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  • richardmitnick 4:54 pm on July 31, 2015 Permalink | Reply
    Tags: , Astronomy, ,   

    From Keck: “Keck Observatory Astronomer Wins Major Prize” Andrea Ghez 

    Keck Observatory

    Keck Observatory

    Keck Observatory

    July 31, 2015
    Christopher Dibble

    1
    Andrea Ghez, Keck Observatory astronomer and UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics.

    UCLA professor and longtime W. M. Keck Observatory astronomer, Andrea Ghez will be awarded the 2015 Bakerian Medal, the Royal Society’s premiere prize lecture in the physical sciences, the organization announced this week.

    “I’m thrilled to receive the Bakerian Medal from the Royal Society,” said Ghez, who is UCLA’s Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics. “The research that is being recognized is the product of a wonderful collaboration among the scientists in the UCLA Galactic Center Group and the University of California’s tremendous investment in the W. M. Keck Observatory. Having cutting-edge tools and a great team makes discovery easy.”

    The medal is accompanied by a cash prize of 10,000 pounds (approximately $15,500), and Ghez will deliver the Bakerian Lecture in London in November. The organization, the oldest scientific academy in continuous existence, cited Ghez’s “acclaimed discoveries using the techniques of optical astronomy, especially her sustained work on the motions and nature of the stars orbiting the black hole in the centre of our Galaxy.”

    “All the data for this project came from Keck Observatory,” Ghez said. “We were able to launch this project 20 years ago because of the unique way that Keck Observatory works. We were able to modify instrumentation and try new approaches to data collection in a way that simply isn’t possible at other observatories. Working at Keck Observatory and with the staff there has been an amazing experience.”

    Since 1995, Ghez has used the Keck Observatory, which sits near the summit of Hawaii’s dormant volcano Maunakea, to study the rotational center of the Milky Way and the movement of thousands of stars close to this galactic center. Keck Observatory operates the two largest and most scientifically productive telescopes on Earth.

    Ghez, a 2008 MacArthur Fellow, uses novel, ground-based telescopic techniques to remove the blurring effects of the Earth’s atmosphere, making the sharpest possible images of the center of our galaxy.

    By measuring the orbits of stars at the center of our galaxy, she showed that a monstrous black hole resides at the center of our Milky Way galaxy, some 26,000 light-years away from Earth, with a mass 4 million times that of the sun. The finding provided the best evidence yet that supermassive black holes exist in our universe. Ghez and her research team have revealed many unexpected mysteries about the role that black holes play in the formation and evolution of galaxies.

    See the full article here.

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    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.
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  • richardmitnick 1:57 pm on July 31, 2015 Permalink | Reply
    Tags: Astronomy, , , , ,   

    From Space.com via SETI Institute: “SETI Targets Kepler-452b, Earth’s ‘Cousin,’ in Search for Alien Life” 


    SETI Institute

    q

    July 31, 2015
    Nola Taylor Redd, SPACE.com Contributor

    Temp 0
    An artist’s concept of the alien Kepler-452b in orbit around its star Kepler-452, which is located 1,400 light-years from Earth. NASA has billed the potentially habitable planet as Earth’s bigger, older cousin.

    Scientists with the SETI (Search for Extraterrestrial Intelligence) Institute have already begun targeting Earth’s “older cousin,” Kepler 452b, the first near-Earth-size world found in the habitable zone of a sun-like star.

    NASA announced the discovery of Kepler-452b last week, billing the planet as the closest thing yet to an Earth 2.0 beyond Earth’s solar system. Researchers have used the Allen Telescope Array [ATA], a collection of 42 radio antennas in northern California, to study the planet for radio signals that could indicate the presence of intelligent extraterrestrial life.

    SETI ATA
    ATA

    So far, the antennas haven’t tuned into any broadcasts.

    “That’s no reason to get discouraged,” Seth Shostak, senior astronomer with the SETI Institute, which is based in Mountain View, California, said during a July 26 webcast by the Slooh Community Observatory.

    “Bacteria, trilobites, dinosaurs—they were here but they weren’t building radio transmitters,” he said.

    Tens of billions of worlds

    Kepler-452 is a sunlike star, located 1,400 light-years from Earth, in the constellation Cygnus. The star’s newly discovered planet, Kepler-452b, has a radius approximately 1.6 times larger than Earth’s. The mass of the planet and its density, which would indicate its composition, have been a bit more challenging to pin down.

    “We would love to be able to do a direct mass measurement so we could measure density,” said Jon Jenkins of NASA’s Ames Research Center in Moffett Field, California, lead author on the paper that identified Kepler-452b. “That would be a big clue as to whether this is a rocky world or a water world or a gassy world.”

    Instead, the team relied on statistics to conclude that the planet has a “better than even chance” of having a composition similar to Earth.

    “The odds slightly favor this planet being rocky,” Jenkins said.

    Based on its size, orbit and star, Kepler-452b is the closest analogue to Earth yet discovered, its discoverers and NASA officials have said.

    Kepler-452b orbits its star once every 385 days, about three weeks longer than Earth takes to travel around the sun. This orbit places the planet squarely in what scientists call the “habitable zone,” the region around a star where liquid water could exist at a planet’s surface. Water is thought to be a key requirement for life to evolve, so Kepler-452b is one of the best potentially habitable worlds found to date.

    SETI Institute researchers are using the Allen Telescope Array, a collection of 6-meter (20 feet) telescopes in the Cascade Mountains of California, to observe Kepler-452b. So far, the array has observed the exoplanet on over 2 billion frequency bands, with no result. The telescopes will continue to observe over a total of 9 billion channels, searching for signals of alien intelligence.

    “There are three ways to find life in space,” Shostak said. The first is to “go there and look”, as humans are doing on Mars and the moons of the solar system, he said. For planets like Kepler-452b, which lie so far from the solar system, such a trip would be a challenge with today’s technology.

    The second is to “build big telescopes and analyze the light bouncing off of a planet,” Shostak said. NASA’s Hubble Space Telescope has already begun to probe the atmospheres of distant planets.

    NASA Hubble Telescope
    NASA/ESA Hubble

    However, Jenkins said, the host star is too dim to allow for this sort of examination with either Hubble or its successor, the James Webb Space Telescope.

    NASA Webb Telescope
    Webb

    The third way to find life in space is to search for signals that could indicate intelligence. “That’s what SETI does,” Shostak said.

    Both Shostak and Jenkins emphasized that what makes Kepler-452b truly important is what it indicates for the wide population of planets beyond the solar system. Before this planet’s discovery, no sun-like stars had been found to host rocky worlds in their habitable zones, making Earth fairly unique in the known galaxy. Although statistics suggested many such planets orbited other stars, no such worlds had been observed with modern instruments.

    Jenkins noted that the existence of Kepler-452b suggests similar finds will be made in the near future.

