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  • richardmitnick 1:56 pm on January 16, 2017 Permalink | Reply
    Tags: , , FO Aquarii, , Sarah L. Krizmanich Telescope   

    From Notre Dame: “Notre Dame astrophysicists discover dimming of binary star’ 

    Notre Dame bloc

    Notre Dame University

    January 16, 2017
    Brian Wallheimer

    A team of University of Notre Dame astrophysicists led by Peter Garnavich, professor of physics, has observed the unexplained fading of an interacting binary star, one of the first discoveries using the University’s Sarah L. Krizmanich Telescope.

    Notre Dame Rooftop Sarah L Krizmanich  Telescope
    Notre Dame Rooftop Sarah L Krizmanich  Telescope Interior
    Notre Dame Rooftop Sarah L Krizmanich Telescope

    The binary star, FO Aquarii, located in the Milky Way galaxy and Aquarius constellation about 500 light-years from Earth, consists of a white dwarf and a companion star donating gas to the compact dwarf, a type of binary system known as an intermediate polar. The system is bright enough to be observed with small telescopes. Garnavich and his team started studying FO Aquarii, known as “king of the intermediate polars,” a few years ago when NASA’s Kepler Telescope was pointed toward it for three months. The star rotates every 20 minutes, and Garnavich wanted to investigate whether the period was changing.

    “I asked Erin Aadland, an REU student, to precisely measure the spin rate of a white dwarf. Does it speed up or slow down?” he said. “We can do that by looking at the interval between flashes from the star just like we use the ticks in a clock to tell time. The star turned out to have other plans for the summer.”

    Intermediate polars are interesting binary systems because the low-density star drops gas toward the compact dwarf, which catches the matter using its strong magnetic field and funnels it to the surface, a process called accretion. The gas emits X-rays and optical light as it falls, and we see regular light variations as the stars orbit and spin. Graduate student Mark Kennedy studied the light variations in detail during the three months the Kepler Space Telescope was pointing at FO Aquarii in 2014. Kennedy is a Naughton Fellow from University College, Cork, in Ireland who spent a year and a half working at Notre Dame on interacting binary stars. “Kepler observed FO Aquarii every minute for three months, and Mark’s analysis of the data made us think we knew all we could know about this star,” Garnavich said.

    Once Kepler was pointed in a new direction, Garnavich and his group used the Krizmanich Telescope to continue the study.

    “Just after the star came around the sun last year, we started looking at it through the Krizmanich Telescope, and we were shocked to see it was seven times fainter than it had ever been before,” said Colin Littlefield, a member of the Garnavich lab. “The dimming is a sign that the donating star stopped sending matter to the compact dwarf, and it’s unclear why. Although the star is becoming brighter again, the recovery to normal brightness has been slow, taking over six months to get back to where it was when Kepler observed.”

    “Normally, the light that we’d see would come from the accretion energy, and it got a lot weaker when the gas flow stopped. We are now following the recovery over months,” Garnavich said.

    One theory is that a star spot, a cool region on the companion, rotated into just the right position to disrupt the flow of hydrogen from the donating star. But that doesn’t explain why the star hasn’t then recovered as quickly as it dimmed.

    Garnavich and his team also found that the light variations of FO Aquarii became very complex during its low state. The low gas transfer rate had meant the dominant, 20-minute signal had faded and allowed other periods to show up. Instead of a steady 20 minutes between flashes, sometimes there was an 11-minute signal and at other times a 21-minute pulse.

    “We had never seen anything like this before,” Garnavich said. “For two hours, it would flash quickly and then the next two hours it would pulse more slowly.”

    The Sarah L. Krizmanich Telescope, installed on the roof of the Jordan Hall of Science in 2013, features a 0.8-meter (32-inch diameter) mirror. It provides undergraduate and graduate students cutting-edge technology for research and is used to test new instrumentation developed in the Department of Physics at Notre Dame.

    The Notre Dame team that studied FO Aquarii included Littlefield, Aadland and Kennedy. The team’s findings have been published in the Astrophysical Journal. Institutions that contributed to the work include The Ohio State University, University Cote d’Azur (France), University de Liege (Belgium) and the American Association of Variable Star Observers (AAVSO)

    See the full article here .

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    Notre Dame Campus

    The University of Notre Dame du Lac (or simply Notre Dame /ˌnoʊtərˈdeɪm/ NOH-tər-DAYM) is a Catholic research university located near South Bend, Indiana, in the United States. In French, Notre Dame du Lac means “Our Lady of the Lake” and refers to the university’s patron saint, the Virgin Mary.

    The school was founded by Father Edward Sorin, CSC, who was also its first president. Today, many Holy Cross priests continue to work for the university, including as its president. It was established as an all-male institution on November 26, 1842, on land donated by the Bishop of Vincennes. The university first enrolled women undergraduates in 1972. As of 2013 about 48 percent of the student body was female.[6] Notre Dame’s Catholic character is reflected in its explicit commitment to the Catholic faith, numerous ministries funded by the school, and the architecture around campus. The university is consistently ranked one of the top universities in the United States and as a major global university.

    The university today is organized into five colleges and one professional school, and its graduate program has 15 master’s and 26 doctoral degree programs.[7][8] Over 80% of the university’s 8,000 undergraduates live on campus in one of 29 single-sex residence halls, each of which fields teams for more than a dozen intramural sports, and the university counts approximately 120,000 alumni.[9]

    The university is globally recognized for its Notre Dame School of Architecture, a faculty that teaches (pre-modernist) traditional and classical architecture and urban planning (e.g. following the principles of New Urbanism and New Classical Architecture).[10] It also awards the renowned annual Driehaus Architecture Prize.

     
  • richardmitnick 1:05 pm on January 16, 2017 Permalink | Reply
    Tags: , , , , , , ,   

    From Motherboard: “An Earth-Sized Telescope is About to ‘See’ a Black Hole For the First Time” 

    motherboard

    Motherboard

    January 13, 2017
    William Rauscher

    We were perched dizzyingly high in the Chilean Andes, ringed by a herd of sixty-six white giants. Through the broad windows of the low, nondescript building in which we stood, we could see massive white radio antennas outside against the Martian-red soil of the desolate Chajnantor Plateau, their dishes thrust towards a pure blue sky.

    This is the Atacama Large Millimeter Array, also known as ALMA—one of the world’s largest radio telescope arrays, an international partnership that spans four continents. In spring of 2017, ALMA, along with eight other telescopes around the world, will aim towards the center of the Milky Way, around 25,000 light years from Earth, in an attempt to capture the first-ever image of a black hole. This is part of a daring astronomy project called the Event Horizon Telescope (EHT).

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

    My partner Dave Robertson and I took turns huffing from a can of oxygen to stave off the altitude sickness that can come on at 16,500 feet. Our guide Danilo Vidal, an energetic Chilean who wore his dark hair in a ponytail, pointed to a grey metal door with a glass window. “If we open that door,” said Vidal, “everyone in science will hate us for the rest of our lives.” Confused by this cryptic statement, I took another hit from the oxygen and peered through the glass, into the heart of the experiment.

