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  • richardmitnick 9:16 pm on September 28, 2014 Permalink | Reply
    Tags: Astronomy, , , , ,   

    From SPACE.com: ” NASA Exoplanet Mission to Hunt Down Earth-sized Worlds” 

    space-dot-com logo


    September 28, 2014
    Nola Taylor Redd

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


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

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

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

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

    NASA Kepler Telescope

    A bounty of Earth-sized extrasolar planets

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

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

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

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

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

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

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

    A wealth of knowledge

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

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

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

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

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

    NASA Webb Telescope

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

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

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

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

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

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

    See the full article, with video, here.

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

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



    Fri, 26 Sep 2014
    Joshua Sokol

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

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

    Carnegie Las Campanas Observatory
    Las Campanas Observatory

    NASA Wise Telescope

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

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

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

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

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

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

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

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

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

    See the full article here.

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

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  • richardmitnick 2:35 pm on September 27, 2014 Permalink | Reply
    Tags: Astronomy, , ,   

    From LLNL: “Giant Steps For Adaptive Optics” 

    Lawrence Livermore National Laboratory

    Science & Technology Review
    september 2014
    Arnie Heller

    LAST November, high in the Chilean Andes, an international team of scientists and engineers, including Lawrence Livermore researchers, celebrated jubilantly in the early morning hours. The cause for their celebration was the appearance of a faint but unmistakable image of a planet 63 light-years from Earth circling a nearby star called Beta Pictoris. The clear image was viewable from a ground-based telescope thanks to one of the most advanced adaptive optics systems in existence, a key element of the newly fielded Gemini Planet Imager (GPI).

    Gemini Planet Imager
    Gmini Planet Imager

    GPI (pronounced gee-pie) is deployed on the 8.1-meter-diameter Gemini South telescope, situated near the summit of Cerro Pachón at an altitude of 2,715 meters. The size of a small car, GPI is mounted behind the primary mirror of the giant telescope. Although the imager is still in its shakedown phase, it is producing the fastest and clearest images of extrasolar planets (exoplanets) ever recorded. GPI is perhaps the most impressive scientific example of Lawrence Livermore’s decades-long preeminence in adaptive optics. This technology uses an observing instrument’s optical components to remove distortions that are induced by the light passing through a turbulent medium, such as Earth’s atmosphere, or by mechanical vibration.

    Gemini South telescope
    Gemini South Interior
    Gemini South Telescope

    More than two decades ago, Livermore scientists were among the first to show how adaptive optics can be used in astronomy to eliminate the effects of atmospheric turbulence, which cause the twinkle we see in stars when viewing them from Earth. Those effects also create blurring in images recorded by ground-based telescopes. Laboratory researchers have since applied adaptive optics to other fields, including lasers and medicine. For example, adaptive optics helped produce extremely high-resolution images of the retina with an instrument that won an R&D 100 Award in 2010. (See S&TR, October/November 2010, A Look inside the Living Eye.) Livermore teams are now working on an adaptive optics system to transport x-ray beams in a new generation of high-energy research facilities. In addition, outreach efforts by the Laboratory are strengthening educational opportunities in this field at U.S. colleges and universities.

    Designed for Exoplanet Imaging

    GPI is the first astronomical instrument designed and optimized for direct exoplanet imaging and analysis. Imaging planets directly is exceedingly difficult because most planets are at least 1 to 10 million times fainter than the parent stars they orbit. One way to improve image quality is to send telescopes into orbit, which boosts research costs enormously. A much less expensive approach is to equip a ground-based telescope with adaptive optics to compensate in real time for the distortions of light caused by Earth’s atmosphere.

    Livermore computational engineer David Palmer, GPI project manager and leader of its adaptive optics development effort, notes that GPI comprises several interconnected systems and components. In addition to adaptive optics, the imager includes an interferometer, coronagraph, spectrometer, four computers, and an optomechanical structure to which everything is attached. All are packaged into an enclosure 2 cubic meters in volume and flanked on either side by “pods” that hold the accompanying electronics.

    GPI hangs on the back end of Gemini South, a design that sharply constrains the imager’s volume, weight, and power requirements. While in use, it constantly faces the high winds and hostile environment at high altitude. As the telescope slews to track a star, the instrument flexes, making alignment more complicated. Nevertheless, says Palmer, GPI has maintained its alignment “phenomenally well” and performed superbly. “The precision requirements worked up by the GPI design team are almost staggering,” he says, “especially those for the adaptive optics system.”

    Laboratory electrical engineer Lisa Poyneer adds, “GPI features several new approaches that enable us to correct the atmosphere with precision never before achieved.” Poyneer developed the algorithms (mathematical procedures) that control two deformable mirrors and led adaptive optics system testing in the laboratory and at the telescope.

    GPI is an international project with former Livermore astrophysicist Bruce Macintosh (now a professor at Stanford University) serving as principal investigator. The Gemini South telescope is an international partnership as well, involving the U.S., Canada, Australia, Argentina, Brazil, and Chile. Macintosh says the first discussions concerning a ground-based instrument dedicated to the search for exoplanets began in 2001. “A lot of exoplanets were being discovered at that time, but the discoveries didn’t tell us much about the planets themselves,” he says. “There was a clear scientific need to incorporate adaptive optics, and the technology was progressing quickly.”

    After more than eight years in development, GPI components were tested and integrated at the Laboratory for Adaptive Optics at the University of California (UC) at Santa Cruz in 2012 and 2013. The imager was shipped to Chile in August 2013, with first light conducted in November.

    Scientists will use GPI over the next three years to discover and characterize dozens or more exoplanets circling stars located up to 230 light-years from Earth. In addition to resolving exoplanets from their parent stars, GPI uses a spectrometer to probe the composition of each exoplanet’s atmosphere. The instrument also studies disks around young stars with a technique called polarization differential imaging.

    Lawrence Livermore engineer Lisa Poyneer (left) and Stanford University astrophysicist Bruce Macintosh (previously at Livermore) stand in front of the Gemini Planet Imager (GPI), which is installed on the Gemini South telescope in Chile. Two electronic pods (blue) on either side of the main enclosure hold GPI’s electronics. (Photograph by Jeff Chilcote, University of California at Los Angeles [UCLA].)

    Age of Exoplanet Discovery

    The discovery of exoplanets was a historic breakthrough in modern astronomy. More than 1,000 exoplanets have been identified, mainly through indirect techniques that infer a planet’s mass and orbit. Astronomers have been surprised by the diversity of planetary systems that differ from our solar system. GPI is expected to strengthen scientific understanding of how planetary systems form and evolve, how planet orbits change, and what comprises their atmospheres.

