. Currently these measurements can only be obtained from Earth-based observations during a total solar eclipse.

    To study the corona at times and locations outside a total eclipse, scientists use coronagraphs, which mimic eclipses by using solid disks to block the sun’s face much the way the moon’s shadow does. Typical coronagraphs use a polarizer filter in a mechanism that turns through three angles, one after the other, for each wavelength filter. The new camera is designed to eliminate this clunky, time-consuming process, by incorporating thousands of tiny polarization filters to read light polarized in different directions simultaneously. Testing this instrument is a crucial step toward improving coronagraphs and ultimately, our understanding of the corona — the very root of the solar radiation that fills up Earth’s space environment.

    NASA’s Solar and Heliospheric Observatory, or SOHO, constantly observes the outer regions of the sun’s corona. During the Aug. 21, 2017, eclipse, scientists will observe the lower regions of the sun’s corona to better understand the source of solar explosions called coronal mass ejections, as well as the unexpectedly high temperatures in the corona. Image via ESA/NASA/SOHO.


    Unexplained coronal heating

    The answer to another mystery also lies in the lower corona: It is thought to hold the secrets to a longstanding question of how the solar atmosphere reaches such unexpectedly high temperatures. The sun’s corona is much hotter than its surface, which is counterintuitive, as the sun’s energy is generated by nuclear fusion at its core. Usually temperatures go down consistently as you move away from that heat source, the same way that it gets cooler as you move away from a fire – but not so in the case of the sun’s atmosphere. Scientists suspect that detailed measurements of the way particles move in the lower corona could help them uncover the mechanism that produces this enormous heating.

    Padma Yanamandra-Fisher of the Space Science Institute will lead an experiment to take images of the lower corona in polarized light. Polarized light is when all the light waves are oriented the same way, and it is produced when ordinary, unpolarized light passes through a medium – in this case, the electrons of the inner solar corona. Yanamandra-Fisher said:

    “By measuring the polarized brightness of the inner solar corona and using numerical modeling, we can extract the number of electrons along the line of sight. Essentially, we’re mapping the distribution of free electrons in the inner solar corona.”

    Mapping the inner corona in polarized light to reveal the density of elections is a critical factor in modeling coronal waves, one possible source of coronal heating. Along with unpolarized light images collected by the NASA-funded citizen science project called Citizen CATE, which will gather eclipse imagery from across the country, these polarized light measurements could help scientists address the question of the solar corona’s unusually high temperatures.

    Shadia Habbal of the University of Hawaii’s Institute for Astronomy in Honolulu will lead a team of scientists to image the sun during the total solar eclipse. The eclipse’s long path over land allows the team to image the sun from five sites across four different states, about 600 miles apart, allowing them to track short-term changes in the corona and increasing the odds of good weather.

    They will use spectrometers, which analyze the light emitted from different ionized elements in the corona. The scientists will also use unique filters to selectively image the corona in certain colors, which allows them to directly probe into the physics of the sun’s outer atmosphere.

    With this data, they can explore the composition and temperature of the corona, and measure the speed of particles flowing out from the sun. Different colors correspond to different elements — nickel, iron and argon — that have lost electrons, or been ionized, in the corona’s extreme heat, and each element ionizes at a specific temperature. By analyzing such information together, the scientists hope to better understand the processes that heat the corona.

    Amir Caspi of the Southwest Research Institute in Boulder, Colorado, and his team will use two of NASA’s WB-57F research jets take observations from twin telescopes mounted on the noses of the planes. They will ­­­­­capture the clearest images of the sun’s outer atmosphere — the corona — to date and the first-ever thermal images of Mercury, revealing how temperature varies across the planet’s surface.

    Bottom line: NASA scientists will study the sun’s atmosphere at the total solar eclipse of August 21, 2017. [Alot!!]

    See the full article here .

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  • richardmitnick 11:05 am on August 15, 2017 Permalink | Reply
    Tags: , , , , Dark Rift in the Milky Way, EarthSky   

    From EarthSky: “Dark Rift in the Milky Way” 



    August 14, 2017
    Bruce McClure

    Thick dust clouds block our night-time view of the Milky Way, creating what is sometimes called the Great Rift or Dark Rift. Image via NASA.

    Have you ever looked up from a dark place on a starry August evening and noticed the dark areas in the Milky Way? For centuries, skywatchers pondered this Great Rift or Dark Rift, as it’s called, but today’s astronomers know it consists of dark, obscuring dusk in the disk of our Milky Way galaxy.