    “We have a really good opportunity in the future to find a similar-size planet in a similar-size orbit about a similar star far closer to us,” he said.

    Unlike the distant exoplanet, a closer exoplanet could have its atmosphere probed for potential signatures of life.

    “What you really want to know is what [fraction] of planets could be habitable,” Shostak said. He added that Kepler-452b suggests that fraction is perhaps one in five, or even one in three.

    “There could be tens of billions of such worlds in the galaxy,” Shostak said.

    See the full article here.

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  • richardmitnick 11:28 am on July 31, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From JPL- “Exoplanets 20/20: Looking Back to the Future: 

    JPL

    July 31, 2015
    Pat Brennan, NASA-JPL

    1
    Artist’s rendering of a Jupiter-sized exoplanet and its host, a star slightly more massive than our sun. Image credit: ESO

    Geoff Marcy remembers the hair standing up on the back of his neck. Paul Butler remembers being dead tired. The two men had just made history: the first confirmation of a planet orbiting another star.

    The groundbreaking discovery had been announced less than week earlier by the European team of Michel Mayor and Didier Queloz. But the news was met with some initial skepticism in the astronomical community. By a stroke of good luck, Marcy and Butler happened to have previously scheduled observation time on a 120-inch telescope at the Lick Observatory, atop California’s Mount Hamilton.

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    UCO Lick Shane 120″ telescope

    The scientists, who would become two of the world’s most famous planet hunters, remember driving down the mountainside together in October 1995. They’d spent four straight nights making their observations. And while further processing would be needed to make the scientific case, their data seemed clear and unmistakable — and almost impossible. A huge planet, at least half the size of Jupiter, was not only orbiting its host star more tightly than Mercury hugs the sun. It was racing around that star, making a complete orbit in just four days.

    The planet, called 51 Pegasi b, would open a new era in humanity’s exploration of our galactic neighborhood. It would be the first in a series of “hot Jupiters” — giant planets in fast, tight orbits — discovered in rapid succession. The rush of new worlds would propel Marcy, Butler and their research team into the media spotlight, and forever change our view of the cosmos.

    ‘A spine-tingling experience’

    But for the moment, on that solemn drive down the mountainside, Marcy and Butler were alone with their world-altering news. “We knew we were the only people on the planet to be sure that 51 Peg, the planet, really did exist,” Marcy said recently. “It was exhilarating. We were absolutely thrilled to know an historic moment in science history was happening before our eyes. It was a truly spine-tingling experience.”

    Still, the astronomical pioneers had a few struggles ahead to gain the acceptance of the scientific community. The hunt for extrasolar planets — exoplanets, for short — had a poor track record, with decades’ worth of false detections. Among them was the thrilling discovery of a planet orbiting Barnard’s star in the 1960s; it turned out to be an unnoticed shift of a telescope lens. Once the shift was accounted for, the “planet” disappeared.

    The early ’90s had seen the actual detection of “pulsar planets,” but these seemed too strange to count, orbiting a rapidly spinning, radiation-spewing stellar remnant called a pulsar. Most scientists would reserve the “first” designation for a planet orbiting a normal star.

    “The whole field had a snake-oil sort of feel to it,” Butler said in a recent interview. “For the previous fifty years or so, there were many announcements, all proved to be wrong. If we went to a meeting and said we were looking for extrasolar planets, we might as well have said we were looking for little green men.”

    Even Marcy greeted the announcement of 51 Peg, made at a scientific conference in Florence, Italy, by Mayor and Queloz, with a bit of a yawn — at first.

    “This claim on October 6, 1995, of the first planet ever discovered was sort of business as usual,” he said. “Here’s another false claim. This one is more obviously a false claim. The orbital period is claimed to be 4.3 days. Nobody in their right mind thought planets could orbit so close to a star.”

    But the four nights of observations at the Lick Observatory — perfectly coinciding with 51 Peg’s four-day orbit — changed all that. Both the Mayor and Marcy teams had been trying to develop a planet-hunting technique based on wobbling stars. The wobbles, known as the star’s “radial velocity,” were induced by the gravitational tugs of orbiting planets. The starlight wavelength was compressed, then stretched, as the star moved toward and away from astronomers’ telescopes.

    Now, Mayor and Queloz had proven that the technique worked. And a few days later, Marcy and Butler validated both the method used by Mayor’s team and their own very similar detection method.

    But Marcy and his team realized something more. The only thing that had kept them from beating Mayor’s group to that first detection was a perfectly reasonable assumption: that big planets moved in stately orbits, like the 12 years it took Jupiter to take one lap around the sun.

    Either they would have to watch stars for a very long time, or they would have to refine their wobble detector until it could pick up the very tiny shifts in a star’s position caused by small planets in tighter, faster orbits.

    They were working on just this type of refinement when Mayor announced his discovery. More importantly, they had been recording observations with their wobble-detecting device, known as a spectrograph. Sure enough, when they took another look, big, star-hugging planets began popping out of their data.

    Planets proper

    At a meeting of the American Astronomical Society in January 1996, Marcy announced two more planet discoveries: 70 Virginis and 47 Ursae Majoris. The first had a 116-day orbit — far more reasonable than 51 Peg’s scorching four days — and its orbit was elliptical, making it unlikely to be anything but a planet. The orbit of 47 Ursae Majoris was more reasonable still: 2.5 years. Together, they provided a “bridge” to our own solar system, Marcy said, with planets behaving themselves as proper planets should.

    The discoveries vaulted Marcy and his team into scientific celebrity status, with appearances on nationwide nightly news shows; their new planets even made the cover of Time magazine.

    And the Marcy-Butler team was just warming up. The floodgates were opened. They discovered at least 70 of the first 100 exoplanets that were found in the years that followed. Their pioneering, planet-hunting safari went on for a decade. Soon, however, the landscape would change yet again.

    The gold rush of planet finding kicked into high gear with the launch of the Kepler Space Telescope in 2009.

    NASA Kepler Telescope
    Kepler

    This spacecraft nestled into an Earth-trailing orbit, then fixed its eye on a small patch of sky — and kept it there for four years.

    Within that patch were more than 150,000 stars, a kind of cross-section of an arm of our own Milky Way galaxy, as if Kepler were shining a searchlight into deep space. Kepler was looking for planetary transits — the infinitesimally tiny dip in starlight that occurs when a planet crosses the face of the star it is orbiting.

    The method only works for distant solar systems whose planets’ orbits, from our perspective, are seen edge-on. This way, an exoplanet is silhouetted as it passes between Kepler and its host star, reducing the starlight measured by Kepler.

    The fifth time’s the charm

    Kepler was the brainchild of William Borucki of the NASA Ames Research Center in Moffet Field, California. Borucki, who retired in early July 2015, doggedly pressed his case for Kepler. During the ’90s, his proposed designs were rejected no less than four times. He finally won approval from NASA in 2001.