    GPI masks the light emitted by a parent star to reveal the faint light of young (up to 1-billion-year-old) giant planets in orbits a few times greater than Earth’s path around the Sun. These young gas giants (the size of Jupiter and larger) are detected through their thermal radiation (about 1.0 to 2.4 micrometers wavelength in the near-infrared region).

    GPI is not sensitive enough to see Earth-sized planets, which are 10,000 times fainter than giant planets. (See S&TR, July/August 2012, A Spectra-Tacular Sight.) However, it complements astronomical instruments that infer a planet’s mass and orbit by measuring the small gravitational tugs exerted on a parent star or, as with NASA’s Kepler Space Telescope, by blocking very small amounts of light emitted by the parent star as the planet passes in front of that star. “These indirect methods tell us a planet is there and a bit about its orbit and mass, but not much else,” says Macintosh. “Kepler can detect tiny planets similar to the size of Earth. With GPI, we can find much larger planets, the size of Jupiter, so the two instruments provide complementary information.”

    NASA Kepler Telescope

    The direct imaging of giant planets permits the use of spectroscopy to estimate their size, temperature, surface gravity, and atmospheric composition. Because different molecules absorb light at different wavelengths, scientists can correlate the light emitted from a planet to the molecules in its atmosphere.

    In November 2013, members of the GPI first-light team celebrated when the system acquired its first images. The team includes: (from left to right) Pascale Hibon, Stephen Goodsell, Markus Hartung, and Fredrik Rantakyrö from Gemini Observatory; Jeffrey Chilcote, UCLA; Jennifer Dunn, National Research Council (NRC) Canada Herzberg Institute of Astrophysics; Sandrine Thomas, NASA Ames Research Center; Macintosh; David Palmer, Lawrence Livermore; Dmitry Savransky, Cornell University; Marshall Perrin, Space Telescope Science Institute.; and Naru Sadakuni, Gemini Observatory. (Photograph by Jeff Chilcote, UCLA.)

    In November 2013, members of the GPI first-light team celebrated when the system acquired its first images. The team includes: (from left to right) Pascale Hibon, Stephen Goodsell, Markus Hartung, and Fredrik Rantakyrö from Gemini Observatory; Jeffrey Chilcote, UCLA; Jennifer Dunn, National Research Council (NRC) Canada Herzberg Institute of Astrophysics; Sandrine Thomas, NASA Ames Research Center; Macintosh; David Palmer, Lawrence Livermore; Dmitry Savransky, Cornell University; Marshall Perrin, Space Telescope Science Institute; and Naru Sadakuni, Gemini Observatory. (Photograph by Jeff Chilcote, UCLA.)

    Extreme Adaptive Optics

    The heart of GPI is its highly advanced, high-contrast adaptive optics system (sometimes called extreme adaptive optics) that measures and corrects wavefront errors induced by atmospheric air motion and the inevitable tiny flaws in optics. As light passes through the Gemini South telescope, GPI measures its wavefront 1,000 times per second at nearly 2,000 locations. The system corrects the distortions within 1 millisecond by precisely changing the positions of thousands of actuators, which adjusts the shape of two mirrors. As the adaptive optics system operates, GPI typically takes about 60 consecutive, 1-minute exposures and can detect an exoplanet 70 times more rapidly than existing instruments.

    To meet GPI’s stringent requirements, the Livermore team developed several technologies specifically for exoplanet science. A self-optimizing computer system controls the actuators, with computationally efficient algorithms determining the best position for each actuator with nanometer-scale precision. A spatial filter prevents aliasing (artifacts).

    Livermore optical engineer Brian Bauman designed the innovative and compact adaptive optics for GPI. He has also worked on adaptive optics components for vision science and Livermore’s Atomic Vapor Laser Isotope System and has developed simpler systems for telescopes at the Lick Observatory and other observatories. Says Bauman, “We wanted GPI to provide much greater contrast and resolution than had been achieved in an adaptive optics system without producing artifacts that could mask a planet or be mistaken for one.”

    The system corrects aberrations by adjusting the shape of two deformable mirrors. Incoming light from the telescope is relayed to the first mirror, called the woofer. Measuring about 5 centimeters across, this mirror has 69 actuators to correct atmospheric components with low spatial frequencies.

    The woofer passes the corrected light to the tweeter—a 2.56-centimeter-square deformable mirror with 4,096 actuators for finer corrections. The tweeter is a microelectromechanical systems– (MEMS-) based device developed for GPI by Boston Micromachines. It is made of etched silicon, similar to the material used for microchips, rather than reflective glass. The tweeter’s actuators are spaced only 400 micrometers apart; a circular patch of 44 actuators in diameter is used to compensate for the high-spatial-frequency components of the atmosphere.

    GPI has 10 times the actuator density of a general-purpose adaptive optics system. Poyneer explains that the more actuators, the more accurately the mirror surface can correct for atmospheric turbulence. “MEMS was the only technology that could give us thousands of actuators and meet our space and power requirements,” she says. “Given the number of actuators, we had to design the system to measure all aberrations at the same resolution.” This precision in controlling the mirrors is accomplished by a wavefront sensor that breaks incoming light into smaller subregions, similar to the receptors on a fly’s compound eye.

    A major challenge to the increased number of actuators is that existing algorithms required far too much computation to adjust the mirrors as quickly as needed. In response, Poyneer developed a new algorithm that requires 45 times less computation. “GPI must continually perform all of its calculations within 1 millisecond,” says Palmer, who implemented the real-time software that achieves this goal. Remarkably, the system of algorithms is self-optimized. That is, says Poyneer, “A loop monitors how the operations are going and adjusts the control system every 8 seconds. If the atmospheric turbulence gets stronger, the system control will become more aggressive to give the best performance possible.”

    The mirrors forward the corrected light to a coronagraph, which blocks out much of the light from the parent star being observed, revealing the vastly fainter planets orbiting that star. Relay optics then reform the light onto a lenslet array, and a prism disperses the light into thousands of tiny spectra. The resulting pattern is transferred to a high-speed detector, and a few minutes of postprocessing removes the last remaining noise, or speckles.

    A 2.56-centimeter-square deformable mirror called a tweeter is used for fine-scale correction of the atmosphere. This microelectromechanical systems– (MEMS-) based device has 4,096 actuators and is made of etched silicon, similar to the material used for microchips. (Courtesy of Boston Micromachines.)