    Among a small forest of processors, I could see an eggshell-white box that resembled a dorm room refrigerator. Inside was the brand-new maser, an ultraprecise atomic clock that syncs up every antenna on-site, and then syncs ALMA itself to the Event Horizon Telescope’s global network, lending so much dish-space and processing power that it effectively doubles the entire network’s resolution.

    1
    Christophe Jacques of the NRAO inspects the wiring on ALMA’s new hydrogen maser atomic clock during installation. Image: Carlos Padilla/NRAO/AUI/NSF

    To keep equipment from overheating, the room is kept at an absurdly low temperature—very close to absolute zero. If we opened the door, Vidal explained, emergency systems would instantly shut down the maser to protect it, and ALMA’s beating heart would stop, ruining multiple international astronomy projects, including the EHT.

    Claudio Follert, an ALMA fiber-optic specialist in his mid-fifties, was there in 2014 when the maser first arrived—he told me it was a machine he had never seen before, carried in by strange men. The men were sent by the EHT, which is based out of MIT.

    The EHT is made possible by the maser’s astonishing precision—about one billion times more precise than the clock in your smartphone.

    Designed by an international team led by MIT scientist Shep Doeleman, the EHT is the first of its kind-a global telescope network that uses a technique called interferometry to synthesize astronomical data from multiple sources, each with its own maser—including ALMA in Chile, the Large Millimeter Telescope atop the Sierra Negra volcano in Mexico, and the National Radio Astronomy Observatory in Virginia.

    Together, these telescopes create a super-telescope that is quite literally the size of the Earth, with enough resolution to photograph an orange on the Moon.

    With ALMA recently added to this Avengers-like team of radio telescopes, the network is ten times more sensitive. As a result, Doeleman’s group believes it has the firepower to penetrate the interstellar gases that cloak their targets: supermassive black holes. Drawn into orbit by the black holes’ gravity, these gases form gargantuan clouds that yield nothing to optical telescopes.

    Faint radio signals from the black holes, on the other hand, slip through the gas clouds and are ultimately detected on Earth.

    Black holes are the folk legends of outer space. Since no light can escape them, they’re invisible to the eye, and we have no confirmation that they actually exist—only heaps of indirect evidence, particularly the gravitational wobbles in orbits of nearby stars, the behavior of interstellar gas clouds, and the gaseous jets that spew into space when an unseen source of extreme gravity appears to rip cosmic matter to shreds.

    Black holes challenge our most fundamental beliefs about reality. Visionary scientific minds, including the theoretical physicists Stephen Hawking and Kip Thorne, have devoted entire books to unpacking the hallucinatory scenarios thought to be induced by black holes’ gravitational forces—imagine the bottom of your body violently wrenched away from the top, physically stretching you like a Looney Tunes character, a scenario that Thorne’s Black Holes and Time Warps paints in stomach-churning detail.

    2
    An image from the heart of the Milky Way from NASA’s Chandra X-ray Observatory. The supermassive black hole is at the center. Image: NASA/CXC/MIT/F. Baganoff et al.

    NASA/Chandra Telescope
    NASA/Chandra Telescope

    Sag A*  NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way
    Sag A* NASA Chandra X-Ray Observatory 23 July 2014, the supermassive black hole at the center of the Milky Way

    Black holes are thought to lurk at the centers of galaxies including our own. Prove the existence of Sagittarius A*, the supermassive black hole at the heart of the Milky Way, and you are one step closer to solving another mystery: the origin of humankind, and all life as we know it.

    “The black hole at the center of our galaxy has everything to do with our own origin,” said Violette Impellizzeri, an ALMA astronomer collaborating with Event Horizon Telescope. Supermassive black holes are thought to regulate the stars that surround them, influencing their formation and orbit. “Understanding how our galaxy was formed leads to our own origin directly,” she said.

    Scientists estimate the mass of Sagittarius A* to be four million times that of our Sun, yet its diameter is roughly equal to the distance from our sun to Mercury—not much, in cosmic terms. The resulting density produces gravity so strong that space and time distort around it, making it invisible.

    The current theory, espoused by Thorne, is that the distance from the center of a black hole, known as the singularity, to its edge, known as the event horizon, becomes so warped that it nears infinite length, and light simply runs out of energy as it tries to escape.

    It took Doeleman, the project leader at MIT, to decide that in order to see the unseeable, you would first have to create a new kind of vision. With ALMA as part of the giant EHT network, we can take a radio “photograph” of the matter that orbits Sagittarius A*—called the accretion disk—and finally see the black hole in shadow: its first-ever portrait.

    • Vidal and Follert, the guide and fiber-optic specialist, led us out onto the plateaus. There was work to do: one of the antennas was hobbled by a damaged radio receptor.

    It was blindingly bright and windy, not to mention dry—Chajnantor is located in Chile’s Atacama Desert, the driest place on Earth, if you don’t count the poles. Completely inhospitable for human beings, Chajnantor is an ideal setting for a radio telescope: the elevation puts it closer to the stars, and the strikingly low water vapor keeps the cosmic signals pristine.

    For some, like ALMA’s crew, as well as Doeleman, the extreme environment is part of the attraction. “I just love getting to the telescopes,” he said. At 50, Doeleman is fresh-faced, with glasses and thinning hair that make him look every part the bookish scientist. His outgoing personality and entrepreneurial vigor reflect an explorer’s spirit more at home in the field than behind a desk.

    Doeleman regularly travels to each EHT site around the world, many of them located in extreme environments like the Andes or the Sierra Negra. “The adventure part is what motivates me—driving along dirt roads, up the sides of mountains, to install new instruments, doing observations that have never been done before. It’s a little bit like Jacques Cousteau—we’re not sitting in armchairs in our offices.”

    Outside on Chajnantor, I felt light-headed. I tried to keep my breathing steady: low oxygen can quickly wreck your mental faculties. On the plateau, Dave and I were dwarfed by ALMA’s antennas, which blocked out the desert sun. They felt powerful and eerie, like Easter Island statues. Even when standing directly beneath these behemoths, it wasn’t clear how they were controlled—the white dishes seemed to twist and pivot without warning.

    3
    Using a technique called interferometry, ALMA’s antennas can be configured to act as one giant antenna, and ALMA itself can be synced up with telescopes worldwide. Image: Dave Robertson

    An ALMA antenna is useless when one of its radio receptors is out of tune. We followed Follert up several steel ladders, boots clanging on metal, until we were in a low-ceilinged maintenance room inside one of the antennas. We helped him remove the damaged receptor, a long metal cylinder resembling a futuristic bazooka.

    Vidal drove us back down the mountain to the Operations Support Facility (OSF), ALMA’s headquarters, so we could see the lab where receptors are maintained.

    Per strict international regulations, Vidal was required to breathe through an oxygen tube as he drove, lest the high altitude cause him to lose consciousness behind the wheel.