    But no one knew what Kepler might find, or even if it would find anything at all.

    “We launched Kepler, to some extent, like Magellan or Columbus went to sea, not knowing quite what we were going to encounter,” said James Fanson, deputy manager in the Instruments Division at NASA’s Jet Propulsion Laboratory in Pasadena, California. Fanson was Kepler’s project manager when the spacecraft was launched.

    “We knew we were going to make history,” he said. “We just didn’t know what history we were going to make.”

    Kepler’s transit watch paid off, however, identifying more than 4,600 candidate planets hundreds to thousands of light-years distant. So far, 1,028 of those have been confirmed — some of them Earth-sized planets that orbit within their star’s so-called habitable zone, where liquid water can exist on a planet. Scientists are still mining Kepler data, regularly turning up new planetary candidates and confirming earlier finds.

    Kepler itself ended its initial mission in 2013, when two of four reaction wheels used to keep the spacecraft in a stable position failed. But the Kepler science team developed clever ways to continue squeezing useful data out of the space telescope, relying on the subtle pressure of sunlight to stabilize it on one axis. Kepler is now in its second phase of life, and it’s still discovering planets.

    Preceding Kepler was the groundbreaking COROT satellite, a European venture launched in 2006 that discovered numerous planets before it ceased functioning in 2012 — including the first rocky planet found to orbit a sun-like star. COROT used the transit method to detect exoplanets, and was the first space mission dedicated to that purpose.

    ESA CoRoT
    ESA/CoRoT

    The prolific discoveries still flowing from the Hubble Space Telescope include not only exoplanets, but characterizations of exoplanet atmospheres, identifying a variety of gases. And the Spitzer Space Telescope has found water vapor in exoplanetary atmospheres as well as weather patterns.

    NASA Hubble Telescope
    NASA/ESA Hubble

    Both the wobble and transit methods, relied upon by the exoplanet pioneers, are still in use today, along with several other techniques. And 20 years after the first discovery, the exoplanet total is up to more than 5,000 candidates, with more than 1,800 of those confirmed.

    A new reality

    The galaxy, it seems, is crowded with planets. Yet we are not yet able to answer the big question: Are we alone?

    A new generation of telescopes in the years and decades ahead, on the ground and in space, will continue to search for an answer. One critical tool will be the same one pioneered by Marcy and the other early planet hunters: spectroscopy. They used this method to dissect the light coming from distant stars, revealing their back-and-forth, planet-induced wobbling as the starlight was stretched and compressed; the newest generation of instruments will do the same thing to the light from the atmospheres of exoplanets. Splitting this planetary light into its constituent parts, a little like the rainbow colors of sunlight shining through a prism, should reveal which gases and chemicals are present in those alien skies.

    And one day, some of those atmospheric constituents might suggest the presence of life far beyond planet Earth.

    For more information about exoplanets and NASA’s planet-finding program, visit:

    http://planetquest.jpl.nasa.gov

    See the full article here.

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    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge [1], on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 9:46 am on July 31, 2015 Permalink | Reply
    Tags: Astronomy, , Vatican   

    From phys.org: “Vatican sceptical about close encounters of the third kind” 

    physdotorg
    phys.org

    July 31, 2015
    Ella Ide And Laure Brumont

    1
    A man looks at an astronomical telescope at the Vatican Astronomical Observatory, or “Specola Vaticana”, in Albano Laziale, 40 km south of Rome, on July 30, 2015

    The recent discovery of an Earth twin has boosted chances there is intelligent life on other planets. But while Pope Francis’s telescope scans the starlit skies, the Vatican is sceptical of ever meeting Mr. Spock.

    On a leafy hilltop near the papal summer home of Castel Gandolfo sits the Vatican’s Observatory, one of the oldest astronomical research institutions in the world, where planetary scientists mix the study of meteorites and the Big Bang theory with theology.

    Vatican Observatory
    Vatican Observatory

    Boasting a prestigious research centre at the University of Arizona in the United States, the institute has never shied away from asking whether there could be life on other planets and is thrilled with the discovery of an “Earth 2.0″.

    U Arizona Steward Observatory Vatican Advanced Technology Telescope
    U Arizona Steward Observatory Vatican Advanced Technology Telescope Interior
    U Arizona Vatican Advanced Technology Telescope

    Astronomers hunting for a planet like ours announced to huge excitement last week that they have found the closest match yet, Kepler 452b, which is circling its star at the same distance as our home orbits the Sun.

    Around 60 percent larger than Earth, it sits squarely in the Goldilocks zone of its star, where life could exist because it is neither too hot nor too cold to support liquid water, according to the US space agency NASA.

    The discovery “is great news”, the Observatory’s Argentine director Jose Funes told AFP, despite the fact that scientists suspect increasing energy from the planet’s ageing sun might now be heating the surface and evaporating any oceans, making life difficult.

    However, while “it is probable there was life and perhaps a form of intelligent life… I don’t think we’ll ever meet a Mr. Spock”, he said.

    The problem is that Kepler 452b is 1,400 light-years away—an impossible distance to cover using mankind’s current technology.

    No Jesus 2.0

    NASA may have made history this year with a Pluto fly-by, but it took nine years for its probe to get there despite the planet being under six light hours away. The fastest spaceship in the Solar System, it would take some 11 million years to reach the Earth’s cousin.

    Funes, who has a degree in theology and doctorate in astronomy, would not be drawn on whether the Vatican would send out space missionaries to convert alien life-forms to Christianity if extra-terrestrial life was found elsewhere.

    What is clear, he says, is that while God may have created aliens and planets similar to Earth, there can be no second Jesus.

    “The discovery of intelligent life does not mean there’s another Jesus,” he insisted, because “the incarnation of the son of God is a unique event in the history of humanity, of the Universe”.

    Neat in his black cassock and surrounded by the latest astrological publications, Funes, 52, says science and religion co-exist perfectly together, insisting “if there was intelligent life (on another planet), I don’t see that as a contradiction with the Christian faith”.

    “The bible is not a scientific book. If we look for scientific responses to our questions in the bible, we are making a mistake,” he said.

    “It answers great questions, like ‘what is our role in the Universe?'” But such answers can also come from exploring the stars, he said.

    “This type of research, the search for life in the Universe, helps us to understand ourselves… to understand our potential, but also our limits”.

    See the full article here.