    A 2.56-centimeter-square deformable mirror called a tweeter is used for fine-scale correction of the atmosphere. This microelectromechanical systems– (MEMS-) based device has 4,096 actuators and is made of etched silicon, similar to the material used for microchips. (Courtesy of Boston Micromachines.)

    A 2.56-centimeter-square deformable mirror called a tweeter is used for fine-scale correction of the atmosphere. This microelectromechanical systems– (MEMS-) based device has 4,096 actuators and is made of etched silicon, similar to the material used for microchips. (Courtesy of Boston Micromachines.)

    First Light November 2013

    Researchers conducted the first observations with GPI in November 2013, when they trained the Gemini South telescope on two known planetary systems: the four-planet HR8799 system (codiscovered in 2008 by a Livermore-led team at the Gemini and Keck observatories) and the one-planet Beta Pictoris system. A highlight from the November observations was GPI recording the first-ever spectrum of the young planet Beta Pictoris b, which is visible as a small but distinct dot.

    This composite image represents the close environment of Beta Pictoris as seen in near infrared light. This very faint environment is revealed after a very careful subtraction of the much brighter stellar halo. The outer part of the image shows the reflected light on the dust disc, as observed in 1996 with the ADONIS instrument on ESO’s 3.6 m telescope; the inner part is the innermost part of the system, as seen at 3.6 microns with NACO on the Very Large Telescope. The newly detected source is more than 1000 times fainter than Beta Pictoris, aligned with the disc, at a projected distance of 8 times the Earth-Sun distance. Both parts of the image were obtained on ESO telescopes equipped with adaptive optics.
    Date 21 November 2008
    Source http://www.eso.org

    ESO 3.6m telescope & HARPS at LaSilla
    ESO 3.6 M Telescope at Cerro LaSilla

    ESO VLT Interferometer
    ESO VLT at Cerro Paranal

    Keck Observatory
    Keck Observatory Interior

    Using the instrument’s polarization mode, the first-light team also detected starlight scattered by tiny particles and studied a faint ring of dust orbiting the young star HR4796A. The team released the images at the January 2014 meeting of the American Astronomical Society. “The first images were a factor of 10 better than those taken with the previous generation of instruments,” says Macintosh. “We could see a planet in the raw image, which was pretty amazing. In one minute, we found planets that used to take us an hour to detect.”

    Data from the first-light observations are allowing researchers to refine estimates of the orbit and size of Beta Pictoris b. To analyze the exoplanet, the Livermore team and their international collaborators looked at the two disks of dense gas and debris surrounding the parent star. They found that the planet is not aligned with the main debris disk but instead with an inner warped disk, with which it may interact. “If Beta Pictoris b is warping the disk, that helps us see how the planet-forming disk in our own solar system might have evolved long ago,” says Poyneer.

    Since first light, the Livermore adaptive optics team has been working to improve GPI’s performance by minimizing vibration caused by the coolers that chill the spectrometer to a very low temperature. Vibrations decrease the stability of the parent star on the coronagraph and inject a significant focusing error into the system as the telescope optics shake. In response, the team developed algorithms that effectively cancel the errors in a manner similar to noise-canceling headphones. The filters have reduced pointing vibrations to a mere one-thousandth of an arcsecond and decreased the focusing error by 30 times, from 90 to 3 nanometers.

    In November 2014, the GPI Exoplanet Survey—an international team that includes dozens of leading exoplanet scientists—will begin an 890-hour-long campaign to discover and characterize giant exoplanets orbiting 600 young stars. These planets are located between 5 and 50 astronomical units from their parent stars, or up to 50 times the distance of Earth from the Sun (nearly 150 million kilometers). The observing time is the largest amount allocated to one group at Gemini South and represents 10 to 15 percent of the time available for the next three years. In the meantime, GPI verification and commissioning efforts continue.

    (left) During its first observations, GPI captured this image within 60 seconds. It shows a planet orbiting the star Beta Pictoris, which is 63 light-years from Earth. (right) A series of 30 images was later combined to enhance the signal-to-noise ratio and remove spectral artifacts. The four spots equidistant from the star are fiducials, or reference points. (Image processing by Christian Marois, NRC Canada.)

    (left) During its first observations, GPI captured this image within 60 seconds. It shows a planet orbiting the star Beta Pictoris, which is 63 light-years from Earth. (right) A series of 30 images was later combined to enhance the signal-to-noise ratio and remove spectral artifacts. The four spots equidistant from the star are fiducials, or reference points. (Image processing by Christian Marois, NRC Canada.)


    GPI also records data using polarization differential imaging to more clearly capture scattered light. Images of the young star HR4796A revealed a narrow ring around the star, which could be dust from asteroids or comets left behind by planet formation. The left image shows normal light scattered by Earth’s turbulent atmosphere, including both the dust ring and the residual light from the central star. The right image shows only polarized light taken with GPI. (Image processing by Marshall Perrin, Space Telescope Science Institute.)
    GPI also records data using polarization differential imaging to more clearly capture scattered light. Images of the young star HR4796A revealed a narrow ring around the star, which could be dust from asteroids or comets left behind by planet formation. The left image shows normal light scattered by Earth’s turbulent atmosphere, including both the dust ring and the residual light from the central star. The right image shows only polarized light taken with GPI. (Image processing by Marshall Perrin, Space Telescope Science Institute.)

    The Livermore adaptive optics team has improved GPI’s performance by minimizing vibration caused by the coolers that chill the spectrometer. Vibrations inject a large focusing error into the system as the telescope optics shake. The team developed filters that reduced the focusing error by 30 times—from 90 nanometers to 3.

    Adaptive Control of X-Ray Beams

    Building on the adaptive optics expertise gained with GPI, the Laboratory has launched an effort, led by Poyneer, to design, fabricate, and test x-ray deformable mirrors equipped with adaptive optics. “We took some of the best adaptive optics people in the world and put them with our experts in x-ray mirrors,” says physicist Michael Pivovaroff, who initiated the program.

    Livermore researchers previously applied their expertise in x-ray optics to design and fabricate the six advanced mirrors for the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory in Menlo Park, California. These mirrors transport the LCLS x-ray beam and control its size and direction. The brightest x-ray source in the world, LCLS can capture stop-action shots of moving molecules with a “shutter speed” measured in femtoseconds, or million-billionths of a second. With a wavelength about the size of an atom, it can image objects as small as the DNA helix. (See S&TR, January/February 2011, Groundbreaking Science with the World’s Brightest X Rays.)