    As we descended, Vidal radioed at regular intervals to identify our location. All around us the mountain slopes were red, rocky and barren—no wonder that NASA regularly deploys expeditions to this desert to replicate conditions on Mars.

    Located at 9,000 ft, the OSF is where ALMA’s staff call home: a total of 600 scientists working in shifts are based here, including engineers and technicians, from over 20 countries. The working conditions can be extreme. Staff hole up in weeklong shifts separated from friends and family, and endure the short and long-term health risks of high elevation, including a stroke or pulmonary edema, where fluid fills your lungs and you suffocate.

    It is thus maybe not surprising to find out that the entire staff are monitored regularly by medical personnel, and that emergency oxygen and a hyperbaric chamber are on-hand.

    They unwind by exercising and watching movies, although certain sci-fi flicks are frowned upon. “We need a break from space sometimes,” said Follert. Alcohol consumption on site is strictly forbidden—have even a tipple and you risk amplifying the physical effects of high elevation.

    4
    Aerial picture of ALMA’s Operations Support Facility. Image: Carlos Padilla/NRAO/AUI/NSF

    The close teamwork at ALMA is absolutely essential for the life of the observatory. Detecting cosmic radio signals, including those sent from a black hole, requires constant cooperation across teams, who must obsessively calibrate, maintain and repair their instruments to fend off unwanted noise.

    ALMA and the other telescopes on the EHT will soon turn towards the center of the Milky Way to tune in to the black hole’s narrow radio frequency. The data that ALMA collects will be so large, it cannot be transferred online. Instead, physical hard drives will shipped by “sneakernet”: loaded into the belly of a 747 and flown directly to MIT.

    When ALMA’s data is correlated with the other telescopes later this year, Sagittarius A* should appear against the glowing gas of the accretion disk. Maybe.

    Actually, said Doeleman, “we don’t know what we’re going to see. Nature can be cruel. We may see something boring. But we’re not married to one outcome—we’re going to see nature the way nature is.”

    See the full article here .

    The full EHT:

    Event Horizon Telescope Array

    Event Horizon Telescope map

    The locations of the radio dishes that will be part of the Event Horizon Telescope array. Image credit: Event Horizon Telescope sites, via University of Arizona at https://www.as.arizona.edu/event-horizon-telescope.

    Arizona Radio Observatory
    Arizona Radio Observatory/Submillimeter-wave Astronomy (ARO/SMT)

    ESO/APEX
    Atacama Pathfinder EXperiment (APEX)

    CARMA Array no longer in service
    Combined Array for Research in Millimeter-wave Astronomy (CARMA)

    Atacama Submillimeter Telescope Experiment (ASTE)
    Atacama Submillimeter Telescope Experiment (ASTE)

    Caltech Submillimeter Observatory
    Caltech Submillimeter Observatory (CSO)

    IRAM NOEMA interferometer
    Institut de Radioastronomie Millimetrique (IRAM) 30m

    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA
    James Clerk Maxwell Telescope interior, Mauna Kea, Hawaii, USA

    Large Millimeter Telescope Alfonso Serrano
    Large Millimeter Telescope Alfonso Serrano

    CfA Submillimeter Array Hawaii SAO
    Submillimeter Array Hawaii SAO

    Future Array/Telescopes

    ESO/NRAO/NAOJ ALMA Array
    ESO/NRAO/NAOJ ALMA Array, Chile

    Plateau de Bure interferometer
    Plateau de Bure interferometer

    South Pole Telescope SPTPOL
    South Pole Telescope SPTPOL

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    The future is wonderful, the future is terrifying. We should know, we live there. Whether on the ground or on the web, Motherboard travels the world to uncover the tech and science stories that define what’s coming next for this quickly-evolving planet of ours.

    Motherboard is a multi-platform, multimedia publication, relying on longform reporting, in-depth blogging, and video and film production to ensure every story is presented in its most gripping and relatable format. Beyond that, we are dedicated to bringing our audience honest portraits of the futures we face, so you can be better informed in your decision-making today.

     
    • Jim Ruebush 1:51 pm on January 16, 2017 Permalink | Reply

      Very interesting. I look forward to seeing results. The radio telescopes at Atacama are the subject of a blog post of mine a few years ago. http://bit.ly/2jpp7hl

      Only 2 miles from my home in Iowa is a radio telescope part of the VLBA. I’ve been fortunate to go up inside and stand in the dish. What fun.

      Keep up the good work and posts.

      Like

  • richardmitnick 12:06 pm on January 16, 2017 Permalink | Reply
    Tags: ASKAP finally hits the big-data highway, , , , , , , , WALLABY - Widefield ASKAP L-band Legacy All-sky Blind surveY   

    From The Conversation for SKA: “The Australian Square Kilometre Array Pathfinder finally hits the big-data highway” 

    Conversation
    The Conversation

    SKA Square Kilometer Array

    SKA

    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia
    SKA/ASKAP radio telescope at the Murchison Radio-astronomy Observatory (MRO) in Mid West region of Western Australia

    January 15, 2017
    Douglas Bock
    Director of Astronomy and Space Science, CSIRO

    Antony Schinckel
    ASKAP Director, CSIRO

    You know how long it takes to pack the car to go on holidays. But there’s a moment when you’re all in, everyone has their seatbelt on, you pull out of the drive and you’re off.

    Our ASKAP (Australian Square Kilometre Array Pathfinder) telescope has just pulled out of the drive, so to speak, at its base in Western Australia at the Murchison Radio-astronomy Observatory (MRO), about 315km northeast of Geraldton.

    ASKAP is made of 36 identical 12-metre wide dish antennas that all work together, 12 of which are currently in operation. Thirty ASKAP antennas have now been fitted with specialised phased array feeds, the rest will be installed later in 2017.

    Until now, we’d been taking data mainly to test how ASKAP performs. Having shown the telescope’s technical excellence it’s now off on its big trip, starting to make observations for the big science projects it’ll be doing for the next five years.

    And it’s taking lots of data. Its antennas are now churning out 5.2 terabytes of data per second (about 15 per cent of the internet’s current data rate).

    Once out of the telescope, the data is going through a new, almost automatic data-processing system we’ve developed.

    It’s like a bread-making machine: put in the data, make some choices, press the button and leave it overnight. In the morning you have a nice batch of freshly made images from the telescope.

    Go the WALLABIES

    The first project we’ve been taking data for is one of ASKAP’s largest surveys, WALLABY (Widefield ASKAP L-band Legacy All-sky Blind surveY).

    On board the survey are a happy band of 100-plus scientists – affectionately known as the WALLABIES – from many countries, led by one of our astronomers, Bärbel Koribalski, and Lister Staveley-Smith of the International Centre for Radio Astronomy Research (ICRAR), University of Western Australia.

    They’re aiming to detect and measure neutral hydrogen gas in galaxies over three-quarters of the sky. To see the farthest of these galaxies they’ll be looking three billion years back into the universe’s past, with a redshift of 0.26.