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    About Phys.org in 100 Words

    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 9:22 am on July 31, 2015 Permalink | Reply
    Tags: Astronomy, ,   

    From phys.org: “Binary star system precisely timed with pulsar’s gamma-rays” 

    physdotorg
    phys.org

    July 31, 2015
    No Writer Credit

    1
    In the binary system, the pulsar and its companion star orbit the the common center of mass in only 4.6 hours. The companion is heated on one side by the pulsar’s radiation (magenta) and is slowly evaporated. The binary system and the companion are to scale, the pulsar has been magnified. Credit: Knispel/AEI/SDO/AIA/NASA/DSS

    Pulsars are rapidly rotating compact remnants born in the explosions of massive stars. They can be observed through their lighthouse-like beams of radio waves and gamma-rays. Scientists at the Max Planck Institute for Gravitational Physics (Albert Einstein Institute, AEI) in Hannover, Germany, now have precisely measured the properties of a binary star system with a gamma-ray millisecond pulsar. Using new methods, the researchers analyzed archival data from the Fermi Gamma-ray Space Telescope more precisely than possible before.

    NASA Fermi Telescope
    Fermi

    They discovered variations in the orbital period of the interacting binary system that can be explained by magnetic activity cycles of the companion star.

    0FGL J2339.8–0530 – that is the catalog name of a celestial object which the Large Area Telescope (LAT) on board the Fermi Gamma-ray Space Telescope identified as a source of intense gamma radiation in 2009.

    NASA Fermi LAT
    LAT on Fermi

    Observations at other wavelengths in the following years suggested a possible explanation for its nature: a millisecond pulsar in a binary system with a companion star, each orbiting their common center of mass every 4.6 hours.

    Only in 2014 could the pulsar now known as “PSR J2339–0533″ be identified through its pulsed radio emission. The observations at radio wavelengths are hampered through the interaction of the pulsar with its stellar partner. The pulsar’s radiation heats the companion and slowly vaporizes it. This causes clouds of gas to drift through the binary system, which absorb the radio emission and temporarily make the pulsar invisible. To completely characterize the system, regular observations over several years would be required.

    Clear View with Gamma-rays

    However, the gamma-rays emitted by PSR J2339–0533 penetrate the gas clouds and enable observations of the pulsar. “The photon arrival times registered by the Fermi-LAT depend on the physical properties of the stars and their orbits,” says Holger Pletsch, leader of an independent research group at the AEI and lead author the paper now published in The Astrophysical Journal.

    In turn, a precise measurement of the binary system’s physical parameters can be inferred from an analysis of the photon arrival times. “After the first radio observations we immediately had a starting point. We knew we could use archival Fermi-LAT data from the past six years to study the system at high precision”, says Pletsch.

    2
    The companion’s magnetic activity affects the orbital period of the binary system. The changing magnetic field interacts with the plasma inside the star and deforms it. As the shape of the star varies its gravitational field also changes, which in turn affects the pulsar orbit (right). This can explain the observed orbital period variations (left). The binary system and the companion are to scale, the pulsar has been magnified. The companion’s deformation is exaggerated. Credit: Knispel/AEI/SDO/AIA/NASA

    Precise Measurement with New Methods

    The use of new analysis algorithms was key. “Unlike previous methods that average the arrival times of many gamma-ray photons and lose time resolution as a consequence, our method is based on the arrival times of single photons”, says Colin Clark, a PhD student in Pletsch’s research group and co-author of the paper. “This allows us to measure the physical properties of the binary system to higher precision, especially on short time scales.”

    Pletsch’s and Clark’s results provide a very precise measurement of PSR J2339–0533, its companion, and their mutual orbits. This is the first such measurement of an interacting binary system through the gamma-ray emission of a millisecond pulsar. The scientists make full use of the Fermi-LAT time resolution, which is a few millionths of a second.

    Magnetic Activity Varies the Orbital Period

    The results show an unexpected variation of the orbital period. “We were surprised to discover that the orbital period slowly varies around the mean of 4.6 hours. The variations are a few thousands of a second, but compared to the measurement precision of millionths of a seconds, this is a lot”, says Clark. “For the Earth’s orbit this would mean that some years would be shorter or longer than others by a dozen seconds.”

    The most likely cause for these variations are tiny changes in the shape of the companion caused by its magnetic activity. Similar to our Sun the companion might be going through activity cycles. The changing magnetic field interacts with the plasma inside the star and deforms it. As the shape of the star varies its gravitational field also changes, which in turn affects the pulsar orbit. This can explain the observed orbital period variations.

    “In the future simultaneous observations with optical telescopes can help us to prove the causal relationship between stellar activity and orbital period variations”, says Pletsch. These observations can also improve our understanding of the binary system. “In a sense, the Fermi-LAT observations of the pulsar allow us to peek inside the companion. This might even be used to determine the type of magnetic dynamo in the star.”

    See the full article here.

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    Phys.org™ (formerly Physorg.com) is a leading web-based science, research and technology news service which covers a full range of topics. These include physics, earth science, medicine, nanotechnology, electronics, space, biology, chemistry, computer sciences, engineering, mathematics and other sciences and technologies. Launched in 2004, Phys.org’s readership has grown steadily to include 1.75 million scientists, researchers, and engineers every month. Phys.org publishes approximately 100 quality articles every day, offering some of the most comprehensive coverage of sci-tech developments world-wide. Quancast 2009 includes Phys.org in its list of the Global Top 2,000 Websites. Phys.org community members enjoy access to many personalized features such as social networking, a personal home page set-up, RSS/XML feeds, article comments and ranking, the ability to save favorite articles, a daily newsletter, and other options.

     
  • richardmitnick 8:14 pm on July 30, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From phys.org: “Earth’s magnetic shield is much older than previously thought” 

    physdotorg
    phys.org

    July 30, 2015
    U Rochester

    1
    An artist’s depiction of Earth’s magnetic field deflecting high-energy protons from the sun four billion years ago. Note: The relative sizes of the Earth and Sun, as well as the distances between the two bodies, are not drawn to scale. Credit: Graphic by Michael Osadciw/University of Rochester.

    Since 2010, the best estimate of the age of Earth’s magnetic field has been 3.45 billion years. But now a researcher responsible for that finding has new data showing the magnetic field is far older.

    John Tarduno, a geophysicist at the University of Rochester and a leading expert on Earth’s magnetic field, and his team of researchers say they believe the Earth’s magnetic field is at least four billion years old.

    “A strong magnetic field provides a shield for the atmosphere,” said Tarduno, “This is important for the preservation of habitable conditions on Earth.”

    The findings by Tarduno and his team have been published in the latest issue of the journal Science.

    Earth’s magnetic field protects the atmosphere from solar winds—streams of charged particles shooting from the Sun. The magnetic field helps prevent the solar winds from stripping away the atmosphere and water, which make life on the planet possible.

    Earth’s magnetic field is generated in its liquid iron core, and this “geodynamo” requires a regular release of heat from the planet to operate. Today, that heat release is aided by plate tectonics, which efficiently transfers heat from the deep interior of the planet to the surface.

    2
    The tectonic plates of the world were mapped in the second half of the 20th century.

    But, according to Tarduno, the time of origin of plate tectonics is hotly debated, with some scientists arguing that Earth lacked a magnetic field during its youth.

