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  • richardmitnick 7:01 am on December 2, 2014 Permalink | Reply
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    From NYT: “New Images Refine View of Infant Universe” 

    New York Times

    The New York Times

    DEC. 1, 2014

    NYT Dennis Overbye
    Dennis Overbye

    In a throwback to another era in cosmic history, astronomers on Monday discussed the birth of the universe in a 15th-century palace, the Palazzo Costabili in Ferrara, Italy, where the amenities do not include Internet access.

    The subject of Planck 2014, as the meeting is called, is a new baby picture — and all of the accompanying vital statistics — of the universe when it was 380,000 years old and space was as hot as the surface of the sun. The portrait taker was the European Space Agency’s Planck satellite, which spent three years surveying a haze of microwave radiation left over from the last moments of the Big Bang with a bevy of sensitive radio receivers.

    Cosmic Background Radiation Planck
    CMB

    ESA Planck
    ESA/Planck

    The data will not be published until Dec. 22 in the journal Astronomy & Astrophysics, and the lack of Internet access frustrated astronomers who had planned on watching a webcast of the proceedings but found themselves relying on Twitter feeds instead.

    At least, they reported, the coffee was suitably strong.

    The new data largely confirms and refines the picture from a temperature map of the microwaves that Planck scientists, a multinational collaboration led by Jan Tauber of the European Space Agency, produced in 2013, showing the faint irregularities from which gargantuan features like galaxies would grow. Its microwave portrait reveals a universe 13.8 billion years old that is precisely mysterious, composed of 4.9 percent atomic matter, 26.6 percent mysterious dark matter that is not atomic, and 68.5 percent of even more mysterious dark energy, the glib name for whatever it is that seems to be blowing the universe apart.

    new
    A map of a patch of sky showing the temperature and polarization of cosmic microwaves from the end of the Big Bang, as reflected by dust swirling in the magnetic field of the Milky Way. Credit European Space Agency

    The result is a resounding victory for a sort of Standard Model of Cosmology that has grown up over the last two decades, said Lyman Page, a Princeton astrophysicist, in a phone call from Ferrara. “What we see is pretty impressive,” he said. “It’s amazing that just six parameters describe the universe.”

    Standard Model of Cosmology Inflation Lambda Model
    Lambda-CDM model

    Standard Model of Cosmology
    Another view

    Cosmologists still do not know what dark matter — the material that provides the gravitational scaffolding for galaxies — is, but the Planck results have increased their knowledge of what it is not, according to the French Center for National Scientific Research.

    Recently space experiments like NASA’s Fermi Gamma-ray Space Telescope and Alpha Magnetic Spectrometer have recorded excess cosmic ray emissions that, some say, could be evidence of a certain kind of dark matter particles colliding and annihilating one another.

    NASA Fermi Telescope
    NASA/Fermi

    NASA AMS02 device
    NASA/AMS-02

    After Planck, we need another answer for those experiments, the French agency concluded in a statement.

    Neal Weiner, a particle theorist at New York University, who is not part of Planck, concurred. That model of dark matter, he said in an email, if not completely excluded, now could be severely constrained. “If this holds up, at the very least a possibility to discover dark matter is now diminished.”

    Planck dealt a blow to another possible dark matter candidate, namely a brand of the ghostly particles known as neutrinos. Physicists have known of three types of neutrinos for some time and have wondered if there were any more, whose accumulated mass would affect the evolution of the universe. Planck’s results leave little room for a fourth kind, so-called sterile neutrinos.

    Compounding the frustration of cosmologists in the room in Ferrara and at large was an issue that has galvanized them for the better part of a year: whether astronomers had detected the very beginnings of the Big Bang in the form of space-time ripples known as gravitational waves.

    Gravitational Wave Background
    Gravitational Waves per BICEP2 radio telescope.

    BICEP 2
    BICEP 2 interior
    BICEP 2 with South Pole Telescope

    The added value of the new Planck data is a map showing how the microwaves are polarized, information that could shed light on what was going on when the universe was a trillionth of a trillionth of a trillionth of a second old, and in the grip of forces about which physicists can only speculate.

    Among the hottest topics of speculation these days is the idea — known as inflation — that the universe underwent a violent and brief surge of expansion in the earliest moments, settling the geometry and other aspects of the present universe. Such an explosion, theorists say, would have left faint corkscrew swirls, known technically as B-modes, in the pattern of polarization of the microwaves.

    In March there was much excitement when a team of American astronomers operating a radio telescope at the South Pole called Bicep2 announced they had detected such a pattern. Alan Guth of M.I.T., one of the inventors(?) [theorist would be better] of inflation, was at the news conference at Harvard announcing the results.

    Alan Guth
    Alan Guth

    After three months of spirited debate, the astronomers conceded, however, that their signal could have been caused by interstellar dust, which can also twist the microwaves.

    Enter Planck, which observed the microwaves in nine different frequencies, making it easy to distinguish dust. Bicep2 had only one frequency.