    How to see the Dark Rift. The Milky Way is easy to see if you have dark skies. It’s a shining band, stretching across the sky. If you want to see the Dark Rift, that’s easy, too, as long as you realize you aren’t looking for a bright object. You’re looking instead for dark lanes of dust, running the length of the starlit Milky Way band.

    You will be looking south from sometime in June or July (probably) through about October – in a dark sky – and, from a Northern Hemisphere location, you’ll see the Milky Way come off the southern to southwestern horizon. Notice that the Milky Way band looks milky white. The skies aren’t really black like ink between stars in the Milky Way. You will know when you see the Dark Rift because it is as if someone took a marker and colored it darker.

    Photo by Manish Mamtani.

    Don’t miss the Milky Way and Great Rift rise. One of the most spectacular sights is to see the Milky Way as it rises. Around 10 p.m. in June, or earlier in July and August, step outside and look in the east to see the phenomena of the Great Rift and the rest of the Milky Way make its dramatic entrance as it rises into the night skies.

    Make sure you have your binoculars handy to scan the Milky Way. There are many interesting star forming regions, star clusters and millions of stars that will capture your attention.

    Look in the Great Rift and imagine all the stars that will eventually reveal themselves as the molecular gas dissipates. More about that below.

    Molecular dust is the reason it is dark. Stars are formed from great clouds of gas and dust in our Milky Way galaxy and other galaxies. When we look up at the starry band of the Milky Way, and see the Dark Rift, we are looking into our galaxy’s star-forming regions. The protostars (newly forming stars) are generating molecular dust that doesn’t allow light in the visual spectrum to shine through.

    However, with the advancement of telescopes that see in different light waves – such as X-rays or infrared – we now know that there’s activity in the area.

    Ancient cultures focused on the dark not the light areas. You know those paintings where if you look at the light areas you see one thing, but in the dark areas you see something else?

    The Dark Rift is a bit like that. A few ancient cultures in Central and South America saw the dark areas of the Milky Way as constellations. These dark constellations had a variety of myths associated with them. For example, one important dark constellation was Yacana the Llama. It rises above Cuzco, the ancient city of the Incas, every year in November.

    By the way, the other famous area of the sky that is obscured by molecular dust is visible from the Southern Hemisphere. It’s the famous Coalsack Nebula near the Southern Cross, also known as the constellation Crux. The Coal Sack is another region of star-forming activity in our night sky – much like the Great Rift.

    Bottom line: On a dark August night, looking edgewise into our galaxy’s disk, you’ll notice a long, dark lane dividing the bright starry band of the Milky Way. This Dark Rift is a place where new stars are forming.

    See the full article here .

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  • richardmitnick 1:25 pm on August 5, 2017 Permalink | Reply
    Tags: Albireo-Doubke (tripple) star system, , , , , EarthSky   

    From EarthSky: “Star of the week: Albireo” 



    Albireo – one star blue and the other golden – as captured by EarthSky community member Tom Wildoner in July, 2015. Visit Tom’s blog, Leisurely Scientist.

    Albireo – also called Beta Cygni – isn’t the brightest star in the sky. It looks like an ordinary single star to the eye. But peer at it through a telescope, you’ll learn why stargazers love Albireo. With a telescope, you’ll easily see Albireo as a beautiful double star, with the brighter star gold and the dimmer star blue.

    How can you see Albireo as two stars? They are best viewed at 30X (“30 power” or a magnification of 30). Unless you have exceedingly powerful binoculars, mounted on a tripod, binoculars won’t show you Albireo as two stars, but any small telescope will. When you do see Albireo as two stars, notice the striking color contrast between the two.

    How can you spot Albireo in the night sky? It’s easy to find, if you can located Cygnus the Swan. Cygnus has an easy-to-recognize shape, that of a cross, and the constellation is also known as the Northern Cross. The brightest star in Cygnus, called Deneb, marks the head of the Cross or the Tail of the Swan. Albireo marks the base of the Cross or the Head of Cygnus.

    The constellation Cygnus the Swan. The bright star Deneb is in the Tail of Cygnus, while Albireo is at the Head of the Swan. Albireo represents the Swan’s Beak or Eye. Image via Constellation of Words.