    2
    Neutral hydrogen gas in one of the galaxies, IC 5201 in the southern constellation of Grus (The Crane), imaged in early observations for the WALLABY project. Matthew Whiting, Karen Lee-Waddell and Bärbel Koribalski (all CSIRO); WALLABY team, Author provided

    Neutral hydrogen – just lonely individual hydrogen atoms floating around – is the basic form of matter in the universe. Galaxies are made up of stars but also dark matter, dust and gas – mostly hydrogen. Some of the hydrogen turns into stars.

    Although the universe has been busy making stars for most of its 13.7-billion-year life, there’s still a fair bit of neutral hydrogen around. In the nearby (low-redshift) universe, most of it hangs out in galaxies. So mapping the neutral hydrogen is a useful way to map the galaxies, which isn’t always easy to do with just starlight.

    But as well as mapping where the galaxies are, we want to know how they live their lives, get on with their neighbours, grow and change over time.

    When galaxies live together in big groups and clusters they steal gas from each other, a processes called accretion and stripping. Seeing how the hydrogen gas is disturbed or missing tells us what the galaxies have been up to.

    We can also use the hydrogen signal to work out a lot of a galaxy’s individual characteristics, such as its distance, how much gas it contains, its total mass, and how much dark matter it contains.

    This information is often used in combination with characteristics we learn from studying the light of the galaxy’s stars.

    Oh what big eyes you have ASKAP

    ASKAP sees large pieces of sky with a field of view of 30 square degrees. The WALLABY team will observe 1,200 of these fields. Each field contains about 500 galaxies detectable in neutral hydrogen, giving a total of 600,000 galaxies.

    3
    One of the first fields targeted by WALLABY, the NGC 7232 galaxy group. Ian Heywood (CSIRO); WALLABY team, Author provided

    This image (above) of the NGC 7232 galaxy group was made with just two nights’ worth of data.

    ASKAP has now made 150 hours of observations of this field, which has been found to contain 2,300 radio sources (the white dots), almost all of them galaxies.

    It has also observed a second field, one containing the Fornax cluster of galaxies, and started on two more fields over the Christmas and New Year period.

    Even more will be dug up by targeted searches. Simply detecting all the WALLABY galaxies will take more than two years, and interpreting the data even longer. ASKAP’s data will live in a huge archive that astronomers will sift through over many years with the help of supercomputers at the Pawsey Centre in Perth, Western Australia.

    ASKAP has nine other big survey projects planned, so this is just the beginning of the journey. It’s really a very exciting time for ASKAP and the more than 350 international scientists who’ll be working with it.

    Who knows where this Big Trip will take them, and what they’ll find along the way?

    See the full article here .

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    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 11:32 am on January 16, 2017 Permalink | Reply
    Tags: A slice of Sagittarius, , , NASA/ESA Hubble ACS   

    From Hubble: “A slice of Sagittarius” 

    NASA Hubble Banner

    NASA/ESA Hubble Telescope

    NASA/ESA Hubble Telescope

    1
    Credit: NASA/ESA Hubble

    16 January 2017
    No writer credit found

    This stunning image, captured by the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys (ACS), shows part of the sky in the constellation of Sagittarius (The Archer).

    NASA/ESA Hubble ACS

    The region is rendered in exquisite detail — deep red and bright blue stars are scattered across the frame, set against a background of thousands of more distant stars and galaxies. Two features are particularly striking: the colours of the stars, and the dramatic crosses that burst from the centres of the brightest bodies.

    While some of the colours in this frame have been enhanced and tweaked during the process of creating the image from the observational data, different stars do indeed glow in different colours. Stars differ in colour according to their surface temperature: very hot stars are blue or white, while cooler stars are redder. They may be cooler because they are smaller, or because they are very old and have entered the red giant phase, when an old star expands and cools dramatically as its core collapses.
    The crosses are nothing to do with the stars themselves, and, because Hubble orbits above Earth’s atmosphere, nor are they due to any kind of atmospheric disturbance. They are actually known as diffraction spikes, and are caused by the structure of the telescope itself. Like all big modern telescopes, Hubble uses mirrors to capture light and form images. Its secondary mirror is supported by struts, called telescope spiders, arranged in a cross formation, and they diffract the incoming light. Diffraction is the slight bending of light as it passes near the edge of an object. Every cross in this image is due to a single set of struts within Hubble itself! Whilst the spikes are technically an inaccuracy, many astrophotographers choose to emphasise and celebrate them as a beautiful feature of their images.

    See the full article here .

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

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    NASA image

     
  • richardmitnick 11:03 am on January 16, 2017 Permalink | Reply
    Tags: Chicxulub crater Mexico asteroid, Computer simulations tell a story, How the darkness and the cold killed the dinosaurs, , The sudden extinction of the dinosaurs started the ascent of the mammals   

    From phys.org: “How the darkness and the cold killed the dinosaurs” 

    physdotorg
    phys.org

    January 16, 2017
    No writer credit found

    1
    Tyrannosaurus Rex “Tristan”, on display at the Museum für Naturkunde – Leibniz Institute for Evolution and Biodiversity Science in Berlin with which PIK is cooperating. Credit: Carola Radke/Museum für Naturkunde

    66 million years ago, the sudden extinction of the dinosaurs started the ascent of the mammals, ultimately resulting in humankind’s reign on Earth. Climate scientists have now reconstructed how tiny droplets of sulfuric acid formed high up in the air after the well-known impact of a large asteroid, which blocked the sunlight for several years, and had a profound influence on life. Plants died, and death cascaded through the food web. Previous theories focused on the shorter-lived dust ejected by the impact. New computer simulations show that the droplets resulted in long-lasting cooling, a likely contributor to the death of land-living dinosaurs. An additional kill mechanism might have been a vigorous mixing of the oceans caused by the surface cooling, severely disturbing marine ecosystems.

    “The big chill following the impact of the asteroid that formed the Chicxulub crater in Mexico is a turning point in Earth history,” says Julia Brugger from the Potsdam Institute for Climate Impact Research (PIK), lead author of the study to be published today in Geophysical Research Letters. “We can now contribute new insights for understanding the much-debated ultimate cause for the demise of the dinosaurs at the end of the Cretaceous era.”

    To investigate the phenomenon, the scientists for the first time used a specific kind of computer simulation normally applied in other contexts, a climate model combining atmosphere, ocean and sea ice. They build on research showing that sulfur-bearing gases that evaporated from the violent asteroid impact on the planet’s surface were the main factor for blocking the sunlight and cooling down Earth.

    “It became cold. I mean, really cold,” says Brugger. Global annual mean surface air temperature dropped by at least 26 degrees Celsius. The dinosaurs were used to living in a lush climate. After the asteroid’s impact, the annual average temperature was below freezing for about three years. Evidently, the ice caps expanded. Even in the tropics, annual mean temperatures went from 27 degrees to a mere five degrees. “The long-term cooling caused by the sulfate aerosols was much more important for the mass extinction than the dust that stayed in the atmosphere for only a relatively short time. It was also more important than local events like the extreme heat close to the impact, wildfires or tsunamis,” says co-author Georg Feulner who leads the research team at PIK. It took the climate about 30 years to recover, the scientists found.