    A preliminary report from Planck in September confirmed that there was enough dust in Bicep2’s patch of sky to account for the twisting, but there are still large uncertainties that leave room for primordial gravitational waves.

    Subsequently, Planck and Bicep agreed to pool their data for a joint analysis.

    Planck scientists have meanwhile published their own polarization maps, which astronomers say will be useful for studying how the anti-gravitational push of dark energy and the gravitational pull of dark matter orchestrated the growth of galaxies and the universe when it was two or three billion years old — a sensitive age.

    The bumps in the microwave maps that eventually grow to galaxies amount to a temperature difference of only about 75-millionths of a Kelvin, in an otherwise uniform hiss. To measure polarization, radio astronomers have to discern temperature differences about a tenth of that.

    The difficulty of doing this research, while the world looks on, can be gauged by the number of missed deadlines. Planck researchers originally hoped to have their polarization studies done this summer. Recently they had set November as their deadline, aiming to present the results at this conference in Ferrara. Likewise, the joint Bicep/Planck paper is now expected this month or in January.

    Asked about this, David Spergel, a Princeton cosmologist and veteran of cosmic microwave studies who had spent the day fielding Twitter messages from Ferrara, said he had adopted an acronym often used by NASA in announcing launch dates: NET, meaning “No Earlier Than.”

    See the full article here.

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  • richardmitnick 5:37 am on November 6, 2014 Permalink | Reply
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    From NYT: “Funding Is Restored for Storied California Observatory” 

    New York Times

    The New York Times

    NOV. 5, 2014

    NYT Dennis Overbye
    DENNIS OVERBYE

    A year after the University of California announced that it would phase out all funding for its storied Lick Observatory, sparking fears that the observatory could close if it could not find outside support, the university said on Tuesday that it had changed its mind.

    As Aimée Dorr, provost and executive vice president of the university, and Nathan Brostrom, executive vice president, said in an Oct. 29 letter to the acting director of the observatory, Claire Max of the University of California, Santa Cruz, “We are rescinding our previous requirements that Lick Observatory become self supporting.”

    Lick, which started operations in 1888, is the oldest mountaintop observatory in the West, located on Mount Hamilton, about 30 miles south of San Francisco. In recent years it has played a pivotal role in the discovery of dark energy, which resulted in a Nobel Prize in 2011, and of planets around other stars.

    UCO Lick Shane Telescope
    UCO Lick Shane Telescope interior
    UCO Lick Shane Telescope

    Lick costs the university about $1.3 million a year to operate, money that the university said was needed in a time of declining state support for new ventures like the mighty Keck telescopes it owns with Caltech on Mauna Kea in Hawaii and the even mightier Thirty Meter Telescope, an international project under construction on Mauna Kea.

    Keck Observatory
    Keck Observatory Interior
    Keck

    TMT
    TMT Schematic
    TMT

    Acknowledging widespread interest among astronomers in keeping Lick alive, Provost Dorr and Mr. Brostrom wrote that they had never said they intended to close Lick and that recent budget plans suggested it could continue to operate without wrecking other projects.

    “Indeed,” they wrote, “we see the Lick, Keck and Thirty Meter Telescope Observatories as an integrated ecosystem that can together maintain and grow U.C.’s leadership in astronomy.”

    See the full article here.

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  • richardmitnick 5:10 pm on October 8, 2014 Permalink | Reply
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    From Dennis Overbye at the New York Times: “How to Make a Black Hole” 

    New York Times

    The New York Times

    On July 2, 1967, a network of satellites designed to detect tests of nuclear weapons recorded a flash of gamma rays coming from the wrong direction — outer space.

    And so it was that human astronomers were tipped to the existence of one of the most violent phenomena of nature. Today, they know that about once a day somewhere in the observable universe, an explosion called a gamma-ray burst occurs, releasing more energy in a few seconds than our galaxy does in a year.

    These magnificent cosmic conflagrations are as far away as they are rare, which is just as well. If one happened nearby, in our own galaxy, we could be swathed with radiation. The closest gamma-ray burst whose distance has been measured happened some 119 million light-years from us, far outside the so-called Local Group, which contains our own Milky Way galaxy. The farthest so far recorded is now 31 billion light-years away, as calculated by the mathematics of the expanding universe; it happened when the universe was only 500 million years old.

    local group
    Local Group

    Gamma-ray bursts are thought to be the final step in the series of transformations by which stars shrink and slump from blazing glory to oblivion, winding up as bottomless deadly dimples in the fabric of space-time — that is to say, as black holes.

    The hierarchy of dead stars goes like this: Stars like the sun, when they run out of thermonuclear fuel, shrink to cinders known as white dwarfs, the size of Earth. Stars more massive than the sun might collapse more drastically and undergo a supernova explosion, blasting newly formed heavy elements into space to enrich future stars, planets and perhaps life, and leaving behind crushed cores known as neutron stars. These weigh slightly more than the sun but are only 12 miles or so in diameter — so dense that a teaspoonful on Earth would weigh as much as Mount Everest.