    The constellation Cygnus lies within a larger star pattern known as the Summer Triangle. See the three bright stars here: Vega, Deneb and Altair? See how the pattern of the cross (Cygnus the Swan) likes inside the triangle made by those three stars? More about the Summer Triangle here.

    The two stars of Albireo constitute a true binary star system. In other words, its two stars aren’t merely a chance alignment as seen from Earth. Instead, they revolve around a common center of mass.

    These two stars lie quite far apart, however, and might take as long as 100,000 years to orbit one another. Even though these two stars appear close together in a telescope, keep in mind that you’re looking at a system that’s 430 light-years away.

    By the way, the brighter of the two stars in the Albireo system has been found with advanced telescopic techniques to be two stars as well. Thus there are at least three stars in this system.

    Bottom line: The star Albireo in the constellation Cygnus – also known as Beta Cygni – is a famous double star. A small telescope reveals that one star is blue and the other is gold.

    See the full article here .

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  • richardmitnick 1:34 pm on July 28, 2017 Permalink | Reply
    Tags: , EarthSky, Gravitational anomaly seen in lab crystal, , ,   

    From EarthSky: “Gravitational anomaly seen in lab crystal” 



    July 24, 2017
    Daniela Breitman

    An exotic effect in particle physics, theorized to occur in immense gravitational fields — near a black hole, or in conditions just after the Big Bang — has been seen in laboratory crystal.

    Scientists use laboratory crystal to see how spacetime curvature affects subatomic particles known as Weyl fermions. Image by Robert Strasser, Kees Scherer, collage by Michael Buker via Nature.

    Physicist Johannes Gooth and his team from IBM Research in Zurich, Switzerland, claim to have observed an effect called an axial–gravitational anomaly in a crystal. The effect is predicted by Einstein’s General Relativity, which describes gravity as curved spacetime. The newly observed laboratory effect was thought to be observable only under conditions of immense gravity — for example, near a black hole, or shortly after the Big Bang. Yet it has been seen in a lab. The scientists published their work in the peer-reviewed journal Nature on July 20, 2017.

    What is a gravitational anomaly? A good explanation comes from co-author Karl Landsteiner at the IBM Research Blog:

    “Symmetries are the holy grail for physicists. Symmetry means that one can transform an object in a certain way that leaves it invariant. For example, a round ball can be rotated by an arbitrary angle, but always looks the same. Physicists say it is ‘symmetric under rotations.’ Once the symmetry of a physical system is identified it’s often possible to predict its dynamics.

    Sometimes however the laws of quantum mechanics destroy a symmetry that would happily exist in a world without quantum mechanics, i.e classical systems. Even to physicists this looks so strange that they named this phenomenon an ‘anomaly.’

    For most of their history, these quantum anomalies were confined to the world of elementary particle physics explored in huge accelerator laboratories such as Large Hadron Collider at CERN in Switzerland …

    But now a quantum anomaly has been observed in a lab. Nature said the result bolsters an emerging view that crystals such as these — crystals whose properties are dominated by quantum-mechanical effects – can act as experimental test-beds for physics effects that could be seen otherwise only under exotic circumstances (Big Bang, black hole, particle accelerator).

    Co-author of the new paper Karl Landsteiner, a string theorist at the Instituto de Fisica Teorica UAM/CSIC, made this graphic to explain the gravitational anomaly. Image via http://newatlas.com/gravitational-anomaly-observed/50559/.

    In advanced science classes, at one point or another, we are taught Lavoisier’s Law. It states that nothing is being created, nothing is being lost, and that all is being transformed. This law – the law of the conservation of mass – is an underlying principle of basic science.

    However, when peek into the funky world of quantum materials through high energy physics, the law of the conservation of mass seems to break apart.

    Meanwhile, Einstein’s famous equation, E=mc^2, suggests that mass and energy are interchangeable (E, or energy, equals m, or mass, times c^2, or the speed of light squared).

    Gooth and his team used Einstein’s equation to create an analogy: a change heat (E) is the same as a change in mass (m). In other words, changing the temperature of a Weyl semimetal would be the same as generating a gravitational field.

    Lead author of the paper, Johannes Gooth, explained:

    “For the first time, we have experimentally observed this quantum anomaly on Earth which is extremely important towards our understanding of the universe.”

    Co-authors of the paper (left to right): Fabian Menges, Johannes Gooth, and Bernd Gotsmann in a noise-free lab at IBM Research, Zurich. Image via <a href="https://c1.staticflickr.com/5/4206/34582536554_4fff0cdf49.jpg.