    Despite the outstanding performance of current x-ray mirrors, further advances in their quality are required to take full advantage of the capabilities of LCLS and newer facilities, such as the Department of Energy’s (DOE’s) National Synchrotron Light Source II at Brookhaven National Laboratory and those under construction in Europe. “DOE is investing billions of dollars building x-ray light sources such as synchrotrons and x-ray lasers,” says Pivovaroff. “Scientists working with those systems need certain spatial and spectral characteristics for their experiments, but every x-ray optic distorts the photons in some way. We don’t want our mirrors to get in the way of the science.”

    nsls II interior

    Combining adaptive optics with x-ray mirrors may lead to three significant benefits. First, active control is a potentially inexpensive way to achieve better surface flatness than is possible by polishing the mirrors alone. Second, the ability to change a mirror’s flatness allows for real-time correction of aberrations in an x-ray beamline. This capability includes self-correction of errors in the mirror itself (such as those caused by heat buildup) and correction of errors introduced by other optics. Finally, adaptive optics–corrected x-ray mirrors could widen the possible attributes of x-ray beams, leading to new kinds of experiments.

    Unlike mirrors used at visible and near-infrared wavelengths, x-ray mirrors must operate at a shallow angle called a grazing incidence. This requirement makes their design and profile quite different from deformable mirrors for astronomy. Traditional x-ray optics are rigid and have a longitudinal, or ribbon, profile up to 1 meter long. If adaptive optics systems can be designed to correct distortions in x-ray beams, next-generation research facilities could offer greater experimental flexibility and achieve close to their theoretical performance.

    “As with visible and infrared light, we want to manipulate the x-ray wavefront with mirrors while preserving coherence,” says Livermore optical engineer Tom McCarville, who was lead engineer for the LCLS x-ray mirrors. “The fabrication tolerances are much greater because x-ray wavelengths are so short. Technologies for diffracting and transmitting x rays are relatively limited compared to those available for visible light. Reflective x-ray technology is, however, mature enough to deploy for transporting x rays from source to experiment. Dynamically controlling the mirror’s surface figure will preserve the x-ray source’s properties during transport and thus enhance the precision of experimental results.”

    Extremely small adjustments to the surface height on the x-ray deformable mirror correct the incoming beam, as depicted in this artist’s rendering (not to scale). Unlike visible light, the x rays can only be reflected off the mirror at a very shallow incoming angle, called a grazing incidence. (Rendering by Kwei-Yu Chu.)

    First X-Ray Deformable Mirror

    With funding from the Laboratory Directed Research and Development (LDRD) Program, the Livermore team designed and built the first grazing-incidence adaptive optics x-ray mirror with demonstrated performance suitable for use at high-intensity DOE light sources. This x-ray deformable mirror, developed with partner Northrop-Grumman AOA Xinetics, was made from a superpolished single-crystal silicon bar measuring 45 centimeters long, 30 millimeters high, and 40 millimeters wide, the same dimensions of the three hard x-ray mirrors built for LCLS.

    A single row of 45 actuators bonded opposite the reflecting surface makes the mirror deformable. These 1-centimeter-wide actuators provide fine-scale control of the mirror’s surface figure (overall shape). Actuators respond to voltage changes by expanding or contracting in width along the mirror’s long axis to bend the reflecting surface. Seven internal temperature sensors and 45 strain gauges monitor the silicon bar, providing a method to self-correct for long-term drifts in the surface figure.

    As with all x-ray optics, the quality of the mirror’s surface is extremely important because the slightest bump or imperfection will scatter x rays. The substrate was thus fabricated and superpolished to nanometer-scale precision before assembly into a deformable mirror. The initial surface figure error for the deformable mirror was 19 nanometers. Although extremely small, it is substantially above the 1-nanometer-level required for best performance in an x-ray beamline.

    To meet that requirement, the team used high-precision visible light measurements of the mirror’s surface to “flatten” the mirror. With this approach, interferometer measurements are processed with specialized control algorithms. Specific voltages are then applied to the actuators to adjust the mirror’s surface. The resulting figure error was only 0.7 nanometers. “We demonstrated the first subnanometer active flattening of a substrate longer than 15 centimeters,” says Poyneer. “It was a very important step in validating our technological approach.”

    For deformable mirrors to be fully effective, scientists must develop better methods to analyze the x-ray beamline. “We need a sensor that won’t distort the beam,” says Pivovaroff. Such a sensor would provide a feedback loop that continuously feeds beam characteristics to the mirror actuators so they compensate for inconsistencies in the beam. Poyneer is working on new diagnostic techniques at Lawrence Berkeley National Laboratory’s Advanced Light Source (ALS), and the Livermore team is scheduled to begin testing the mirror on a beamline at ALS. The long-term goal of that testing will be to repeat the subnanometer flattening experiment, this time using x rays to measure the surface.

    Poyneer is hopeful the adaptive optics research effort will eventually result in a national capability that DOE next-generation x-ray light sources can draw on for new beamlines. She has shared the results with scientists at several DOE high-energy research centers and is working to better understand the needs of beamline engineers and the scientists who use those systems. “There’s a lot of interest and excitement in the community because deformable mirrors let us do better science,” says Pivovaroff. “The performance of our mirror has surprised many people. Controlling the surface of a half-meter-long optic to less than a nanometer is quite an accomplishment.”

    By enabling delivery of more coherent and better-focused x rays, the mirrors are expected to produce sharper images, which could lead to advances in physics, chemistry, and biology. The technology may enable new types of x-ray diagnostics for experiments at the National Ignition Facility.

    In an experiment, high-precision visible light measurements were used to flatten the x-ray deformable mirror to a surface figure error of only 0.7 nanometers average deviation.

    This artist’s concept illustrates the difference in reconstruction quality that adaptive optics could provide if installed at next-generation x-ray beamline facilities. At the top, a partially coherent x-ray beam hits the target object, producing a diffraction pattern on the detector and limiting the accuracy of the recovered image. At the bottom, adaptive optics provide a coherent beam with excellent wavefront quality, which improves resolution of the object. (Rendering by Kwei-Yu Chu.)

    Expanded Educational Outreach

    The Laboratory’s adaptive optics team is also dedicated to training the next generation of scientists and engineers for careers in adaptive optics and is working to disseminate expertise in adaptive optics technology to academia and industry. In a joint project between Lawrence Livermore National Security (the managing contractor for Lawrence Livermore) and UC, two graduate students from the UC Santa Cruz Department of Astronomy and Astrophysics are testing advanced algorithms that could further improve the performance of systems such as GPI. The algorithms are designed to predict wind-blown turbulence and further negate the effects of the atmosphere. Poyneer and astronomer Mark Ammons are mentoring the students, Alex Rudy and Sri Srinath.