    Additionally, ocean circulation became disturbed. Surface waters cooled down, thereby becoming denser and thus heavier. While these cooler water masses sank into the depths, warmer water from deeper ocean layers rose to the surface, carrying nutrients that likely led to massive blooms of algae, the scientists argue. It is conceivable that these algal blooms produced toxic substances, further affecting life at the coasts. Yet in any case, marine ecosystems were severely altered, and this likely contributed to the extinction of species in the oceans, including the ammonites.

    The dinosaurs, until then the masters of the Earth, made space for the rise of the mammals, and eventually humankind. The study of Earth’s past also shows that efforts to study future threats by asteroids are of more than just academic interest. “It is fascinating to see how evolution is partly driven by accidents like an asteroid’s impact—mass extinctions show that life on Earth is vulnerable,” says Feulner. “It also illustrates how important the climate is for all lifeforms on our planet. Ironically, today, the most immediate threat is not from natural cooling but from human-made global warming.”

    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 10:39 am on January 16, 2017 Permalink | Reply
    Tags: , , , , There are at least two trillion galaxies in the universe ten times more than previously thought,   

    From U Nottingham: “There are at least two trillion galaxies in the universe, ten times more than previously thought” 

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    University of Nottingham

    13 Oct 2016 [Just turned up in a social media search]
    Lindsay Brooke
    Media Relations Manager
    lindsay.brooke@nottingham.ac.uk
    +44 (0)115 951 5751
    Location: University Park

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    Image of the HST GOODS-South field, one of the deepest images of the sky but covering just one millionth of its total area. The new estimate for the number of galaxies is ten times higher than the number seen in this image. Credit: NASA / ESA / The GOODS Team / M. Giavalisco (UMass., Amherst)

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    Astronomers have long sought to determine how many galaxies there are in the universe. This is a fundamental question that we have only been able to address with any certainty due to new scientific results.

    During the past 20 years very deep Hubble Space Telescope images have found a myriad of faint galaxies, and it was approximated that the observable Universe contains about 100 billion galaxies in total.

    Now, an international team, led by Christopher Conselice, Professor of Astrophysics at The University of Nottingham, has shown that the actual number is much higher than this.

    Professor Conselice and his team has shown that the number of galaxies in our universe is at least two trillion – ten times more than previously thought – the often quoted value of around 100 Billion.

    Current astronomical technology allows us to study a fraction of these galaxies– just 10%.

    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey
    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey

    It means that over 90% of the galaxies in our universe have yet to be discovered, and will only be seen once bigger and better telescopes are developed.

    ESO 50 Large
    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile
    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile

    LSST
    LSST/Camera, built at SLAC
    LSST/Camera, built at SLAC
    LSST Interior
    LSST telescope, currently under construction at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.
    LSST telescope, currently under construction at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes

    TMT-Thirty Meter Telescope, proposed for Mauna Kea, Hawaii, USA
    TMT-Thirty Meter Telescope, proposed for Mauna Kea, Hawaii, USA

    Giant Magellan Telescope, Las Campanas Observatory, to be built  some 115 km (71 mi) north-northeast of La Serena, Chile
    Giant Magellan Telescope, Las Campanas Observatory, to be built some 115 km (71 mi) north-northeast of La Serena, Chile

    NASA/ESA/CSA Webb Telescope annotated
    NASA/ESA/CSA Webb Telescope annotated

    NASA/WFIRST telescope
    NASA/WFIRST telescope

    The research – The Evolution of Galaxy number density at Z < 8 and its implications – is published today (October 13, 2016) in the Astrophysical Journal – the foremost research journal in the world dedicated to recent developments, discoveries and theories about astronomy and astrophysics.

    The results have clear implications for galaxy formation, and also help solve an ancient astronomical paradox — why is the sky dark at night?

    Professor Conselice said: “We are missing the vast majority of galaxies because they are very faint and far away. The number of galaxies in the universe is a fundamental number we would like to know, and it boggles the mind that over 90% of the galaxies in the universe have yet to be studied.

    Who knows what interesting properties we will find when we study these galaxies with the next generation of telescopes. These galaxies will likely hold the clues to many outstanding astrophysical issues.”

    Intergalactic archaeological dig

    Professor Conselice’s research is the culmination of 15 year’s work. His team converted pencil beam images of deep space from telescopes around the world, and especially from the Hubble telescope into 3D maps to calculate the volume as well as the density of galaxies of one tiny bit of space after another.

    This painstaking research enabled him to establish how many galaxies we have missed – much like an intergalactic archaeological dig.

    The results of this study are based on the measurements of the number of galaxies at different epochs – different instances in time – through the universe’s history.

    When Professor Conselice and his team at Nottingham, in collaboration with scientists from the Leiden Observatory at Leiden University in the Netherlands and the Institute for Astronomy at the University of Edinburgh, examined how many galaxies there were in a given value they found that this increased significantly at earlier times.

    In fact, it appears that there are a factor of 10 more galaxies in a given volume of space when the universe was a few billion years old compared with today. Most of these galaxies are low mass systems with masses similar to those of the satellite galaxies surrounding the Milky Way.

    Professor Conselice said: “This is very surprising as we know that over the 13.7 billion years of cosmic evolution galaxies are growing through star formation and merging with other galaxies. Thus, to find that there were in fact more galaxies in the past implies that that significant evolution in galaxies must have occurred to reduce the number of galaxies through extensive merging of systems. This also gives us a verification of the top-down formation of structure in the universe.”

    Probing cosmic history answers astronomical questions

    By probing deep into space Professor Conselice and his team have been able to go way back in time – more than 13 billion years in the past – to find out how our universe evolved and answer some vexing questions.

    The implications of this research are many, for instance; galaxies are likely to be forming by merging together. This decreases the number of systems as time progresses which provides a possible solution to Oblers’ paradox – why the sky is dark at night?

    Solutions to this in the past were based on the fact that the universe is finite in size as well as in time. However, if we consider all the undiscovered galaxies then in principle the critiera for Oblers’ paradox is met.

    However, most galaxies in the universe are very distant and their light is absorbed by gas in intergalactic space. Otherwise, we would see the night sky lit up everywhere.

    See the full article here .

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    2

    “The University of Nottingham shares many of the characteristics of the world’s great universities. However, we are distinct not only in our key strengths but in how our many strengths combine: we are financially secure, campus based and comprehensive; we are research-led and recruit top students and staff from around the world; we are committed to internationalising all our core activities so our students can have a valuable and enjoyable experience that prepares them well for the rest of their intellectual, professional and personal lives.”

     
  • richardmitnick 9:41 am on January 16, 2017 Permalink | Reply
    Tags: , , Autism Risk May Arise From Sex-Specific Traits, , , SNP - single nucleotide polymorphism   

    From SA: “Autism Risk May Arise From Sex-Specific Traits” 

    Scientific American

    Scientific American

    January 16, 2017
    Ann Griswold

    Genetic sequences that code for physical features that differ between boys and girls also seem to contribute to risk for the disorder.