    Given the importance of the magnetic field, scientists have been trying to determine when it first arose, which could, in turn, provide clues as to when plate tectonics got started and how the planet was able to remain habitable.

    Fortunately for scientists, there are minerals—such as magnetite—that lock in the magnetic field record at the time the minerals cooled from their molten state. The oldest available minerals can tell scientists the direction and the intensity of the field at the earliest periods of Earth’s history. In order to get reliable measurements, it’s crucial that the minerals obtained by scientists are pristine and never reached a sufficient heat level that would have allowed the old magnetic information within the minerals to reset to the magnetic field of the later time.

    The directional information is stored in microscopic grains inside magnetite- a naturally occurring magnetic iron oxide. Within the smallest magnetite grains are regions that have their own individual magnetizations and work like a tape recorder. Just as in magnetic tape, information is recorded at a specific time and remains stored unless it is replaced under specific conditions.

    Tarduno’s new results are based on the record of magnetic field strength fixed within magnetite found within zircon crystals collected from the Jack Hills of Western Australia.

    3
    Jack Hills satellite image

    The zircons were formed over more than a billion years and have come to rest in an ancient sedimentary deposit. By sampling zircons of different age, the history of the magnetic field can be determined.

    The ancient zircons are tiny—about two-tenths of a millimeter—and measuring their magnetization is a technological challenge. Tarduno and his team used a unique superconducting quantum interference device, or SQUID magnetometer, at the University of Rochester that provides a sensitivity ten times greater than comparable instruments.

    But in order for today’s magnetic intensity readings of the magnetite to reveal the actual conditions of that era, the researchers needed to make sure the magnetite within the zircon remained pristine from the time of formation.

    Of particular concern was a period some 2.6 billion years ago during which temperatures in the rocks of the Jack Hills reached 475?C. Under those conditions, it was possible that the magnetic information recorded in the zircons would have been erased and replaced by a new, younger recording of Earth’s magnetic field.

    “We know the zircons have not been moved relative to each other from the time they were deposited,” said Tarduno. “As a result, if the magnetic information in the zircons had been erased and re-recorded, the magnetic directions would have all been identical.”

    Instead, Tarduno found that the minerals revealed varying magnetic directions, convincing him that the intensity measurements recorded in the samples were indeed as old as four billion years.

    The intensity measurements reveal a great deal about the presence of a geodynamo at the Earth’s core. Tarduno explains that solar winds could interact with the Earth’s atmosphere to create a small magnetic field, even in the absence of a core dynamo. Under those circumstances, he calculates that the maximum strength of a magnetic field would be 0.6 uT (micro-Teslas). The values measured by Tarduno and his team were much greater than 0.6 ?T, indicating the presence of a geodynamo at the core of the planet, as well as suggesting the existence of the plate tectonics needed to release the built-up heat.

    “There has been no consensus among scientists on when plate tectonics began,” said Tarduno. “Our measurements, however, support some previous geochemical measurements on ancient zircons that suggest an age of 4.4 billion years.”

    The magnetic field was of special importance in that eon because solar winds were about 100 times stronger than today. In the absence of a magnetic field, Tarduno says the protons that make up the solar winds would have ionized and stripped light elements from the atmosphere, which, among other things, resulted in the loss of water.

    Scientists believe that Mars had an active geodynamo when that planet was formed, but that it died off after four billion years. As a result, Tarduno says, the Red Planet had no magnetic field to protect the atmosphere, which may explain why its atmosphere is so thin.

    “It may also be a major reason why Mars was unable to sustain life,” said Tarduno.

    See the full article here.

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  • richardmitnick 4:06 pm on July 30, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From JPL: “NASA’s Spitzer Confirms Closest Rocky Exoplanet” 

    JPL

    July 30, 2015
    Felicia Chou NASA Headquarters, Washington
    202-358-0257
    felicia.chou@nasa.gov

    Whitney Clavin
    Jet Propulsion Laboratory, Pasadena, Calif.
    818-354-4673
    whitney.b.clavin@jpl.nasa.gov

    1
    This artist’s conception shows the silhouette of a rocky planet, dubbed HD 219134b, as it passes in front of its star. At 21 light-years away, the planet is the closest outside of our solar system that can be seen crossing, or transiting, its star — a bonus for astronomers because transiting planets make ideal specimens for detailed studies of their atmospheres. It was discovered using the HARPS-North instrument on the Italian 3.6-meter National Galileo Telescope in the Canary Islands, and NASA’s Spitzer Space Telescope.

    The planet, which is about 1.6 times the size of Earth, is also the nearest confirmed rocky planet outside our solar system. It orbits a star that is cooler and smaller than our sun, whipping closely around it in a mere three days. The proximity of the planet to the star means that it would be scorching hot and not habitable.

    Transiting planets are ideal targets for astronomers wanting to know more about planetary compositions and atmospheres. As a planet passes in front of its star, it causes the starlight to dim, and telescopes can measure this effect. If molecules are present in the planet’s atmosphere, they can absorb certain wavelengths of light, leaving imprints in the starlight. This type of technique will be used in the future to investigate potentially habitable planets and search for signs of life.

    2
    This sky map shows the location of the star HD 219134 (circle), host to the nearest confirmed rocky planet found to date outside of our solar system. The star lies just off the “W” shape of the constellation Cassiopeia and can be seen with the naked eye in dark skies. It actually has multiple planets, none of which are habitable.

    3
    This artist’s rendition shows one possible appearance for the planet HD 219134b, the nearest confirmed rocky exoplanet found to date outside our solar system. The planet is 1.6 times the size of Earth, and whips around its star in just three days. Scientists predict that the scorching-hot planet — known to be rocky through measurements of its mass and size — would have a rocky, partially molten surface with geological activity, including possibly volcanoes.

    Using NASA’s Spitzer Space Telescope, astronomers have confirmed the discovery of the nearest rocky planet outside our solar system, larger than Earth and a potential gold mine of science data.

    NASA Spitzer Telescope
    Spitzer

    Dubbed HD 219134b, this exoplanet, which orbits too close to its star to sustain life, is a mere 21 light-years away. While the planet itself can’t be seen directly, even by telescopes, the star it orbits is visible to the naked eye in dark skies in the Cassiopeia constellation, near the North Star.

    HD 219134b is also the closest exoplanet to Earth to be detected transiting, or crossing in front of, its star and, therefore, perfect for extensive research.

    “Transiting exoplanets are worth their weight in gold because they can be extensively characterized,” said Michael Werner, the project scientist for the Spitzer mission at NASA’s Jet Propulsion Laboratory in Pasadena, California. “This exoplanet will be one of the most studied for decades to come.”