    Such an explosion, bright enough to be seen in daylight, happened in 1054, Earth time, as told by Chinese astronomers and the ancient inhabitants of Chaco Canyon in what is now New Mexico. That supernova left behind the Crab nebula, a tangle of glowing shreds of gas and a pulsar — a magnetized neutron star spinning 30 times a second, whipping the gas with magnetic fields that make it glow.

    Crab
    Crab Nebula

    Neutron stars, theorists say, are the densest stable form of matter, but they are not the end of the story. According to theory, too much mass accumulating on a neutron star can cause its collapse into a black hole, an abyss from which not even light can escape. The signature of such a cataclysm would be a gamma-ray burst, astronomers say.

    col
    Colliding neutron stars

    Supercomputer simulations by astronomers led by Luciano Rezzolla of the Institute of Theoretical Physics in Frankfurt have recently showed this would work.

    The simulation, as it unwound over six weeks of supercomputer time at the Max Planck Institute for Gravitational Physics, started with two neutron stars orbiting each other at a distance of 11 miles. That would not be unusual in the universe; most stars are in fact part of double-star systems and several pairs of pulsars orbiting each other are already known. They will eventually collide because such dense, heavy objects lose energy rapidly and spiral together.

    In the case of Dr. Rezzolla’s computation, it took seven milliseconds for tidal forces from the larger star’s gravity to rip apart the smaller star and unwind it into a spiral resembling flaming toothpaste writhing with magnetic fields and begin munching up the gas.

    The excess plasma forms a fat disk around the new black hole, and its magnetic fields, a billion times stronger than those in the sun, align to channel beams of radiation and particles out at the speed of light. The result is a gamma-ray burst visible across the universe, carrying the news of doom — the last astronomers will ever hear of these stars.

    For those two stars, the last bang was the best. Oblivion can be such a lovely sight.

    See the full article here.

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  • richardmitnick 12:46 pm on September 3, 2014 Permalink | Reply
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    From Dennis Overbye at The New York Times: “The V838 Monocerotis Star Still Has Astronomers’ Heads Exploding” 

    New York Times

    The New York Times

    SEPT. 3, 2014
    Dennis Overbye

    For astronomers and aficionados of cosmic violence, an obscure star known as V838 Monocerotis has turned out to be a gift that has kept on giving for a long, long time.

    http://upload.wikimedia.org/wikipedia/commons/thumb/d/d3/V838_Mon_HST.jpg/600px-V838_Mon_HST.jpg838
    In January 2002, a dull star in an obscure constellation suddenly became 600,000 times more luminous than our Sun, temporarily making it the brightest star in our Milky Way galaxy. The mysterious star, called V838 Monocerotis, has long since faded back to obscurity. But observations by NASA’s Hubble Space Telescope of a phenomenon called a “light echo” around the star have uncovered remarkable new features. These details promise to provide astronomers with a CAT-scan-like probe of the three-dimensional structure of shells of dust surrounding an aging star.

    NASA Hubble Telescope
    NASA/ESA Hubble

    The star forms part of the shoulder of an imagined unicorn in the constellation Monoceros, 20,000 light-years away, and in January 2002, astronomers saw it blow up. Over the next few months, it became a million times as luminous as the sun and swelled in diameter to a billion miles, comparable to the orbit of Jupiter. It was briefly one of the most luminous stars in the galaxy.

    Astronomers are still arguing and speculating about what happened. Measurements of the star’s light output showed that the explosion happened in three stages, flaring and then dimming three times from January to March 2002.

    Some scientists have suggested that V 838 swallowed planets in its orbit. Others have proposed that V 838 was actually two stars orbiting each other, and that the explosions were a result of their atmospheres merging into a common envelope of gas.

    The answer could be relevant to our plight. Someday, a few billion years from now, the sun will run out of fuel and become a red giant,swallowing Mercury and frying the Earth and Venus.

    Whatever it was that made V 838 erupt, astronomers are still watching it go.

    The star, it turns out, is embedded in a cloud of dust trillions of miles across. Most likely, astronomers say, these wreaths of dust gave rise to V 838 perhaps four million years ago. They would usually be invisible, but the pulses of light traveling outward from the explosion have illuminated shells of dust previously kicked off the star. The Hubble Space Telescope has recorded images of these so-called light echoes, and viewing them in succession calls to mind the explosion of Darth Vader’s Death Star — except that in this case, nothing is moving but the outward-rushing light wave; the dust is standing still.

    As a result, the death of V 838 Monocerotis is giving astronomers a rare look at the circumstances that gave it birth. Dust to dust and ashes to ashes. So it goes.