    Poyneer says, “GPI has demonstrated how continued work on technology developments can lead to significantly improved instrument performance.” According to Ammon, “An important frontier in astronomy is pushing adaptive optics operation to visible wavelengths, which requires better control. GPI routinely meets these stringent performance requirements.”

    The lessons learned as part of the GPI experience will be critical input for next-generation adaptive optics on large telescopes, such as the W. M. Keck telescopes in Hawaii. Ammons adds, “While adaptive optics were first developed for military purposes, the loop has now closed—the advances made with GPI offer a wide range of potential applications for national security applications.”

    In addition, the Livermore team is applying its expertise to other fields, as exemplified by progress in the extremely flat x-ray deformable mirror. Thanks to adaptive optics, the universe—from planets to x rays—is coming into greater focus.

    See the full article here.

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

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

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

    UCO Lick Observatory
    UCO Lick Observatory

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

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

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

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

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

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

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

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

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

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

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  • richardmitnick 2:40 pm on September 26, 2014 Permalink | Reply
    Tags: Astronomy, , , , Extraterrestrials, ,   

    From Seth Shostak at SETI Institute: “So What Really Goes Down if We Find the Aliens?” 

    SETI Institute

    September 26, 2014
    By Seth Shostak, Senior Astronomer and Director of the Center for SETI Research

    SETI Seth Shostak
    Seth Shostak

    If we trip across life that’s not of this world, do we blast it or befriend it? What impact would it have on our society?

    This was the topic of a two-day symposium held at the John W. Kluge Center of the Library of Congress last week. Several dozen researchers — astronomers, philosophers, theologians, biologists, historians, and other tweed-jacketed specialists — opined on what might happen should we find we’re not alone.

    A lot of the discussion, unsurprisingly, was about discovering life that’s intelligent. This prompted a symposium leitmotiv that was dished out repeatedly: when thinking about aliens, beware of anthropocentrism. In other words, don’t assume that they will be similar to us ethically, culturally, or cognitively.

    Well sure, I can get down with that. I agree that we tend to view everything in the universe through the prism of our own natures. Mind you, I note that the squirrels in my front yard seem to do the same. They’re awfully squirrel-centric. That ensures that they attend to activities that are truly important (mostly acorn management). I don’t think less of them for that.

    Where this leitmotiv became more than a neo-Greek caution against hubris was when it was used to argue that SETI (the Search for Extraterrestrial Intelligence) is fatally flawed. We were told that our hunt for aliens assumes that they are like us. That kind of provincial attitude, it was said, will doom SETI to endless frustration. If we don’t think outside our own biological box, we’ll fail to find any company in the cosmos.

    But wait a minute: That’s akin to arguing that the 1976 Viking landers — with their complex instrumentation for sensing microbial Martians — were a clear non-starter because they were sensitive to carbon-based metabolism; in other words, life as we know it. Well, that’s true, but it was really hard to design experiments that were good at finding life as no-one-knows-it.

    Actually, when it comes to SETI experiments, we try not to make assumptions about the aliens’ cultural, ethical, or even biological makeup. We don’t assume they are similar to us. Rather, we assume that their physics is similar to ours — that they use radio transmitters or lasers to send information from wherever they are to wherever they need it. That’s no more anthropocentric than assuming that — if aliens use ground transportation — at least some of it is on wheels.

    Anthropocentrism is always a bugaboo, but to say that it might irretrievably cripple our efforts to find evidence for intelligence elsewhere is certainly arguable. So let’s consider that SETI experiments are not as myopic as some would aver. The big question then becomes, what happens if we pick up a ping?

    First, allow me to dispense with the false, but nonetheless ever-popular idea that the public wouldn’t be told. That’s goofier than Big Bird, and easily disproved by a cursory reference to SETI’s occasional false alarms. This paranoid idea probably derives from the widespread claim that 67 years ago some wayward aliens made a dismaying navigational error, and piloted their craft into the dirt near Roswell, New Mexico. The fact that this event is not the subject of much investigation by research scientists is often explained as the consequence of a government cover-up. The feds don’t want you to know about extraterrestrials.

    One could make the same argument about the lack of academic interest in leprechauns. Maybe the Irish government is hiding the bodies. I don’t find that a compelling argument. But I think the popular notion of secret evidence sparks the mistaken belief that a SETI detection would be hushed up. It won’t be.

    Of greater relevance to the subject of this symposium — preparing for discovery — was what would the signal reveal? What could we learn about the senders’ construction or culture?

    The most plausible answer is “not much.” Just as hearing a rustle in the forest provides precious little information on the flora or fauna that caused it, so too would an alien ping be largely uninformative, at least at first. There might be an accompanying message, but new and different instruments would be required to find it.

    What we could learn quickly are a few, mostly astronomical facts, to wit: (1) How far away is their solar system; (2) What type of star do they orbit? (3) The length of their day and their year.

    That might be it for a while. And “a while” would be years, at minimum.

    If we find intelligent beings elsewhere in our galaxy, you’ll not be quickly confronted with complex philosophical problems of understanding their mode of thinking or their biological blueprint — or even knowing whether they are biological. You won’t be misled by anthropocentric thinking, because there will be precious little information about whether they’re like us or not. For years, all we’ll be able to say is that there’s something out there that’s at least as technologically competent as we are.

    But of course, that’s still saying a lot.

    See the full article here.

    SETI Institute – 189 Bernardo Ave., Suite 100
    Mountain View, CA 94043
    Phone 650.961.6633 – Fax 650-961-7099
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  • richardmitnick 1:21 pm on September 26, 2014 Permalink | Reply
    Tags: Astronomy, , , , ESO MOONS   

    From ESO: “ESO Signs Agreement to Build MOONS” 

    European Southern Observatory

    26 September 2014
    Peter Hammersley
    ESO, MOONS Project Manager
    Garching bei München, Germany
    Tel: +49 89 3200 6772
    Email: phammers@eso.org

    Dietrich Baade
    ESO, MOONS Project Scientist
    Garching bei München, Germany
    Tel: +49 89 3200 6388
    Email: dbaade@eso.org

    Michele Cirasuolo
    MOONS Principal Investigator
    UK Astronomy Technology Centre, Royal Observatory
    Edinburgh, United Kingdom
    Email: ciras@roe.ac.uk

    Richard Hook
    ESO, Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    ESO has signed an agreement with a consortium led by the Science and Technology Facilities Council’s UK Astronomy Technology Centre (UK ATC) to build MOONS — a unique new instrument for ESO’s Very Large Telescope (VLT). MOONS will be able to tackle some of the most compelling astronomical questions such as probing the structure of the Milky Way and tracing how stars and galaxies form and evolve. During its ten-year design lifetime, MOONS is expected to observe of order ten million objects.