    1
    Alena Baranova, EyeEm, Getty Images

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    Basic biology: Different genetic variants contribute to autism risk in boys versus girls. Alfred Pasieka / Science Photo Library

    Genetic variants that shape physical features that vary with sex, such as waist-to-hip ratio, may also affect autism risk, according to a new study.

    Many of the genes involved in these features are not linked to autism or even the brain. Instead, they help establish basic physical differences between the sexes, says lead investigator Lauren Weiss, associate professor of psychiatry at the University of California, San Francisco.

    “Whatever general biological sex differences cause a [variant] to have a different effect on things like height in males and females, those same mechanisms seem to be contributing to autism risk,” she says. The work appeared in November in PLOS Genetics.

    The results bolster the notion that mutations in some genes contribute to autism’s skewed sex ratio: The condition is diagnosed in about five boys for every girl. That may be because girls require a bigger genetic hit to show features of the condition, because sex hormones in the womb boost the risk in boys or because autism is easier to detect in boys than in girls.

    The new study is the first to look at sex differences in common genetic variants called single nucleotide polymorphisms (SNPs). It shows that the sexes differ in which autism-linked SNPs they have, but not in the overall number of such SNPs.

    Separate sets:

    Weiss and her team analyzed published genetic data from four databases and unpublished data from five others. Altogether, they reviewed information from 8,646 individuals with autism, including 1,468 girls and women. They also analyzed data from 15,028 controls, some of whom are related to people in the autism group.

    The researchers first identified SNPs that differ between males with autism and their unaffected family members and unrelated controls. They then repeated the procedure for girls and women with autism.

    These two analyses revealed distinct sets of SNPs associated with autism: a set of five SNPs in boys and men and a separate set of three SNPs in girls and women. None of the variants have previously been associated with autism.

    The researchers then compared males who have autism with females who have the condition. They found similar levels of genetic variation in the two groups, with equal numbers of autism risk genes affected. This result suggests that common variants do not contribute to a stronger genetic hit in girls with autism.

    Body of data:

    When the researchers compared people who have autism with controls, they did not find any differences in SNPs in genes that respond to sex hormones.

    The team then looked at 11 SNPs known to influence height, weight, body mass index, hip and waist measurements in women, and 15 variants that influence these physical traits in men. They found more of these sex-specific SNPs in people with autism than in controls. None of these SNPs have previously been associated with autism.

    The findings suggest that different SNPs contribute to autism risk in boys and girls.

    The fact that some of these SNPs also shape physical traits in a sex-specific way is particularly interesting, says Meng-Chuan Lai, assistant professor in psychiatry at the University of Toronto, who was not involved in the study. Scientists should examine whether sex differences in brain structure in people with autism track with the sex-specific SNPs, he says.

    Weiss says she hopes the findings will spur researchers to pay more attention to the influences of sex when sifting through genomic data. Outfitting genetic repositories with the option to sort data by sex would be the next step for that approach.

    See the full article here .

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  • richardmitnick 9:00 am on January 16, 2017 Permalink | Reply
    Tags: , , ,   

    From COSMOS: “Before the dinosaurs” Wow!! 

    Cosmos Magazine bloc

    COSMOS

    1.15.17
    James Mitchell Crow

    Before the dinosaurs Credit: Julius Csotonyi

    Welcome to the dawn of the Permian, 290 million years ago. Reptiles with waterproof skin and eggs are colonising the land.

    They are not dinosaurs, but synapsids: a group defined by the single hole in the skull behind each eye where jaw muscles attach. Mammals are synapsids too, so these creatures are more closely related to us than to dinosaurs.

    Sail-backed synapsids, like the plant-eating Edaphosaurus on the right, are common. They can grow up to 3.5 metres long. The carnivorous Dimetrodon, at back left, is a little longer, reaching up to 4.6 metres. The sails on these species may have heated and cooled the body. Skulking in the left foreground is the massive-skulled Ophiacodon. These early synapsids are known as pelicosaurs.

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    The first therapsids

    By the mid-Permian, pelicosaurs are being displaced by therapsids. This group was becoming more mammal-like: their legs were positioned vertically under their body and they had three types of teeth – incisors, canines and molars. (A reptile’s teeth may be different sizes but they are all the same shape). Some were also thought to have fur and be warm- blooded.

    Dinocephalians, a sub-group distinguished by their interlocking incisors, dominated the mid-Permian. They weighed up to two tonnes. Dinocephalians included herbivores such as this herd of Estemmenosuchus or Ulemosaurus, represented by the fossil, and the carnivorous Eotitanosuchus, emerging from the water, which could reach a length of five metres. The whole group mysteriously disappeared around 270 million years ago.

    Credits: (artist impression) Julius Csotonyi / (fossil) Gondwana Studios

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    4

    Gorgonopsids

    Gorgonopsids, a later group of therapsids, were fearsome carnivores. The name refers to the Greek monster the Gorgon. Some of the largest examples include the three-metre-long Inostrancevia (see fossil), and the similarly sized Dinogorgons, shown here fighting over a carcass.

    Gorgonopsids were characterised by their large, powerful jaws and sabre-teeth. But their mighty incisors could not save them from the biggest mass extinction event in Earth’s history. Thought to have been triggered by a series of massive volcanic eruptions in what is now Siberia, 80-90% of plant and animal species disappeared in what is known as The Great Dying. It marked the end of the Permian and the start of the Triassic.

    Credits: (artist impression) Julius Csotonyi / (fossil) Gondwana Studios

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    6

    Cynodont survivors

    The therapsids were almost wiped out in the Great Dying, clearing the way for dinosaurs. They were diapsids – distinguishable by two holes in the skull behind each eye socket, like modern-day birds and lizards.

    A handful of therapsids survived. Among them were the herds of herbivorous Lystrosaurus, shown at the water’s edge and in fossilised form. And most importantly for us, the cynodonts: the ancestors of mammals. One is shown here edging out onto the finger of rock.

    Little holes in the fossilised snouts of cynodonts suggest they had whiskers, which means they probably had fur and were warm-blooded.

    The cynodonts lived in the dinosaurs’ shadow for 200 million years, until a mass extinction triggered by a crashing comet favoured this ancient lineage once again.

    Credits: (artist impression) Julius Csotonyi / (fossil) Ghedoghedo / Staatliches Museum für Naturkunde Stuttgart

    See the full article here .

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  • richardmitnick 9:41 pm on January 15, 2017 Permalink | Reply
    Tags: , , , , ELSI - Earth-Life Science Institute, EON - ELSI Origins Network, LUCA - the Last Universal Common Ancestor of Life on Earth, , Messy chemistry, Ribosomes,   

    From Many Worlds: “Messy Chemistry, Evolving Rocks, and the Origin of Life” 

    NASA NExSS bloc

    NASA NExSS

    Many Worlds

    Many Words icon

    2017-01-15
    Marc Kaufman

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    Ribosomes are life’s oldest and most universal assembly of molecules. Today’s ribosome converts genetic information (RNA) into proteins that carry out various functions in an organism. A growing number of scientists are exploring how earliest components of life such as the ribosome came to be. They’re making surprising progress, but the going remains tough. No image credit.