    Nothing lasts forever, but in the universe, nothing is ever really gone, either. As the Columbia University astrophysicist Caleb Scharf pointed out in an essay on his blog recently, long after you and I are dead, the light reflected off our faces today will still be traveling across space, ever fainter with distance, but always there. For somebody with a big enough telescope somewhere, we will be immortal.

    See the full article here.

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  • richardmitnick 4:43 pm on July 21, 2014 Permalink | Reply
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    From The New York Times: “More Eyes on the Skies” 

    New York Times

    The New York Times

    JULY 21, 2014

    do
    DENNIS OVERBYE

    The future, it is often said, belongs to those who plan for it. And astronomers have been busy working the proverbial smoke-filled rooms (or whatever passes for them today) where the destiny of big science is often shaped and crisscrossing one another in airports on fund-raising trips. Now they are about to have something to show for it.

    More than a decade after competing groups set out to raise money for gargantuan telescopes that could study planets around distant stars and tune into the birth of galaxies at the dawn of time, shovels, pickaxes and more sophisticated tools are now about to go to work on mountaintops in Hawaii and Chile in what is going to be the greatest, most expensive and ambitious spree of telescope-making in the history of astronomy.

    If it all plays out as expected and budgeted, astronomers of the 2020s will be swimming in petabytes of data streaming from space and the ground. Herewith a report card on the future of big-time stargazing.

    On June 20, officials from the European Southern Observatory blew the top off a mountain in northern Chile called Armazones, breaking ground for what is planned to be the largest, most powerful optical telescope ever built. Known as the European Extremely Large Telescope, or E-ELT, it will have a segmented mirror 39 meters (about 128 feet) in diameter, powerful enough to see planets around distant stars. By comparison, the largest telescopes now operating are 10 meters in diameter.

    ESO E-ELT
    ESO’s E-ELT

    ESO VLT Interferometer
    The European Southern Observatory consortium’s Very Large Telescope array, in Chile, is made up of four eight-meter telescopes. Credit European Southern Observatory

    The European Southern Observatory is a consortium of 14 European nations and Brazil, which has agreed to join but is still waiting for its Parliament to ratify the move. Brazil’s official entrance would put the group more than 90 percent of the way toward the $1.5 billion in 2012 dollars the telescope is projected to cost, enough to begin big-ticket items like a dome, said Lars Christensen, a spokesman for the consortium.

    The telescope should be ready on June 19, 2024. “We’ll all be back here,” said Tim de Zeeuw, the group’s director general, at the groundbreaking.

    That’s not the only mega telescope project out there. Two years ago, another group of astronomers blasted away the top of another mountain in Chile, Las Campanas, where they plan to build the Giant Magellan Telescope.

    Giant Magellan Telescope
    Giant Magellan Telescope

    That telescope will have at its heart a set of seven eight-meter mirrors ganged together to make the equivalent of a mirror 25 meters in diameter. Three of those mirrors have been cast and polished at the University of Arizona, one of nine institutions that make up the Giant Magellan organization. A fourth mirror is on order for next year.

    Giant Magellan
    Australia Astronomy Limited
    Australian National University
    Carnegie Institution for Science
    Harvard University
    Korean Astronomy and Space Science Institute
    Harvard-Smithsonian Center for Astrophysics
    Texas A&M University
    University of Arizona
    University of Chicago
    University of Texas at Austin

    Wendy Freedman, the director of the Carnegie Observatories, one of the spearheads of the Magellan collaboration, said by email that members were now in the final phases of forming a limited liability corporation, the legal and financial entity that will build and own the telescope. To date, the group has raised about $500 million of the $880 million (2012 dollars) needed for their telescope.

    She expects construction to begin later this year. “Our plan is to be on the air with the first four mirrors taking early science data in 2021,” she said. “So things are continuing to go very well.”

    In Hawaii, there will be no blasting needed, just some grading with a bulldozer, on Mauna Kea, where yet another group of astronomers plans to build a telescope 30 meters in diameter — the simply named Thirty Meter Telescope — on a plateau just below the nearly 14,000-foot summit. Mauna Kea, the highest peak in the Pacific, is already home to 12 telescopes, including the twin 10-meter telescopes at the Keck observatory and a pair of eight-meters, making it the busiest mountain in astronomy.

    Thirty Meter Telescope
    Thirty Meter Telescope

    Thirty Meter Telescope
    Association of Canadian Universities for Research in Astronomy
    California Institute of Technology
    Department of Science and Technology of India
    National Astronomical Observatories of the Chinese Academy of Sciences
    National Astronomical Observatory of Japan
    University of California

    It is also a sacred place for Hawaiians, many of whose ancestors have been buried up there. As a result, it’s not so easy gaining permission to add yet another telescope, said Michael Bolte of the University of California, Santa Cruz, a co-director of the project, an international collaboration led by Caltech and the University of California and now doing business as Thirty Meter Telescope International Observatory LLC.

    A billion-dollar telescope capable of outperforming Hubble can’t be built by a backyard stargazer or even a single university. The Thirty Meter Telescope in Hawaii and the Giant Magellan in Chile, both now on the verge of construction, are the products of international teams that have pursued their dreams even through a global recession.