    MOONS [1] stands for Multi-Object Optical and Near-infrared Spectrograph. This complex instrument will collect light from many objects at the same time, using up to 1000 fibres over a large field of view, and will work at both visible light and near-infrared wavelengths. The power of the VLT, combined with the unique capabilities of MOONS, will provide the tools necessary to study galaxy formation and evolution over most of the history of the Universe [2].

    As well as studies of the distant Universe, the infrared capabilities of MOONS will allow astronomers to study the highly obscured regions of the bulge of our galaxy. In combination with the power of the VLT, it will observe stars within the Milky Way up to a distance of about 40 000 light-years, looking through the Bulge and Disc to reveal their structure to create a three-dimensional map of our galaxy [3].

    In 2010, ESO asked for suggestions from its community for a wide-field spectrometer. Two concepts, MOONS (Multi-Object Optical and Near-infrared Spectrograph) and 4MOST (4-metre Multi-Object Spectroscopic Telescope) were reviewed in 2013 and selected to proceed to a design and construction phase with MOONS scheduled for first light in 2018 and 4MOST in 2019.

    MOONS will also provide the crucial spectroscopic follow-up for the European Space Agency (ESA)’s Gaia mission and for other ground based optical and near-infrared imaging surveys (VISTA, UKIDSS, VST, Pan-STARRS, Dark Energy Survey, LSST), as well as facilities operating at other wavelengths (ALMA, Herschel, eRosita, LOFAR, WISE, ASKAP). As such, it will fill a critical gap in the astronomical toolkit, particularly in the near-infrared.

    MOONS will also play an important role for the recently approved ESA mission Euclid, covering the same spectral range as its space observations and will support its calibration. It will perfectly complement ongoing and planned surveys including the new large Gaia–ESO public spectro­scopic survey [4], where optical spectroscopy is being performed by FLAMES and VIMOS.

    [1] The MOONS project brings together scientists and engineers in a consortium led by the Science and Technology Facilities Council – UK Astronomy Technology Centre, Royal Observatory, Edinburgh, United Kingdom; and including CAAUL – Centre for Astronomy and Astrophysics of University of Lisbon, Portugal; GEPI, Observatoire de Paris, France; Italian National Institute for Astrophysics (INAF) with its centres in Florence, Bologna, Milan and Rome, Italy; AIUC, Centre for Astro-Engineering, Pontificia Universidad Católica de Chile, Santiago Chile; Cavendish Laboratory and Institute of Astronomy, University of Cambridge, United Kingdom; ETH Zürich, Institute for Astronomy, Switzerland; the University of Geneva, through its Astronomical Observatory, Sauverny, Switzerland and ESO.

    [2] A very strong scientific case for the development of a wide-field, spectrometer that could observe many objects simultaneously at both visible and near-infrared wavelengths has existed for many years and was a high priority of ASTRONET — a comprehensive long-term plan for the development of European astronomy. Such an instrument is considered much-needed to complement existing wide-field imaging surveys.

    ASTRONET was created by a group of European funding agencies in order to establish a strategic planning mechanism for all of European astronomy and it has published a comprehensive science vision and infrastructure roadmap.

    [3] This is difficult because the Earth is in the middle of the disc of the Milky Way, so the process is a little like trying to map a forest from the inside.

    [4] Gaia-ESO is an ESO public spectroscopic survey, targeting more than 100 000 stars with the FLAMES optical multi-fibre spectrograph, systematically covering all major components of the Milky Way, from halo to star-forming regions.

    See the full article here.

    Visit ESO in Social Media-




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  • richardmitnick 9:17 pm on September 25, 2014 Permalink | Reply
    Tags: Astronomy, , , ,   

    From Ethan Siegel: “From Nothing to You in Ten Sentences” 

    Starts with a bang
    Starts with a Bang

    Sep 25, 2014

    “It surprises me how disinterested we are today about things like physics, space, the universe and philosophy of our existence, our purpose, our final destination. It’s a crazy world out there. Be curious.” -Stephen Hawking

    Stephen Hawking

    One of the most existential questions humanity has ever asked is the question of our origins: where do I come from? Inspired by Ben Kilminster’s writings, here’s the entire history of the Universe — that’s led up to the existence of you — in just 10 sentences.*

    Image credit: Amber Stuver of http://www.livingligo.org/.

    1.) At some point in the distant past**, the Universe consisted of empty spacetime with a large amount of intrinsic energy bound up in itself, and was in a state of exponential expansion known as cosmological inflation.

    Image credit: me.

    2.) About 13.8 billion years ago, a region of spacetime that would contain our entire observable Universe saw inflation come to an end, as the energy that was bound up in spacetime itself was transferred*** into matter, antimatter and radiation.

    Image credit: Retrieved from http://case.ntu.edu.tw/hs/wordpress/?p=41808.

    3.) The energetic, matter-antimatter-and-radiation-filled Universe now cools as it expands, and a fundamental asymmetry**** between matter-and-antimatter leads to a slight, 0.6-parts-in-a-billion dominance of matter over antimatter.

    Image credit: me, with the background by Brian Smallwood.

    4.) As the Universe continues to expand cool, the excess matter annihilates away with the antimatter, leaving only a little bit of matter behind, while the radiation shifts to progressively lower energies, allowing the formation of protons and neutrons, stable nuclei, and eventually neutral, stable atoms.

    The quark structure of the proton. The color assignment of individual quarks is arbitrary, but all three colors must be present. Forces between quarks are mediated by gluons.

    The quark structure of the neutron. The color assignment of individual quarks is arbitrary, but all three colors must be present. Forces between quarks are mediated by gluons

    Image credit: Universe Adventure, © 2005 LBNL Physics Division.

    5.) With the Universe now dominated by matter, gravitational collapse proceeds, and the great cosmic web begins to form, with the first stars in the Universe igniting after a period of 50-to-75 million years.

    Image credit: Kfir Simon / Demetrius Gore, via http://www.pbase.com/tango33/image/140317019/original..

    6.) The light from these stars reionizes the Universe, making it transparent to light, while the Universe hierarchically forms star clusters, galaxies, clusters, and attempts to form galactic superclusters on the largest scales.