    The planet, initially discovered using the HARPS-North instrument on the Italian 3.6-meter Galileo National Telescope in the Canary Islands, is the subject of a study accepted for publication in the journal Astronomy & Astrophysics

    Telescoipio Nazionale Galileo.
    Galileo National Telescope

    Telescopio Nazionale Galileo - Harps North
    HARPS-North instrument

    Study lead author Ati Motalebi of the Geneva Observatory in Switzerland said she believes the planet is the ideal target for NASA’s James Webb Space Telescope in 2018.

    NASA James Webb Telescope
    Webb

    “Webb and future large, ground-based observatories are sure to point at it and examine it in detail,” Motalebi said.

    Only a small fraction of exoplanets can be detected transiting their stars due to their relative orientation to Earth. When the orientation is just right, the planet’s orbit places it between its star and Earth, dimming the detectable light of its star. It’s this dimming of the star that is actually captured by observatories such as Spitzer and can reveal not only the size of the planet but also clues about its composition.

    “Most of the known planets are hundreds of light-years away. This one is practically a next-door neighbor,” said astronomer and study co-author Lars A. Buchhave of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts. For reference, the closest known planet is GJ674b at 14.8 light-years away; its composition is unknown.

    HD 219134b was first sighted by the HARPS-North instrument and a method called the radial velocity technique, in which a planet’s mass and orbit can be measured by the tug it exerts on its host star. The planet was determined to have a mass 4.5 times that of Earth, and a speedy three-day orbit around its star.

    Spitzer followed up on the finding, discovering the planet transits its star. Infrared measurements from Spitzer revealed the planet’s size, about 1.6 times that of Earth. Combining the size and mass gives it a density of 3.5 ounces per cubic inch (six grams per cubic centimeter) — confirming HD 219134b is a rocky planet.

    Now that astronomers know HD 219134b transits its star, scientists will be scrambling to observe it from the ground and space. The goal is to tease chemical information out of the dimming starlight as the planet passes before it. If the planet has an atmosphere, chemicals in it can imprint patterns in the observed starlight.

    Rocky planets such as this one, with bigger-than-Earth proportions, belong to a growing class of planets termed super-Earths.

    “Thanks to NASA’s Kepler mission, we know super-Earths are ubiquitous in our galaxy, but we still know very little about them,” said co-author Michael Gillon of the University of Liege in Belgium, lead scientist for the Spitzer detection of the transit.

    NASA Kepler Telescope
    Kepler

    “Now we have a local specimen to study in greater detail. It can be considered a kind of Rosetta Stone for the study of super-Earths.”

    Further observations with HARPS-North also revealed three more planets in the same star system, farther than HD 219134b. Two are relatively small and not too far from the star. Small, tightly packed multi-planet systems are completely different from our own solar system, but, like super-Earths, are being found in increasing numbers.

    JPL manages the Spitzer mission for NASA’s Science Mission Directorate in Washington. Science operations are conducted at the Spitzer Science Center at the California Institute of Technology in Pasadena. Spacecraft operations are based at Lockheed Martin Space Systems Co. in Littleton, Colorado. Data are archived at the Infrared Science Archive, housed at Caltech’s Infrared Processing and Analysis Center.

    For more information about NASA’s Spitzer Space Telescope, visit:

    http://www.nasa.gov/spitzer

    See the full article here.

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    NASA JPL Campus

    Jet Propulsion Laboratory (JPL) is a federally funded research and development center and NASA field center located in the San Gabriel Valley area of Los Angeles County, California, United States. Although the facility has a Pasadena postal address, it is actually headquartered in the city of La Cañada Flintridge, on the northwest border of Pasadena. JPL is managed by the nearby California Institute of Technology (Caltech) for the National Aeronautics and Space Administration. The Laboratory’s primary function is the construction and operation of robotic planetary spacecraft, though it also conducts Earth-orbit and astronomy missions. It is also responsible for operating NASA’s Deep Space Network.

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  • richardmitnick 3:42 pm on July 30, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From Keck: “Telescopes Team Up to Find Distant Uranus-Sized Planet Through Microlensing” 

    Keck Observatory

    Keck Observatory

    Keck Observatory

    July 30, 2015
    SCIENCE CONTACT
    Dave Bennett
    University of Notre Dame
    bennett@nd.edu
    574-315-6621

    Jean-Phillipe Beaulieu
    Institut d’Astrophysique de Paris
    Beaulieu@iap.fr
    +33 6 03 98 73 11

    MEDIA CONTACT
    Steve Jefferson
    W. M. Keck Observatory
    sjefferson@keck.hawaii.edu
    808-881-3827

    1
    Credit: NASA, ESA, and A. Feild (STScI)

    The W. M. Keck Observatory in Hawaii and NASA’s Hubble Space Telescope have made independent confirmations of an exoplanet orbiting far from its central star.

    NASA Hubble Telescope
    NASA/ESA Hubble

    The planet was discovered through a technique called gravitational microlensing. This finding opens a new piece of discovery space in the extrasolar planet hunt: to uncover planets as far from their central stars as Jupiter and Saturn are from our sun. The Hubble and Keck Observatory results will appear in two papers in the July 30 edition of The Astrophysical Journal.

    The large majority of exoplanets cataloged so far are very close to their host stars because several current planet-hunting techniques favor finding planets in short-period orbits. But this is not the case with the microlensing technique, which can find more distant and colder planets in long-period orbits that other methods cannot detect.

    Microlensing occurs when a foreground star amplifies the light of a background star that momentarily aligns with it. If the foreground star has planets, then the planets may also amplify the light of the background star, but for a much shorter period of time than their host star. The exact timing and amount of light amplification can reveal clues to the nature of the foreground star and its accompanying planets.

    “Microlensing is currently the only method to detect the planets close to their birth place,” said team member, Jean-Philippe Beaulieu, Institut d’Astrophysique de Paris. “Indeed, planets are being mostly formed at a certain distance from the central star where it is cold enough for volatile compounds to condense into solid ice grains. These grains will then aggregate and will ultimately evolve into planets.”

    The system, cataloged as OGLE-2005-BLG-169, was discovered in 2005 by the Optical Gravitational Lensing Experiment (OGLE), the Microlensing Follow-Up Network (MicroFUN), and members of the Microlensing Observations in Astrophysics (MOA) collaborations—groups that search for extrasolar planets through gravitational microlensing.

    Without conclusively identifying and characterizing the foreground star, however, astronomers have had a difficult time determining the properties of the accompanying planet. Using Hubble and the Keck Observatory, two teams of astronomers have now found that the system consists of a Uranus-sized planet orbiting about 370 million miles from its parent star, slightly less than the distance between Jupiter and the sun. The host star, however, is about 70 percent as massive as our sun.