    “I think we’re finally free and clear to build on that site,” Dr. Bolte said in an interview, saying they had chosen an unobtrusive spot for the telescope. He expects to begin grading a road to the site this summer as soon as the project clears its last hurdle with the Hawaiian authorities.

    The Thirty Meter Telescope will cost $1.2 billion in those same 2012 dollars. By early next year, when India and Canada are expected to become full members of the corporation, Dr. Bolte said, they will have 85 percent of the money needed; they are still looking for more partners. A grand groundbreaking ceremony is being scheduled for Oct. 7.

    “It’s a crazy science,” Dr. Bolte said, ticking off the names of historical benefactors of astronomy and telescope financiers, “that facilities at the forefront tend to be built with private money,” something that rarely happens in, say, physics.

    Big Mirrors, Big Views

    The view from these new telescopes, astronomers say, should be spectacular.

    A telescope’s ability to gather light is determined by the area of its primary mirror. For a long time, the five-meter Hale reflector on Palomar Mountain, in San Diego County, was considered the practical earthly limit, but in the 1980s, astronomers devised ways to build bigger, thinner, mirrors that would not sag, leading to a bevy of eight-meter mirrors as well as the two 10-meter Kecks. The Magellan, the smallest of the new breed, however, will be six times as powerful as the Kecks in scooping up distant dim starlight; the others will be even more powerful.

    Caltech Hale Telescope at Palomar
    Hale Telescope

    Keck Observatory
    Keck Observatory

    The Hubble Space Telescope is only 94 inches, about 2.4 meters in diameter. It gains its power not from size but from being above the atmosphere, which blurs and filters the light from stars.

    NASA Hubble Telescope
    NASA/ESA Hubble

    Increasing their powers even more, the new telescopes will be equipped with a technology that did not exist the last time around: adaptive optics [in use since the 1990’s], the ability to adjust the shape of the mirrors to minimize or cancel the effects of the atmospheric turbulence that causes stars to twinkle. The result, astronomers say, is that these telescopes will be able to detect fainter objects than Hubble can, like planets or bits of galaxies coming together, and more clearly.

    A Boom in Chile

    The inauguration of these new telescopes, early in the next decade, will further enshrine the Atacama Desert in Chile, which is bone-dry, high, dark and blessed with remarkably steady air, as the center of world astronomy. The region already is home to, among other observatories, the Atacama Large Millimeter/sub-millimeter Array, or ALMA, an international project that is the world’s most expensive radio telescope, and the European Southern Observatory’s Very Large Telescope, an array of four eight-meter telescopes near the site of the coming Extremely Large Telescope.

    ALMA Array
    ALMA

    The whole neighborhood, in fact, is booming. But for red tape, construction was also supposed to have started this month on the Large Synoptic Survey Telescope on Pachón Mountain, in, yes, Chile.

    LSST Telescope
    LSST

    That telescope, a joint project of the National Science Foundation and the Department of Energy, is eight meters in diameter. That mountain was dynamited back in 2011. The project director, Steve Kahn of Stanford, said that a news release was already written and waiting for the moment when the project, officially the LSST Corporation, receives formal approval from the National Science Foundation to start spending money.

    “I am sure we will get started officially soon, but unfortunately, this process isn’t over until it is over,” Dr. Kahn wrote in an email.

    A ceremony for laying the “first stone” is planned for next spring in Chile, he said.

    The National Science Foundation has budgeted $473 million to build the telescope. The Energy Department is kicking in $165 million for a 3,200-megapixel camera, which will produce an image of the entire sky every few days and over 10 years will produce a movie of the universe, swamping astronomers with data that will enable them to spot everything that moves or blinks in the heavens, including asteroids and supernova explosions.

    Among the Stars

    What about outer space, where the stars actually are?

    It was front-page news two years ago when the National Reconnaissance Office, which operates spy satellites, gave NASA two space telescopes the same size and design as a Hubble that had been sitting in a warehouse. Some astronomers, notably the former astronaut and Hubble repairman John M. Grunsfeld, NASA’s associate administrator for science mission, suggested that one of these could be used to jump-start a mission to study dark energy.

    The National Academy of Sciences had ranked that mission atop the to-do list for this decade, but it was ambushed by the rising cost of NASA’s James Webb Space Telescope (more on that later).

    NASA Webb Telescope
    NASA/Webb

    A committee from the academy has recently endorsed the idea of using the spy telescope, which is 2.4 meters in diameter, for the mission, instead of the originally envisioned one-meter telescope. The academy agreed that the bigger telescope would enhance the scientific returns of the mission, now known as Wfirst-AFTA, for Wide Field Infrared Survey Telescope-Astrophysics Focused Telescope Assets, but warned that it could increase the cost and complexity. Congress directed NASA to spend $56 million on the mission in the last fiscal year, 2014, and the proposed budget for 2015 includes about $14 million.