    Noted synthetic life researcher Steven Benner of Foundation for Applied Molecular Evolution is fond of pointing out that gooey tars are the end product of too many experiments in his field. His widely-held view is that the tars, made out of chemicals known to be important in the origin of life, are nonetheless a dead end to be avoided when trying to work out how life began.

    But in the changing world of origins of life research, others are asking whether those messy tars might not be a breeding ground for the origin of life, rather than an obstacle to it.

    One of those is chemist and astrobiologist Irena Mamajanov of the Earth-Life Science Institute (ELSI) in Tokyo. As she recently explained during an institute symposium, scientists know that tar-like substances were present on early Earth, and that she and her colleagues are now aggressively studying their potential role in the prebiotic chemical transformations that ultimately allowed life to emerge out of non-life.

    “We call what we do messy chemistry, and we think it can help shed light on some important processes that make life possible.”

    2
    Irena Mamajanov of the Earth-Life Science Institute (ELSI) in Tokyo was the science lead for a just completed symposium on emerging approaches to the origin of life question.

    It stands to reason that the gunky tar played a role, she said, because tars allow some essential processes to occur: They can concentrate compounds, it can encapsulate them, and they could provide a kind of primitive (messy) scaffolding that could eventually evolve into the essential backbones of a living entity.

    “Scientists in the field have tended to think of the origin of life as a process going from simple to more complex, but we think it may have gone from very complex — messy — to more structured.”

    Mamajanov is part of an unusual group gathered at (ELSI), a relatively new site on the campus of the Tokyo Institute of Technology for origin of life study with a mandate to be interdisciplinary and to think big and outside the box.

    ELSI just completed its fifth annual symposium, and it brought together researchers from a wide range of fields to share their research on what might have led to the emergence of life. And being so interdisciplinary, the ELSI gathering was anything but straight and narrow itself.

    There was talk of the “evolution” of prebiotic compounds; of how the same universal 30 to 50 genes can be found in all living things from bacteria to us; of the possibility that the genomes of currently alive microbes surviving in extreme environments provide a window into the very earliest life; and even that evolutionary biology suggests that life on other Earth-like planets may well have evolved to form rather familiar creatures.

    Except for that last subject, the focus was very much on ways to identify the last universal common ancestor (LUCA), and what about Earth made life possible and what about life changed Earth.

    Scientific interest in the origin of life on Earth (and potentially elsewhere) tends to wax and wane, in large part because the problem is so endlessly complex. It’s one of the biggest questions in science, but some say that it will never be fully answered.

    But there has been a relatively recent upsurge in attention being paid and in funding for origin of life researchers.

    The Japanese government gave $100 million to start and operate ELSI, the Simons Foundation has donated another $100 million for an origins of life institute at Harvard, the Templeton Foundation has made numerous origin of life grants and, as it has for years, the NASA Astrobiology Institute has funded researchers. Some of the findings and theories are most intriguing and represent a break of sorts from the past.

    For some decades now, the origins of life field has been pretty sharply divided. One group holds that life began when metabolism (a small set of reactions able to harness and transform energy ) arose spontaneously; others maintain that it was the ability of a chemical system to replicate itself (the RNA world) that was the turning point. Metabolism First versus the RNA First, plus some lower-profile theories.

    In keeping with its goal of bringing scientists and disciplines together and to avoid as much origin-of-life dogma as possible, Mamajanov sees their “messy chemistry” approach as a third way and a more non-confrontational approach. It’s not a model for how life began per se, but one of many new approaches designed to shed light and collect data about those myriad processes.

    “This division in the field is hurting science because people are not talking to each other ,” she said. “By design we’re not in one camp or another.”

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    Loren Williams of Georgia tech

    Another speaker who exemplified that approach was Loren Williams of Georgia Tech, a biochemist whose lab studies the genetic makeup of those universal 30 to 50 ribosomes (a complex molecule made of RNA molecules and proteins that form a factory for protein synthesis in cells.) He was principal investigator for the NASA Astrobiology Institute’s Georgia Tech Center for Ribosome Adaptation and Evolution from 2009-2014.

    His goal is to collect hard data on these most common genes, with the inference that they are the oldest and closest to LUCA.

    “What becomes quickly clear is that the models of the origin of life don’t fit the data,” he said. “What the RNA model predicts, for instance, is totally disconnected from this data. So what happens with this disconnect? The modelers throw away the data. They say it doesn’t relate. Instead, I ignore the models.”

    A primary conclusion of his work is that early molecules — rather like many symbiotic relationships in nature today — need each other to survive. He gave the current day example of the fig wasp, which spends its larval stage in a fig, then serves as a pollinator for the tree, and then survives on the fruit that appears.

    He sees a parallel “mutualism” in the ribosomes he studies. “RNA is made by protein; all protein is made by RNA,” he said. It’s such a powerful concept for him that he wonders if “mutualism” doesn’t define a living system from the non-living.

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    These stromatolites, wavelike patterns created by bacteria embedded in sediment, are 3.7 billion years old and may represent the oldest life on the planet. Photo by Allen Nutman

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    Stromalites, sedimentary structures produced by microorganisms, today at Shark Bay, Australia. Remarkably, the lifeform has survived through billions of years of radical transformation on Earth, catastrophes and ever-changing ecologies.

    A consistent theme of the conference was that life emerged from the geochemistry present in early Earth. It’s an unavoidable truth that leads down some intriguing pathways.

    As planetary scientist Marc Hirschmann of the University of Minnesota reported at the gathering, the Earth actually has far less carbon, oxygen, nitrogen and other elements essential for life than the sun, than most asteroids, than even intersellar space.

    Since Earth was initially formed with the same galactic chemistry as those other bodies and arenas, Hirschmann said, the story of how the Earth was formed is one of losing substantial amounts of those elements rather than, as is commonly thought, by gaining them.

    The logic of this dynamic raises the question of how much of those elements does a planet have to lose, or can lose, to be considered habitable. And that in turn requires examination of how the Earth lost so much of its primordial inheritance — most likely from the impact that formed the moon, the resulting destruction of the early Earth atmosphere, and the later movement of the elements into the depths of the planet via plate tectonics. It’s all now considered part of the origins story.

    And as argued by Charley Lineweaver, a cosmologist with the Planetary Science Institute and the Australian National University, it has become increasingly difficult to contend that life on other planets is anything but abundant, especially now that we know that virtually all stars have planets orbiting them and that many billions of those planets will be the size of Earth.

    Other planets will have similar geochemical regimes and some will have undergone events that make their distribution of elements favorable for life. And as described by Eric Smith, an expert in complex systems at ELSI and the Santa Fe Institute, the logic of physics says that if life can emerge then it will.

    Any particular planetary life may not evolve beyond single cell lifeforms for a variety of reasons, but it will have emerged. The concept of the “origin of life” has taken on some very new meanings.