    “These chance alignments are rare, occurring only about once every 1 million years for a given planet, so it was thought that a very long wait would be required before the planetary microlensing signal could be confirmed,” said David Bennett, the lead of the team that analyzed the Hubble data. “Fortunately, the planetary signal predicts how fast the apparent positions of the background star and planetary host star will separate, and our observations have confirmed this prediction. The Hubble and Keck Observatory data, therefore, provide the first confirmation of a planetary microlensing signal.”

    In fact, microlensing is such a powerful tool that it can uncover planets whose host stars cannot be seen by most telescopes. “It is remarkable that we can detect planets orbiting unseen stars, but we’d really like to know something about the stars that these planets orbit,” explained Virginie Batista, leader of the Keck Observatory analysis. “The Keck and Hubble telescopes allow us to detect these faint planetary host stars and determine their properties.”

    Planets are small and faint compared to their host stars; only a few have been observed directly outside our solar system. Astronomers often rely on two indirect techniques to hunt for extrasolar planets. The first method detects planets by the subtle gravitational tug they give to their host stars. In another method, astronomers watch for small dips in the amount of light from a star as a planet passes in front of it.

    Both of these techniques work best when the planets are either extremely massive or when they orbit very close to their parent stars. In these cases, astronomers can reliably determine their short orbital periods, ranging from hours to days to a couple years.

    But to fully understand the architecture of distant planetary systems, astronomers must map the entire distribution of planets around a star. Astronomers, therefore, need to look farther away from the star—from about the distance of Jupiter is from our sun, and beyond.

    “It’s important to understand how these systems compare with our solar system,” said team member Jay Anderson of the Space Telescope Science Institute in Baltimore, MD. “So we need a complete census of planets in these systems. Gravitational microlensing is critical in helping astronomers gain insights into planetary formation theories.”

    The planet in the OGLE system is probably an example of a “failed-Jupiter” planet, an object that begins to form a Jupiter-like core of rock and ice weighing around 10 Earth masses, but it doesn’t grow fast enough to accrete a significant mass of hydrogen and helium. So it ends up with a mass more than 20 times smaller than that of Jupiter. “Failed-Jupiter planets, like OGLE-2005-BLG-169Lb, are predicted to be more common than Jupiters, especially around stars less massive than the sun, according to the preferred theory of planet formation. So this type of planet is thought to be quite common,” Bennett said.

    Microlensing takes advantage of the random motion of stars, which are generally too small to be noticed without precise measurements. If one star, however, passes nearly precisely in front of a farther background star, the gravity of the foreground star acts like a giant lens, magnifying the light from the background star.

    A planetary companion around the foreground star can produce a variation in the brightening of the background star. This brightening fluctuation can reveal the planet, which can be too faint, in some cases, to be seen by telescopes. The duration of an entire microlensing event is several months, while the variation in brightening due to a planet lasts a few hours to a couple of days.

    The initial microlensing data of OGLE-2005-BLG-169 had indicated a combined system of foreground and background stars plus a planet. But due to the blurring effects of our atmosphere, a number of unrelated stars are also blended with the foreground and background stars in the very crowded star field in the direction of our galaxy’s center.

    “The Hubble Space telescope and KECK2 are unique facilities providing complementary high angular resolution observations to characterise these cold planets orbiting very distant stars,” Beaulieu said.

    The sharp Hubble and Keck Observatory images allowed the research teams to separate out the background source star from its neighbors in the very crowded star field in the direction of our galaxy’s center. Although the Hubble images were taken 6.5 years after the lensing event, the source and lens star were still so close together on the sky that their images merged into what looked like an elongated stellar image.

    Astronomers can measure the brightness of both the source and planetary host stars from the elongated image. When combined with the information from the microlensing light curve, the lens brightness reveals the masses and orbital separation of the planet and its host star, as well as the distance of the planetary system from Earth. The foreground and background stars were observed in several different colors with Hubble’s Wide Field Camera 3 (WFC3), allowing independent confirmations of the mass and distance determinations.

    NASA Hubble WFC3
    WFC3

    The observations, taken with the Near Infrared Camera 2 (NIRC2) on the Keck 2 telescope more than eight years after the microlensing event, provided a precise measurement of the foreground and background stars’ relative motion.

    Keck NIRC2
    NIRC2

    “It is the first time we were able to completely resolve the source star and the lensing star after a microlensing event. This enabled us to discriminate between two models that fit the data of the microlensing light curve,” Batista said.

    The Hubble and Keck Observatory data are providing proof of concept for the primary method of exoplanet detection that will be used by NASA’s planned, space-based Wide-Field Infrared Survey Telescope (WFIRST), which will allow astronomers to determine the masses of planets found with microlensing.

    NASA WFIRST telescope
    WFIRST

    WFIRST will have Hubble’s sharpness to search for exoplanets using the microlensing technique. The telescope will be able to observe foreground, planetary host stars approaching the background source stars prior to the microlensing events, and receding from the background source stars after the microlensing events.

    “WFIRST will make measurements like we have made for OGLE-2005-BLG-169 for virtually all the planetary microlensing events it observes. We’ll know the masses and distances for the thousands of planets discovered by WFIRST,” Bennett explained.

    See the full article here.

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    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.
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  • richardmitnick 3:16 pm on July 30, 2015 Permalink | Reply
    Tags: Astronomy, ,   

    From Keck: “Keck Observatory Names Chief Scientist” 

    Keck Observatory

    Keck Observatory

    Keck Observatory

    July 30, 2015
    Steve Jefferson
    W. M. Keck Observatory
    sjefferson@keck.hawaii.edu
    808-881-3827

    1
    Anne L Kinney, Credit: NASA

    W. M. Keck Observatory is very pleased to announce Anne Kinney has been appointed Chief Scientist, effective August 3, 2015.

    “We are delighted to welcome Anne as the Chief Scientist of Keck Observatory,” said observatory Director, Hilton Lewis. “In this new role, she will be responsible for stewardship of the observatory’s scientific programs and for ensuring the health and vibrancy of the science conducted at this observatory.”

    Kinney comes to Keck Observatory from NASA, where she was most recently the Director of the Solar System Exploration Division at Goddard Space Flight Center. Kinney brings more than 30 years of scientific research and organizational leadership experience. She holds a PhD from New York University in Physics and Astronomy and is very familiar with Keck Observatory as she has been a member of the observatory’s Science Steering Committee since 2012.

    “It is my great pleasure to be joining the stellar Keck Observatory team,” Kinney said. “For me, one of the great attractions is the quality and dedication of its team. Keck Observatory’s international reputation speaks to the remarkable focus that the staff brings to extracting peak performance from two telescopes that are as beautiful as they are cutting edge.”

    Prior to her service at Goddard, Kinney was the Director of the Universe Division in the Science Mission Directorate at NASA Headquarters, with a portfolio including Hubble Space Telescope, Chandra X-ray Observatory, Spitzer Space Telescope, SOFIA, and Fermi.