    NASA WFIRST telescope
    NASA/WFIRST

    If this keeps up, said David Spergel, an astronomer at Princeton who is involved with the academy and the telescope, the mission could start as early as 2023, near the time the European Space Agency will send up its own dark energy probe, known as Euclid. By then, he said, the mission’s name would probably be less of a mouthful. “The good thing about Wfirst-AFTA,” Dr. Spergel wrote in an email, “is that there is no way that we will keep that name.”

    ESA Euclid
    ESA/Euclid

    Among the possibilities that NASA is studying closely is adding a coronagraph to the telescope [WFIRST]. Coronagraphs are basically opaque disks that were invented to black the intense light from the sun so astronomers could study the feathery faint corona of hot gases streaming outward from it. Exoplanet hunters are eager to deploy them to look for planets around distant stars. Getting a coronagraph on the dark energy telescope would be a valuable step toward a future mission, once known as the Terrestrial Planet Finder and now known by the placeholder name of New Worlds Telescope, long a dream of exoplanet hunters, that would be able to study Earthlike planets for signs of habitability, weather and life.

    And then there is the most expensive and high-flying “big eye” of all, NASA’s James Webb Space Telescope, which Nature magazine once called “the telescope that ate astronomy.” Named for a former administrator of NASA, it is the successor to Hubble (which is still going strong, thank you), but is almost three times its size, with a 6.5-meter-diameter mirror that will have to fold out like a flower in orbit.

    The Webb telescope was supposed to be launched this year, but was late and burned past its $5 billion budget like one of NASA’s rockets, devouring money that could have gone toward other projects. The House Appropriations Committee once voted to cancel it, but the project was reinstated with a budget cap of $8 billion and a launch date of 2018.

    Since then, no news has basically been good news for Webb. It is still on track for 2018, NASA says. In July the agency reported that it had finished testing the framework that will hold the leaves of the telescope mirror and scientific instruments in place.

    Heat and Light

    The Webb telescope was built to study the first stars and galaxies that emerged in the hundred million years or so after the Big Bang, a missing period in cosmic history. It is therefore designed to record infrared radiation rather than visible light because objects at that distance and vintage are flying away from us so fast, by the rules of the expanding universe, that their light has been “redshifted” to longer wavelengths.

    As it happens, infrared, or heat radiation, is an excellent way to study planets, which tend to emit more heat than light. Astronomers have long hoped that spectroscopic observations of an exoplanet atmosphere might reveal the signatures of life, such as oxygen or chlorophyll.

    Recently, some astronomers have suggested they might even be able to see industrial pollution as well, in particular chlorofluorocarbons, the greenhouse gases that also destroy ozone. Over a few millenniums of industry, the thinking goes, some of these gases could build up to levels detectable from far away and stay that way for 50,000 years.

    It would be ominous, however, Henry W. Lin, a student at Harvard, and his colleagues wrote in a paper submitted to The Monthly Notices of the Royal Astronomical Society, if astronomers see the markers of pollution around some distant planet but no indications of present life. That detection, they wrote, “might serve as an additional warning to the ‘intelligent’ life here on Earth about the risks of industrial pollution.” The future belongs to those who plan and care for it.

    Last but hardly least is the Hubble Space Telescope, which has been providing humanity with matchless cosmic postcards from its perch above the sky ever since it was launched in 1990 and first fixed in 1993. Hubble was last visited and serviced by astronauts — presumably for the final time — in 2009. Matt Mountain, the director of the Space Telescope Science Institute, reports that it is doing well. A recent NASA review concluded, he said in an email, that “Hubble is operating at or near the highest level of performance and scientific productivity in its history.”

    Recent estimates of its orbit suggest that it will re-enter Earth’s atmosphere no earlier than 2027 and may probably stay up well into the 2030s. Its main instruments are likely to still be working in 2020. That means the Hubble will still be operational when the Webb telescope goes up in 2018.

    “It looks like it,” Dr. Mountain said. “We are certainly setting our planning that way.”

    See the full article here.

    [The condition of Hubble not withstanding, any cancellation of Webb would be about as stupid and wrong headed as was the cancellation of the Superconducting_Super_Collider by the idiots in our Congress in 1993. Look where that got us: jobs as the hand maidens of the European Organization for Nuclear Research, CERN, which built the Large Hadron Collider and found what Fermilab’s Tevatron had searched a very long time to find, the Higgs boson. We could just cede space to the ESA for spacecraft and sit with our large collection of ground based monsters.]


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  • richardmitnick 11:17 am on July 16, 2014 Permalink | Reply
    Tags: , , , , Dennis Overbye, , Universe   

    From The New York Times: "Stalking the Shadow Universe" 

    New York Times

    JULY 16, 2014
    DENNIS OVERBYE

    For centuries people have found meaning — or thought they did — in what they could see in the sky, the shapes of the constellations echoing old myths, the sudden feathery intrusion of comets, the regular dances of the planets, the chains of galaxies, spanning unfathomable distances of time and space.