    Weyl fermions have been proposed in the 1920s by mathematician Hermann Weyl. They have been very interesting to scientists for some time, for some of their unique properties.

    This discovery is considered a spectacular one by many scientists, but not all scientists are convinced. Boris Spivak, physicist at the University of Washington in Seattle, doesn’t believe that an axial-gravitational anomaly could be observed in a Weyl semimetal. He said:

    "There are many other mechanisms which can explain their data."

    As always in science, time will tell.

    Bottom line: IBM scientists claim to have observed the effects of the axial-gravitational anomaly in a laboratory crystal.

    See the full article here .

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  • richardmitnick 11:18 am on July 16, 2017 Permalink | Reply
    Tags: , , , Citizen Science helps process images, , EarthSky,   

    From EarthSky: “Wow! Juno’s super-close Red Spot images” Do Not Pass This Up 



    July 12, 2017
    Deborah Byrd

    Raw images from the Juno spacecraft’s extremely close sweep past Jupiter’s Red Spot are beginning to come in. NASA invites you to help process them!

    One of the first processed raw map-projected images of Jupiter’s Great Red Spot from Juno’s July 10 flyover, via Jason Major (@JPMajor on Twitter).

    Earlier than expected, the close-ups of Jupiter’s Great Red Spot – made possible by a close sweep past the planet by the Juno spacecraft on July 10 – are beginning to arrive! NASA had said originally not to expect them until July 14, but they started arriving on the 12th! What’s more, NASA has invited “citizen scientists” to help process the images, saying on the JunoCam online database page:

    “This is where we will post raw images. We invite you to download them, do your own image processing, and we encourage you to upload your creations for us to enjoy and share. The types of image processing we’d love to see range from simply cropping an image to highlighting a particular atmospheric feature, as well as adding your own color enhancements, creating collages and adding advanced color reconstruction.”

    The citizen-scientist images, as well as the raw images they used for image processing, can be found at:


    Juno, which began orbiting the giant planet on July 4, 2016, came closer to Jupiter last weekend than any spacecraft ever has. In what scientist call Perijove 7 (a perijove is the spacecraft’s closest point in orbit to Jupiter’s center), Juno came as little as 2,200 miles (3,500 km) above Jupiter’s cloudtops. The probe was slightly higher when it was directly over the Great Red Spot (5,600 miles, or 9,000 km), but, still … awesome images ahead as the processing progresses.

    For now, enjoy these early images!

    Here’s a processed Juno image from Jon M. Greif, who wrote: “The Great Red Spot, a huge storm, the size of 2-3 Earth diameters, that has been raging on the surface of Jupiter for as long as people have studied the planet.”

    This enhanced-color image of Jupiter’s Great Red Spot was created by citizen scientist Gerald Eichstädt using data from the JunoCam imager on NASA’s Juno spacecraft. Image via NASA/ JPL-Caltech/ SwRI/ MSSS/ Gerald Eichstädt.

    Jupiter at Perijove 7, via NASA/ JPL-Caltech/ MSSS/ SwRI/ Kevin M. Gill.

    Bottom line: Raw images from Juno’s July 10 extremely close sweep past Jupiter’s Red Spot are beginning to come in. NASA invites you to help process them!

    See the full article here .

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  • richardmitnick 12:36 pm on July 7, 2017 Permalink | Reply
    Tags: , , , , EarthSky, How do planets form after star death?   

    From EarthSky: “How do planets form after star death?” 



    Astronomers studied the Geminga pulsar (inside the black circle), seen here moving towards the upper left. The orange dashed arc and cylinder show a ‘bow-wave’ and a ‘wake’ which might be key to after-death planet formation. The region shown is 1.3 light-years across. Image via Jane Greaves / JCMT / EAO/ RAS.

    The Royal Astronomical Society’s National Astronomy Meeting is going on this week (July 2-6, 2017) in Yorkshire, England. One interesting presentation comes from astronomers Jane Greaves and Wayne Holland, who believe they’ve found an answer to the 25-year-old mystery of how planets form around neutron stars, essentially dead stars left behind by supernova explosions. These astronomers studied the Geminga pulsar, thought to be a neutron star left by a supernova some 300,000 years ago. This object is known to be moving incredibly fast through our galaxy, and the astronomers have observed a bow-wave, shown in the image above, that might be crucial to forming after-death planets.