    Map of voids and superclusters within 500 million light years from Milky Way
    Date 08/11/09
    Source http://www.atlasoftheuniverse.com/nearsc.html
    Author Richard Powell

    Image credit: Jim Misti (Misti Mountain Observatory).

    7.) As time goes on, the most massive stars run out of fuel and die in supernova explosions, triggering the formation of new stars and enriching the surrounding interstellar media with progressively heavier and heavier elements.

    Image credit: NASA/JPL-Caltech/L. Rudnick (University of Minnesota), via http://www.spitzer.caltech.edu/images/1675-ssc2006-19a-Lighting-up-a-Dead-Star-s-Layers.

    8.) After multiple generations of stars are born, live, burn through their fuel and die, the interstellar medium contains enough of the elements for complex chemistry that all new stars and star systems that form will have substantial amounts of the elements and molecules necessary for life.

    Image credit: NASA, ESA, CXC, SSC, and STScI.

    9.) About 9.2 billion years after the Big Bang, a small region about 25,000 light years from the center of our Milky Way forms a new cluster of around a thousand stars, one of which — out of the hundreds of billions in our galaxy — forms with a protoplanetary disk that collapses into eight planets: four rocky inner worlds and four outer gas giants.

    Image credit: Avi M. Mandell, NASA.

    10.) After a few hundred million years, complex, self-reproducing chemical life takes off***** on the third world in this solar system, and a vast diversity of lifeforms evolve over billions of years and trillions of generations, when a chance joining of two cells culminates in 10^28 of those atoms coming together to exist as you.

    Image credit: Ernst Haeckel’s Paleontological Tree of Vertebrates (c. 1879).

    And that’s how the Universe came from nothing, to create you, in just 10 (not even run-on) sentences!******

    • – Not every aspect of how each of these events happened is fully understood. The asterisks are here to show you the events that are currently still being investigated.

    ** – It is not clear how the Universe came to be in this state, and whether that state was eternal to the past or whether it came into existence in some fashion.

    *** – The particulars of how inflation ended (the “graceful exit” problem) and how the energy was transferred into matter, antimatter and radiation (the “cosmic reheating” problem) do not presently have universally agreed-upon answers.

    **** – We don’t know the exact mechanism of what caused the observed asymmetry between matter and antimatter; an illustrative example is here.

    ***** – We don’t know whether life originated on this world or on another world or in interstellar space; we only know that it took off on this world some 3+ billion years ago.

    ****** – Fine, ten sentences, eleven images and six footnotes.

    See the full article here.

    Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible.

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  • richardmitnick 4:24 pm on September 25, 2014 Permalink | Reply
    Tags: , Astronomy, , , , ,   

    From SPACE.com: “Newfound Molecule in Space Dust Offers Clues to Life’s Origins” 

    space-dot-com logo


    September 25, 2014
    Megan Gannon

    The discovery of a strangely branched organic molecule in the depths of interstellar space has capped a decades-long search for the carbon-bearing stuff.

    The organic molecule iso-propyl cyanide has a branched carbon backbone (i-C3H7CN, left), unlike its straight-chain isomer normal-propyl cyanide (n-C3H7CN, right). Both molecules were detected with ALMA in Sagittarius B2. Credit: MPIfR/A. Weiss, University of Cologne/M. Koerber, MPIfR/A. Belloche

    The molecule in question — iso-propyl cyanide (i-C3H7CN) — was spotted in Sagittarius B2, a huge star-making cloud of gas and dust near the center of the Milky Way, about 27,000 light-years from the sun. The discovery suggests that some of the key ingredients for life on Earth could have originated in interstellar space.

    A specific molecule emits light at a particular wavelength and in a telltale pattern, or spectrum, which scientists can detect using radio telescopes. For this study, astronomers used the enormous Atacama Large Millimeter/submillimeter Array (ALMA) telescope in the Chilean desert, which went online last year and combines the power of 66 radio antennas.

    ALMA Array
    ALMA Array

    Iso-propyl cyanide joins a long list of molecules detected in interstellar space. But what makes this discovery significant is the structure of iso-propyl cyanide. All other organic molecules that have been detected in space so far (including normal-propyl cyanide, the sister of i-C3H7CN) are made of a straight chain with a carbon backbone. Iso-propyl cyanide, however, has a “branched” structure. This same type of branched structure is a key characteristic of amino acids.

    “Amino acids are the building blocks of proteins, which are important ingredients of life on Earth,” the study’s lead author, Arnaud Belloche, of the Max Planck Institute for Radio Astronomy, told Space.com in an email. “We are interested in the origin of amino acids in general and their distribution in our galaxy.”

    The central region of the Milky Way can be seen above the antennas of the ALMA observatory in Chile.

    Scientists have previously found amino acids in meteorites that fell to Earth, and the composition of these chemicals suggested they had an interstellar origin. The researchers in this new study did not find amino acids, but their discovery adds an “additional piece of evidence that the amino acids found in meteorites could have been formed in the interstellar medium,” Belloche wrote.

    “The detection of a molecule with a branched carbon backbone in interstellar space, in a region where stars are being formed, is interesting because it shows that interstellar chemistry is indeed capable of producing molecules with such a complex, branched structure,” Belloche added.

    It was first suggested in the 1980s that branched molecules could form on the surface of dust grains in interstellar space. But this is the first time such compounds have been detected. What’s more, iso-propyl cyanide seemed to be plentiful — it was almost half as abundant of its more common sister variant in Sagittarius B2, the study found. This means that branched molecules could actually be quite ordinary in interstellar space, the researchers said.

    The research is detailed in the Sept. 26 edition of the journal Science.

    See the full article here.

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  • richardmitnick 4:08 pm on September 25, 2014 Permalink | Reply
    Tags: Astronomy, , , , ,   

    From SPACE.com: “Much of Earth’s Water Is Older Than the Sun” 

    space-dot-com logo


    September 25, 2014
    Mike Wall

    Much of the water on Earth and elsewhere in the solar system likely predates the birth of the sun, a new study reports.

    Planets form in the presence of abundant interstellar water inherited as ices from the parent molecular cloud.
    Credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech)/ESO/J. Emerson/VISTA/Cambridge Astronomical Survey Unit

    The finding suggests that water is commonly incorporated into newly forming planets throughout the Milky Way galaxy and beyond, researchers said — good news for anyone hoping that Earth isn’t the only world to host life.