    Universe

    Since the 1980s, however, astronomers have been forced to confront the possibility that most of the universe is invisible, and that all the glittering chains of galaxies are no more substantial, no more reliable guides to physical reality, than greasepaint on the face of a clown.

    The brute mathematical truth is that atoms, the stuff of stars, you and me, make up only 5 percent of the universe by weight. A quarter of it is made of mysterious particles known as dark matter, and the remaining 70 percent a mysterious form of energy called dark energy. Physicists theorize that dark matter could be exotic particles left over from the Big Bang. They don’t know what it is, but they can deduce that dark matter is there by its gravitational effect on the things they can see. If [Isaac] Newton’s laws of gravity held over cosmic distances, huge amounts of more matter than we can see were needed to provide the gravitational glue to keep clusters of galaxies from flying apart, and to keep the stars swirling around in galaxies at high speed.

    Cosmologists have theorized that it is in fact dark matter, slowly congealing under its own weight into vast clouds, that provides the scaffolding for stars and galaxies.

    To strip the greasepaint from cosmic history, astronomers have performed computer simulations of how dark matter would evolve from a nearly uniform cloud into the filaments and clumps characteristic of the arrangement of galaxies today in the luminous universe. A multinational group led by Mark Vogelsberger of the Massachusetts Institute of Technology has recently performed one of the most detailed of these studies yet, a calculation called Illustris.

    Their model sought to take into account not just the gravity of dark matter particles pulling atoms and one another around, but the electromagnetic and nuclear interactions between atoms — so-called gastrophysics — like the formation and explosion of stars.

    The result, they said, is the closest match yet between dark matter models and the distribution and types of galaxies in the visible universe.

    Meanwhile, astronomers at the California Institute of Technology have begun to be able to illuminate and map the weblike structure of the dark matter in space using an instrument they call the Cosmic Web Imager on the 200-inch telescope at Palomar Observatory. The imager in effect uses bright galaxies and quasars as a kind of flashlight to light up the sparse atoms strewn along with the dark matter in space, confirming the tendril structure predicted by the computer simulations.

    Caltech Cosmic Web Imager
    Cosmic Web Imager

    Caltech Palomar Observatory
    Palomar Observatory – Caltech

    qua
    Quasar

    More evidence of the power of the dark side.


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  • richardmitnick 5:14 am on May 13, 2014 Permalink | Reply
    Tags: , , , Dennis Overbye, Geof Marcy,   

    From Dennis Overbye at The New York Times: “Geoffrey W. Marcy – Finder of New Worlds 

    New York Times

    NY Times Dennis Overbye
    Dennis Overbye

    This is copyright protected, so just a few notes to wet your whistle

    May 13, 2014
    Last summer a homely room in the basement of a math building on the University of California campus here was ground zero in the epic quest to end cosmic loneliness.

    An area rug with geometric shapes and yellow rings suggestive of planetary orbits covered the floor. A photograph of the Milky Way rising over the Hawaiian volcano Mauna Kea hung on one wall. A Naugahyde couch ran along one side of the room. Opposite it was a small refrigerator with a stash of Grape-Nuts and soy milk.

    The nearest bathroom was two sets of password-protected security doors away.

    This is the lair of Geoffrey W. Marcy, holder of the Watson and Marilyn Alberts Chair in the Search for Extraterrestrial Intelligence and, outside a certain robot spacecraft named Kepler, the most prolific American discoverer of alien worlds, so-called exoplanets circling stars beyond the sun.

    Geof Marcy

    An August evening found Dr. Marcy, a gray-goateed, twinkly-eyed presence with an aggressively empathetic air, crouched as usual in a corner in an old wooden desk chair. In front of him were computer screens and a video display connecting him to Mauna Kea, home of the twin Keck telescopes, at 40 feet in diameter the two largest in the world.

    See the full article here.

    From Geof Marcy’s web site

    Research projects:

    Dr. Marcy is a leading astrophysicist in the detection and characterization of exoplanets. He and collaborators have discovered over 250 extrasolar planets, allowing ongoing study of their masses, radii, and orbits, including eccentricities and misalignments. His research team discovered the first multiple planet system (Upsilon Andromedae), the first saturn-sized planet, and the first Neptune-size planet. He is a co-investigator with the NASA Kepler mission that recently announced 1230 exoplanets, most being smaller than twice the size of Earth. Kepler-10b has a radius only 1.4 times that of Earth. His current research focuses on finding other Earth-size planets and solar systems similar to our own. Ongoing work is designed to study the sizes, occurrence frequency, chemical composition, and the orbits of Earth-size planets.
    Biography:

    Dr. Marcy is a Professor of Astronomy at UC Berkeley and an Adjunct Professor of Physics and Astronomy at San Francisco State University. He is the Director of Berkeley’s “Center for Integrative Planetary Science”, a research unit designed to study the formation, geophysics, chemistry and evolution of planets. He is an elected member of the National Academy of Sciences and has been the recipient of numerous awards, including the NASA Medal for Exceptional Scientific Achievement. He was named Discovery Magazine’s Space Scientist of the Year in 2003. He was also co-recipient of the prestigious Shaw Prize.