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    ELSI was created in 2012 after its founders won a World Premier International Research Center Initiative grant from the Japanese government. The WPI grant is awarded to institutes with a research vision to become globally competitive centers that can attract the best scientists from around the world to come work in Japan.

    The nature and aims of ELSI and its companion group the ELSI Origins Network (EON) strike me as part of the story. They break many molds.

    The creators of ELSI, both Japanese and from elsewhere, say that the institute is highly unusual for its welcome of non-Japanese faculty and students. They stay for years or months or even weeks as visitors.

    While ELSI is an government-funded institute with buildings, professors, researchers and a mission (to greatly enhance origin of life study in Japan), EON is a far-flung collection of top international origins scientists of many disciplines. Their home bases are places like Princeton’s Institute for Advanced Study, Harvard, Columbia, Dartmouth, Caltech and the University of Minnesota, among others in the U.S., Europe and Asia. NASA officials also play a supporting, but not financial, role.

    ELSI postdocs and other students live in Tokyo, while the EON fellows spend six months at ELSI and six months at home institutions. All of this is in the pursuit of scientific collaboration, exposing young scientists in one field related to origins to those in another, and generally adding to global knowledge about the sprawling subject of origins of life.

    Jim Cleaves, of ELSI and the Institute for Advanced Study, is the director of EON and an ambassador of sorts for its unusual mission. He, and others at the ELSI symposium, are eager to share their science and want young scientists interested in the origins of life to know there are many opportunities with ELSI and EON for research, study and visitorships on the Tokyo campus.

    See the full article here .

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    About Many Worlds

    There are many worlds out there waiting to fire your imagination.

    Marc Kaufman is an experienced journalist, having spent three decades at The Washington Post and The Philadelphia Inquirer, and is the author of two books on searching for life and planetary habitability. While the “Many Worlds” column is supported by the Lunar Planetary Institute/USRA and informed by NASA’s NExSS initiative, any opinions expressed are the author’s alone.

    This site is for everyone interested in the burgeoning field of exoplanet detection and research, from the general public to scientists in the field. It will present columns, news stories and in-depth features, as well as the work of guest writers.

    About NExSS

    The Nexus for Exoplanet System Science (NExSS) is a NASA research coordination network dedicated to the study of planetary habitability. The goals of NExSS are to investigate the diversity of exoplanets and to learn how their history, geology, and climate interact to create the conditions for life. NExSS investigators also strive to put planets into an architectural context — as solar systems built over the eons through dynamical processes and sculpted by stars. Based on our understanding of our own solar system and habitable planet Earth, researchers in the network aim to identify where habitable niches are most likely to occur, which planets are most likely to be habitable. Leveraging current NASA investments in research and missions, NExSS will accelerate the discovery and characterization of other potentially life-bearing worlds in the galaxy, using a systems science approach.
    The National Aeronautics and Space Administration (NASA) is the agency of the United States government that is responsible for the nation’s civilian space program and for aeronautics and aerospace research.

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

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

    NASA science is focused on better understanding Earth through the Earth Observing System, advancing heliophysics through the efforts of the Science Mission Directorate’s Heliophysics Research Program, exploring bodies throughout the Solar System with advanced robotic missions such as New Horizons, and researching astrophysics topics, such as the Big Bang, through the Great Observatories [Hubble, Chandra, Spitzer, and associated programs. NASA shares data with various national and international organizations such as from the [JAXA]Greenhouse Gases Observing Satellite.

     
  • richardmitnick 1:23 pm on January 15, 2017 Permalink | Reply
    Tags: A “planetary embryo” called Theia, , , ,   

    From UCLA: “The moon is older than scientists thought, UCLA-led research team reports” 

    UCLA bloc

    UCLA

    January 11, 2017
    Stuart Wolpert

    1
    Apollo 14 astronaut Alan Shepard. A new UCLA study determined the age of the moon by analyzing minerals brought back by the 1971 mission. NASA.

    UCLA-led research team reports that the moon is at least 4.51 billion years old, or 40 million to 140 million years older than scientists previously thought.

    The findings — based on an analysis of minerals from the moon called zircons that were brought back to Earth by the Apollo 14 mission in 1971 — are published Jan. 11 in the journal Science Advances.

    The moon’s age has been a hotly debated topic, even though scientists have tried to settle the question over many years and using a wide range of scientific techniques.

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    Mélanie Barboni. Carolyn Crow

    “We have finally pinned down a minimum age for the moon; it’s time we knew its age and now we do,” said Mélanie Barboni, the study’s lead author and a research geochemist in UCLA’s Department of Earth, Planetary and Space Sciences.

    The moon was formed by a violent, head-on collision between the early Earth and a “planetary embryo” called Theia, a UCLA-led team of geochemists and colleagues reported in 2016.

    The newest research would mean that the moon formed “only” about 60 million years after the birth of the solar system — an important point because it would provide critical information for astronomers and planetary scientists who seek to understand the early evolution of the Earth and our solar system.

    That has been a difficult task, Barboni said, because “whatever was there before the giant impact has been erased.” While scientists cannot know what occurred before the collision with Theia, these findings are important because they will help scientists continue to piece together major events that followed it.

    It’s usually difficult to determine the age of moon rocks because most of them contain a patchwork of fragments of multiple other rocks. But Barboni was able to analyze eight zircons in pristine condition. Specifically, she examined how the uranium they contained had decayed to lead (in a lab at Princeton University) and how the lutetium they contained had decayed to an element called hafnium (using a mass spectrometer at UCLA). The researchers analyzed those elements together to determine the moon’s age.

    “Zircons are nature’s best clocks,” said Kevin McKeegan, a UCLA professor of geochemistry and cosmochemistry, and a co-author of the study. “They are the best mineral in preserving geological history and revealing where they originated.”

    The Earth’s collision with Theia created a liquefied moon, which then solidified. Scientists believe most of the moon’s surface was covered with magma right after its formation. The uranium–lead measurements reveal when the zircons first appeared in the moon’s initial magma ocean, which later cooled down and formed the moon’s mantle and crust; the lutetium–hafnium measurements reveal when its magma formed, which happened earlier.

    “Mélanie was very clever in figuring out the moon’s real age dates back to its pre-history before it solidified, not to its solidification,” said Edward Young, a UCLA professor of geochemistry and cosmochemistry and a co-author of the study.

    Previous studies concluded the moon’s age based on moon rocks that had been contaminated by multiple collisions. McKeegan said those rocks indicated the date of some other events, “but not the age of the moon.”

    The UCLA researchers are continuing to study zircons brought back by the Apollo astronauts to study the early history of the moon.

    Co-authors of the Science Advances study are Patrick Boehnke, a former UCLA graduate student who is now a University of Chicago postdoctoral scholar; Christopher Keller, a UC Berkeley postdoctoral scholar; Issaku Kohl, a UCLA research geochemist; and Blair Schoene, associate professor of geosciences at Princeton University.

    The research was funded by NASA, and Barboni received support from the Swiss National Science Foundation.

    See the full article here .

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    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
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