    They looked at the extreme environment around a neutron star – the sort of star we typically observe as a pulsar – a super-dense star remnant, left behind by a supernova.

    The first-ever confirmed detection of extrasolar planets – or planets orbiting distant suns – came in 1992, when astronomers found several terrestrial-mass planets orbiting the pulsar PSR B1257+12. Since then they’ve learned that planets orbiting neutron stars are incredibly rare; at least, few have been found.

    The two scientists observed Geminga using the James Clerk Maxwell Telescope (JCMT) near the summit of Mauna Kea in Hawaii.

    East Asia Observatory James Clerk Maxwell telescope, Mauna Kea, Hawaii, USA

    The light the astronomers detected has a wavelength of about half a millimeter, is invisible to the human eye, and struggles to get through the Earth’s atmosphere. They used a special camera system called SCUBA and said:

    What we saw was very faint. To be sure, we went back to it in 2013 with the new camera our Edinburgh-based team had built, SCUBA-2, which we also put on JCMT. Combining the two sets of data helped to ensure we weren’t just seeing some faint artifacts.

    If ALMA data confirm their new model for Geminga, the team hopes to explore some similar pulsar systems, and contribute to testing ideas of planet formation by seeing it happen in exotic environments. Their statement said:

    This will add weight to the idea that planet birth is commonplace in the universe.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    See the full article here .

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  • richardmitnick 11:21 am on July 2, 2017 Permalink | Reply
    Tags: , , , , , EarthSky   

    From EarthSky: “The enduring mystique of Barnard’s Star” 



    June 27, 2017
    Larry Sessions

    Our sun’s closest neighbors among the stars, including Barnard’s Star. Image via NASA PhotoJournal.

    Perhaps you know that, over the scale of our human lifespans, the stars appear fixed relative to one another. But Barnard’s Star – sometimes called Barnard’s Runaway Star – holds a speed record of sorts as the fastest-moving star in Earth’s skies. It moves fast with respect to other stars because it’s relatively close, only about 6 light-years away. What does its fast motion mean? It means Barnard’s Star is nearby! It’s only about six light-years away. Relative to other stars, Barnard’s Star moves 10.3 arcseconds per year, or about the width of a full moon in 174 years. This might not seem like much. But – to astronomers – Barnard’s Star is virtually zipping across the sky. Follow the links below to learn more about Barnard’s Star, which has high interest for astronomers and the public alike.

    Barnard’s Star in history and popular culture

    How to see Barnard’s Star

    The science of Barnard’s Star

    Barnard’s star, 1985 to 2005. Most stars are fixed with respect to each other, but – being close to us – Barnard’s Star appears to move. Image via Steve Quirk/ Wikimedia Commons.

    Barnard’s Star in history and popular culture Yerkes Observatory astronomer E. E. Barnard discovered the large proper motion of Barnard’s Star – that is, motion across our line of sight – in 1916.

    He noticed it while comparing photographs of the same part of the sky taken in 1894 and again in 1916. The star appeared in significantly different positions, betraying its rapid motion.

    Later, Harvard astronomer Edward Pickering found the star on photographic plates taken in 1888.

    Barnard’s Star is named for this astronomer, E.E. Barnard, seen here posing with the 36? refractor at Lick Observatory. Image via OneMinuteAstronomer.

    UCO Lick Observatory, Mt Hamilton, in San Jose, California

    The UCO Lick C. Donald Shane telescope is a 120-inch (3.0-meter) reflecting telescope located at the Lick Observatory, Mt Hamilton, in San Jose, California

    UC Observatories Lick Aumated Planet Finder, fully robotic 2.4-meter optical telescope at Lick Observatory, situated on the summit of Mount Hamilton, east of San Jose, California, USA

    Lick Observatory, Mt Hamilton, in San Jose, California

    Barnard’s star came to our attention barely 100 years ago and cannot even be seen with the human eye, so the ancients did not know about it. It doesn’t figure into the lore of any constellation or cultural tradition. But that doesn’t mean that it doesn’t a have certain mystique about it that extends beyond the known facts.

    For example, even as long ago as the 1960s and ’70s – long before successful planet-hunters like the Kepler spacecraft – there were suggestions that Barnard’s Star might have a family of planets. At that time, reported discrepancies in the motion of the star led to a claim that at least one Jupiter-size planet orbits it. Although the evidence was disputed and the claim now largely discredited, there is still a chance of planetary discoveries.