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  • richardmitnick 9:06 pm on August 16, 2013 Permalink | Reply
    Tags: , , , , Dennis Overbye, , ,   

    Dennis Overbye Makes Page 3 on a Friday – Kepler is Hobbled 

    New York Times

    This is copyright protected, so just some hints.

    NASA Planet-Hunting Star Idled by Broken Parts

    Friday, August 16, 2013
    Dennis Overbye

    NASA said Thursday that its celebrated planet-hunting Kepler spacecraft, which broke down in May when a reaction wheel that controls its pointing failed, could not be fixed and would never again search for planets around other stars.

    kepler
    Kepler

    The disappointing news brings to an end, for now, one phase of the most romantic of space dreams, the search for other Earths among the exoplanets of the Milky Way. NASA has already asked astronomers for ideas on how to use the hobbled spacecraft, whose telescope is in perfect shape.

    At last count, Kepler had discovered 3,548 possible planets, and 135 of them — some smaller than the Earth — have been validated by other observations, including earthbound telescopes. But hundreds or thousands more are in the pipeline, said William Borucki of NASA’s Ames Research Laboratory in Mountain View, Calif., Kepler’s originator and principal investigator.

    The closest Kepler has come to finding another Earth was in April, when the team discovered a pair of planets about half again as big as the Earth orbiting a yellow star, now known as Kepler 62, that is 1,200 light years away. Both planets reside in the “Goldilocks” zone where temperatures should be lukewarm and suitable for liquid water and thus life as we imagine it.”

    62
    Kepler-62f (foreground) and Kepler-62e (right) are habitable zone exoplanets orbiting the star Kepler-62 (center). (Artists’ conception.) Credit: NASA Ames/JPL-Caltech

    See the full article here.

    NASA

    NASA Ames Research Center

    NASA Goddard Banner


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  • richardmitnick 6:57 pm on August 13, 2013 Permalink | Reply
    Tags: , , , , , Dennis Overbye,   

    From The New York Times: “A Black Hole Mystery Wrapped in a Firewall Paradox” 

    New York Times

    This is copyright protected, so, just a glimpse.

    August 12, 2013
    DENNIS OVERBYE

    “A high-octane debate has broken out among the world’s physicists about what would happen if you jumped into a black hole, a fearsome gravitational monster that can swallow matter, energy and even light. You would die, of course, but how? Crushed smaller than a dust mote by monstrous gravity, as astronomers and science fiction writers have been telling us for decades? Or flash-fried by a firewall of energy, as an alarming new calculation seems to indicate?

    ‘I was a yo-yo on this,’ said one of the more prolific authors in the field, Leonard Susskind of Stanford. He paused and added, ‘I haven’t changed my mind in a few months now.’

    Stephen Hawking, the British cosmologist, stunned the world by showing that when the paradoxical quantum laws that describe subatomic behavior were taken into account, black holes would leak particles and radiation, and in fact eventually explode, although for a hole the mass of a star it would take longer than the age of the universe. It was front-page news in 2004 when Dr. Hawking finally said that he had been wrong, and paid off a bet.

    bh

    Now, however, some physicists say that Dr. Hawking might have conceded too soon. ‘He had good reason,’ said Dr. Polchinski, ‘but he gave up for the wrong reason.’ Nobody, he explained, had yet figured out exactly how information does get out of a black hole.

    That was the task that four researchers based in Santa Barbara — Ahmed Almheiri, Donald Marolf, and James Sully, all from the University of California, Santa Barbara, and Dr. Polchinski of the Kavli Institute set themselves a year ago. The team (called AMPS, after their initials) found, to their surprise, that following the known laws of physics would lead to a contradiction, the firewall paradox.”

    O.K., so much for a glimpse. See the full article here.

    [I had one comment on this article. No where did I see any mention of the “Black Hole War”, between Dr. Susskind and Dr. Hawking, or any mention of Dr. Susskind’s book of the same name.]

     
  • richardmitnick 6:22 am on March 5, 2013 Permalink | Reply
    Tags: , , Dennis Overbye, , ,   

    Higgs in the New York Times From Dennis Overbye 

    New York Times

    If you are a fan of the search for Higgs, then you simply must get today’s New York Times and read Dennis Overbye in the Science section.

    Chasing the Higgs

    Particle Physicists in U.S. Worry About Being Left Behind

    All Signs Point to Higgs, but Scientific Certainty Is a Waiting Game

    Glossary: A Guide for the Perplexed

    Read On: Books About the Higgs

    higgs
    Higgs result at CMS

     
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