    Kinney is an expert in extragalactic astronomy and has published 80 papers in refereed journals on quasars, blazars, active galaxies and normal galaxies, and signatures of accretion disks in active galaxies. She has demonstrated that accretion disks in the center of active galaxies lie at random angles relative to their host galaxies.

    Kinney received the Presidential Rank Award in 2012, has received two Exceptional Leadership Awards at NASA, and was a visiting scholar at the Institute of Astronomy in Cambridge.

    “I am thrilled that Anne has agreed to join us and contribute her energy and expertise to advance WMKO’s leadership in ground-based astronomy,” Lewis said.

    See the full article here.

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    Mission
    To advance the frontiers of astronomy and share our discoveries with the world.

    The W. M. Keck Observatory operates the largest, most scientifically productive telescopes on Earth. The two, 10-meter optical/infrared telescopes on the summit of Mauna Kea on the Island of Hawaii feature a suite of advanced instruments including imagers, multi-object spectrographs, high-resolution spectrographs, integral-field spectrometer and world-leading laser guide star adaptive optics systems. Keck Observatory is a private 501(c) 3 non-profit organization and a scientific partnership of the California Institute of Technology, the University of California and NASA.

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.
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  • richardmitnick 11:16 am on July 30, 2015 Permalink | Reply
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    From U Hawaii: “Robotically Discovering Earth’s Nearest Neighbors” 

    U Hawaii

    University of Hawaii

    July 30, 2015

    A team of astronomers using ground-based telescopes in Hawaii, California, and Arizona recently discovered a planetary system orbiting a nearby star that is only 54 light-years away. All three planets orbit their star at a distance closer than Mercury orbits the sun, completing their orbits in just 5, 15, and 24 days.

    Astronomers from the University of Hawaii at Manoa, the University of California, Berkeley, the University of California Observatories, and Tennessee State University found the planets using measurements from the Automated Planet Finder (APF) Telescope at Lick Observatory in California, the W. M. Keck Observatory on Maunakea, Hawaii, and the Automatic Photometric Telescope (APT) at Fairborn Observatory in Arizona.

    UC Observatories Lick APF
    UCO Lick APF

    Keck Observatory
    Keck Observatory Interior
    Keck

    U Arizona APT Fairborn
    APT at Fairborn

    The team discovered the new planets by detecting the wobble of the star HD 7924 as the planets orbited and pulled on the star gravitationally. APF and Keck Observatory traced out the planets’ orbits over many years using the Doppler technique that has successfully found hundreds of mostly larger planets orbiting nearby stars. APT made crucial measurements of the brightness of HD 7924 to assure the validity of the planet discoveries.

    1
    HD7924

    Artist’s impression of a view from the HD 7924 planetary system looking back toward our sun, which would be easily visible to the naked eye. Since HD 7924 is in our northern sky, an observer looking back at the sun would see objects like the Southern Cross and the Magellanic Clouds close to our sun in their sky. Art by Karen Teramura & BJ Fulton, UH IfA.

    The new APF facility offers a way to speed up the planet search. Planets can be discovered and their orbits traced much more quickly because APF is a dedicated facility that robotically searches for planets every clear night. Training computers to run the observatory all night, without human oversight, took years of effort by the University of California Observatories staff and graduate students on the discovery team.

    “We initially used APF like a regular telescope, staying up all night searching star to star. But the idea of letting a computer take the graveyard shift was more appealing after months of little sleep. So we wrote software to replace ourselves with a robot,” said University of Hawaii graduate student BJ Fulton.

    The Keck Observatory found the first evidence of planets orbiting HD 7924, discovering the innermost planet in 2009 using the HIRES instrument installed on the 10-meter Keck I telescope.

    Keck HIRES
    Keck HIRES

    This same combination was also used to find other super-Earths orbiting nearby stars in planet searches led by UH astronomer Andrew Howard and UC Berkeley Professor Geoffrey Marcy. It took five years of additional observations at Keck Observatory and the year-and-a-half campaign by the APF Telescope to find the two additional planets orbiting HD 7924.

    The Kepler Space Telescope has discovered thousands of extrasolar planets and demonstrated that they are common in our Milky Way galaxy.

    NASA Kepler Telescope
    Kepler

    However, nearly all of these planets are far from our solar system. Most nearby stars have not been thoroughly searched for the small “super-Earth” planets (larger than Earth but smaller than Neptune) that Kepler found in great abundance.

    This discovery shows the type of planetary system that astronomers expect to find around many nearby stars in the coming years. “The three planets are unlike anything in our solar system, with masses 7-8 times the mass of Earth and orbits that take them very close to their host star,” explains UC Berkeley graduate student Lauren Weiss.

    “This level of automation is a game-changer in astronomy,” says Howard. “It’s a bit like owning a driverless car that goes planet shopping.”

    Observations by APF, APT, and Keck Observatory helped verify the planets and rule out other explanations. “Starspots, like sunspots on the sun, can momentarily mimic the signatures of small planets. Repeated observations over many years allowed us to separate the starspot signals from the signatures of these new planets,” explains Evan Sinukoff, a UH graduate student who contributed to the discovery.

    The robotic observations of HD 7924 are the start of a systematic survey for super-Earth planets orbiting nearby stars. Fulton will lead this two-year search with the APF as part of his research for his doctoral dissertation. “When the survey is complete we will have a census of small planets orbiting sun-like stars within approximately 100 light-years of Earth,” says Fulton.

    Telescope automation is relatively new to astronomy, and UH astronomers are building two forefront facilities. Christoph Baranec built the Robo-AO observatory to takes high-resolution images using a laser to remove the blur of Earth’s atmosphere, and John Tonry is developing ATLAS, a robotic observatory that will hunt for killer asteroids.

    The paper presenting this work, “Three super-Earths orbiting HD 7924,” has been accepted for publication in the Astrophysical Journal and is available at no cost at http://arxiv.org/abs/1504.06629. The other authors of the paper are Howard Isaacson (UC Berkeley), Gregory Henry (TSU), and Bradford Holden and Robert I. Kibrick (UCO).

    n honor of the donations of Gloria and Ken Levy that helped facilitate the construction of the Levy spectrograph on APF and supported Lauren Weiss, the team has informally named the HD 7924 system the “Levy Planetary System.” The team also acknowledges the support of NASA, the U.S. Naval Observatory, and the University of California for its support of Lick Observatory.

    See the full article here.

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    System Overview

    The University of Hawai‘i System includes 10 campuses and dozens of educational, training and research centers across the Hawaiian Islands. As the public system of higher education in Hawai‘i, UH offers opportunities as unique and diverse as our Island home.

    The 10 UH campuses and educational centers on six Hawaiian Islands provide unique opportunities for both learning and recreation.

    UH is the State’s leading engine for economic growth and diversification, stimulating the local economy with jobs, research and skilled workers.

     
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