    It’s likely due to this rumor of planets that Barnard’s Star has found a place in science fiction. It’s featured in, for example, The Hitchhiker’s Guide to the Galaxy by Douglas Adams; The Garden of Rama by Arthur C. Clarke and Gentry Lee; and several novels of physicist Robert L. Forward. In these works, the hypothetical planets are locations for early colonization or way-stations for exploration further into the cosmos.

    Barnard’s Star also was the hypothetical target of Project Daedalus, a design study by members of the British Interplanetary Society, in which they envisioned an interstellar craft that could reach its destination within a human lifetime.

    Clearly, Barnard’s Star captures peoples’ imaginations!

    Image via BBC/ Sky at Night/ Paul Wootton. Read more.

    How to see Barnard’s Star. Barnard’s Star is faint; its visual magnitude of about 9.5. Thus this star can’t be seen with the eye alone.

    Whats more, its motion – though large in astronomical terms – is still too slow to be noticed in a single night or even easily across a human lifetime.

    Since Barnard’s Star can’t be seen without powerful binoculars or a telescope, finding it requires both experience and perseverance. It is currently located in the constellation Ophiuchus, which is well placed on June, July and August evenings.

    Because Barnard’s Star is a telescopic object, details on how to observe it are beyond the scope of this article, but Britain’s Sky at Night magazine has a good procedure online here: http://bit.ly/2rZNDe1

    Artist’s concept of a red dwarf star – similar to Barnard’s Star – with a planet of about 12 Jupiter-masses. There has been speculation about planets orbiting Barnard’s Star, but none have been confirmed. Also, Barnard’s Star is thought to be considerably older than our sun, which could affect the potential for finding life there. Image via NASA/ ESA/ G. Bacon (STScI)/ Wikimedia Commons.

    The science of Barnard’s Star. The fame of Barnard’s Star is in its novelty, the fact that it moves fastest through Earth’s skies. But its real importance to astronomy lies in the fact that being so close, it is one of the best sources for studying red dwarfs, the most abundant stars in the universe.

    With only about 14% of the solar mass and less than 20% of the radius, it would take roughly seven Barnard’s Stars to match the mass of our sun, and 133 to match our sun’s volume.

    Like all stars, Barnard’s Star shines via thermonuclear fusion, changing light elements (hydrogen) into more massive elements (helium), while releasing enormous amounts of energy. Even so, the lower mass of Barnard’s Star makes it about 2,500 times less powerful than our sun.

    In other words, Barnard’s Star is much dimmer and cooler than our sun. If it replaced the sun in our solar system, it would shine only about four ten-thousandths as brightly as our sun. At the same time, it would be about 100 times brighter than a full moon. No life on Earth would be possible if we orbited Barnard’s Star instead of our sun, however. The much-decreased stellar heat would plunge Earth’s global temperatures to hundreds of degrees below zero.

    Although very common, red dwarfs like Barnard’s Star are typically dim. Thus they are notoriously faint and hard to study. In fact, not a single red dwarf can be seen with the unaided human eye. But because Barnard’s Star is relatively close and bright, it has become a go-to model for all things red dwarf.

    At nearly six light-years’ distance, Barnard’s Star is often cited as the second-closest star to our sun (and Earth). This is true only if you consider the triple star system Alpha Centauri as one star.

    Centauris Alpha Beta Proxima 27, February 2012. Skatebiker

    ESO Pale Red Dot project

    ESO Red Dots Campaign

    Proxima Centauri, the smallest and faintest of Alpha Centauri’s three components, is the closest known star to the sun at just 4.24 light years away. It, too, is a red dwarf. So Barnard’s Star is only the second-closest red dwarf star. It is perhaps more important for astronomical purposes, though, because Proxima is four times fainter and thus harder to study.

    Special thanks to David J. Darling and Jack Schmidling for their help with this article.

    Of course, all stars are moving through the space of our Milky Way galaxy. So even the “fixed” stars move over time. This illustration shows the distances to the nearest stars – including Barnard’s Star – in a time range between 20,000 years in the past and 80,000 years in the future. Image via FrancescoA/ Wikimedia Commons.

    Bottom line: Barnard’s Star is the fastest-moving star in Earth’s skies, in terms of its proper motion. It moves fast because it’s relatively close, only about 6 light-years away.

    See the full article here .

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