    “The implications of our study are that interstellar water-ice remarkably survived the incredibly violent process of stellar birth to then be incorporated into planetary bodies,” study lead author Ilse Cleeves, an astronomy Ph.D. student at the University of Michigan, told Space.com via email.

    “If our sun’s formation was typical, interstellar ices, including water, likely survive and are a common ingredient during the formation of all extrasolar systems,” Cleeves added. “This is particularly exciting given the number of confirmed extrasolar planetary systems to date — that they, too, had access to abundant, life-fostering water during their formation.”

    Astronomers have discovered nearly 2,000 exoplanets so far, and many billions likely lurk undetected in the depths of space. On average, every Milky Way star is thought to host at least one planet.

    Artist’s concept showing the time sequence of water ice, starting in the sun’s parent molecular cloud, traveling through the stages of star formation, and eventually being incorporated into the planetary system itself.
    Credit: Bill Saxton, NSF/AUI/NRAO

    Water, water everywhere

    Our solar system abounds with water. Oceans of it slosh about not only on Earth’s surface but also beneath the icy shells of Jupiter’s moon Europa and the Saturn satellite Enceladus. And water ice is found on Earth’s moon, on comets, at the Martian poles and even inside shadowed craters on Mercury, the planet closest to the sun.

    Cleeves and her colleagues wanted to know where all this water came from.

    “Why is this important? If water in the early solar system was primarily inherited as ice from interstellar space, then it is likely that similar ices, along with the prebiotic organic matter that they contain, are abundant in most or all protoplanetary disks around forming stars,” study co-author Conel Alexander, of the Carnegie Institution for Science in Washington, D.C., said in a statement.

    “But if the early solar system’s water was largely the result of local chemical processing during the sun’s birth, then it is possible that the abundance of water varies considerably in forming planetary systems, which would obviously have implications for the potential for the emergence of life elsewhere,” Alexander added.

    Heavy and ‘normal’ water

    Not all water is “standard” H2O. Some water molecules contain deuterium, a heavy isotope of hydrogen that contains one proton and one neutron in its nucleus. (Isotopes are different versions of an element whose atoms have the same number of protons, but different numbers of neutrons. The most common hydrogen isotope, known as protium, for example, has one proton but no neutrons.)

    Because they have different masses, deuterium and protium behave differently during chemical reactions. Some environments are thus more conducive to the formation of “heavy” water — including super-cold places like interstellar space.

    The researchers constructed models that simulated reactions within a protoplanetary disk, in an effort to determine if processes during the early days of the solar system could have generated the concentrations of heavy water observed today in Earth’s oceans, cometary material and meteorite samples.

    The team reset deuterium levels to zero at the beginning of the simulations, then watched to see if enough deuterium-enriched ice could be produced within 1 million years — a standard lifetime for planet-forming disks.

    The answer was no. The results suggest that up to 30 to 50 percent of Earth’s ocean water and perhaps 60 to 100 percent of the water on comets originally formed in interstellar space, before the sun was born. (These are the high-end estimates generated by the simulations; the low-end estimates suggest that at least 7 percent of ocean water and at least 14 percent of comet water predates the sun.)

    While these findings, published online today (Sept. 25) in the journal Science, will doubtless be of interest to astrobiologists, they also resonated with Cleeves on a personal level, she said.

    “A significant fraction of Earth’s water is likely incredibly old, so old that it predates the Earth itself,” Cleeves said. “For me, uncovering these kinds of direct links between our daily experience and the galaxy at large is fascinating and puts a wonderful perspective on our place in the universe.”

    See the full article here.

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  • richardmitnick 1:12 pm on September 25, 2014 Permalink | Reply
    Tags: Astronomy, , , ,   

    From Daily Galaxy: “Hubble Captures a Newly Formed Galaxy in Our Cosmic Neighborhood” 

    Daily Galaxy
    The Daily Galaxy

    September 25, 2014
    No Writer Credit


    Elderly galaxies tend to be larger thanks to collisions and mergers with other galaxies that have bulked them out, and are populated with a variety of different types of stars — including old, young, large, and small ones. Their chemical makeup is different too. Newly-formed galaxies have a similar composition to the primordial matter created in the Big Bang (hydrogen, helium and a little lithium), while older galaxies are enriched with heavier elements forged in stellar furnaces over multiple generations of stars.
    Dwarf galaxy DDO 68, captured by the NASA/ESA Hubble Space Telescope, was one of the best candidates so far discovered for a newly-formed galaxy in our cosmic neighborhood. The galaxy lies around 39 million light-years away from us; although this distance may seem huge, it is in fact roughly 50 times closer than the usual distances to such galaxies, which are on the order of several billions of light years.

    NASA Hubble Telescope
    NASA/ESA Hubble

    Astronomers usually have to peer very far into the distance to see back in time, and view the Universe as it was when it was young. This new NASA/ESA Hubble Space Telescope image of galaxy DDO 68, otherwise known as UGC 5340, was thought to offer an exception. This ragged collection of stars and gas clouds looks at first glance like a recently-formed galaxy in our own cosmic neighbourhood. But, is it really as young as it looks?

    Astronomers have studied galactic evolution for decades, gradually improving our knowledge of how galaxies have changed over cosmic history. The NASA/ESA Hubble Space Telescope has played a big part in this, allowing astronomers to see further into the distance, and hence further back in time, than any telescope before it — capturing light that has taken billions of years to reach us.

    Looking further into the very distant past to observe younger and younger galaxies is very valuable, but it is not without its problems for astronomers. All newly-born galaxies lie very far away from us and appear very small and faint in the images. On the contrary, all the galaxies near to us appear to be old ones.

    By studying galaxies of various ages, astronomers have found that those early in their lives are fundamentally different from those that are older. DDO 68 looks to be relatively youthful based on its structure, appearance, and composition. However, without more detailed modelling astronomers cannot be sure and they think it may be older than it lets on.

    DDO 68 is the best representation yet of a primordial galaxy in the local Universe as it appears at first glance to be very low in heavier elements — whose presence would be a sign of the existence of previous generations of stars.

    Local Group

    Hubble observations were carried out in order to study the properties of the galaxy’s light, and to confirm whether or not there are any older stars in DDO 68. If there are, which there seem to be, this would disprove the hypothesis that it is entirely made up of young stars. If not, it would confirm the unique nature of this galaxy. More complex modelling is needed before we can know for sure but Hubble’s picture certainly gives us a beautiful view of this unusual object.

    The image is made up of exposures in visible and infrared light taken with Hubble’s Advanced Camera for Surveys.

    NASA Hubble ACS
    Hubble ACS

    See the full article here.

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