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  • richardmitnick 9:07 am on August 31, 2015 Permalink | Reply
    Tags: Astronomy, , NASA CYGNUS, ,   

    From NASA SpaceFlight: “Enhanced Cygnus to help Orbital ATK meet CRS contract by 2017” 

    NASA Spaceflight

    NASA Spaceflight

    August 31, 2015
    Chris Gebhardt

    NASA CYGNUS
    CYGNUS

    The first flight of Orbital ATK’s Enhanced Cygnus resupply craft for the International Space Station is set to launch in December atop an Atlas V rocket. Helping Orbital ATK return to flight operations, the Enhanced Cygnus spacecraft will allow the company to meet their initial CRS cargo up-mass contract with NASA in just four more missions.

    December’s upcoming OA-4 mission of Cygnus to the International Space Station (ISS) will be the first flight of Cygnus under the newly merged company Orbital ATK and the first flight of the company’s resupply vehicle on a non-Antares rocket.

    The OA-4 mission will be lofted to orbit on a United Launch Alliance Atlas V rocket launching from the Cape Canaveral Air Force Station, FL.

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    United Launch Alliance Atlas V rocket

    Cygnus’ ingrained adaptability to launch on rockets other than Antares has allowed Orbital ATK to purchase an Atlas V rocket for the OA-4 mission and, in turn, gain significant up-mass capability on the OA-4 mission than would have been possible launching on Antares.

    This additional up-mass capability supported by the powerful Atlas V rocket’s core stage and its Centaur upper stage will allow Orbital ATK to reach a major milestone in the company’s Commercial Resupply Contract (CRS) with NASA sooner than expected.

    In an exclusive interview with NASASpaceflight.com, Frank DeMauro, CRS Program Director for Orbital ATK stated that “with the upgraded Antares 230 and then with the couple of Atlas V [missions], we’re actually going to meet our initial cargo delivery requirement through the OA7 mission.”

    While Enhanced Cygnus on an Atlas V is part of what will allow Orbital ATK to meet their cargo delivery up-mass requirement on the OA-7 mission instead of the OA-8 mission, the enhanced version of Cygnus was planned from the inception of the program and is not a change stemming from the Orb-3 launch failure in October 2014.

    According to Mr. DeMauro, “we had planned from the beginning of the program that there would actually be two versions of Cygnus.”

    The first variant, the Standard Cygnus, flew on all three previous Orbital CRS ISS missions (including October’s failed Orb-3 CRS mission) in 2014 as well as the predecessor COTS Demo flight of Cygnus to ISS in Sept. 2013.

    The Standard Cygnus, flying on Orbital’s Antares 110, 120, and 130 series rockets, could carry a maximum payload of approximately 2,000 kg (4,400 lbs) to ISS.

    Enhanced Cygnus, on Atlas V, will be capable of lifting a maximum payload of 3,500 kg (7,700 lbs) to the ISS and 3,200 kg (7,100 lbs) of payload to ISS on the Antares 230 series rocket — set to debut early next year as part of Orbital ATK’s return to flight path.

    According to Mr. DeMauro, “we had planned a long time ago that we would start flying, on the fourth mission, a longer cargo module — with essentially more volume to carry more cargo.”

    NASA Enhanced CYGNUS
    NASA Enhanced CYGNUS

    In fact, Enhanced Cygnus will have a stretched Pressurized Cargo Module (PCM) that will increase the total interior PCM volume to 27 cubic meters — an increase from the 18 cubic meter PCM volume of the Standard Cygnus.

    Moreover, the stretched PCM is not the only aspect of the Enhanced Cygnus that will debut on December’s OA-4 flight. Orbital ATK ultraflex solar arrays will also grace the Enhanced Cygnus later this year.

    “One of the more visible changes was the change-out from the flat panel solar array to an Orbital ATK ultraflex solar array — which deploys sort of like a fan,” stated Mr. DeMauro.

    “The biggest difference between [the Orbital ATK ultraflex array] and a more traditional array is the structure behind the cells. It’s essentially a lightweight material to which the cells are mounted, as opposed to a more heavy structure.

    “The key is to develop the array in such a way that you have a small stowed package with a highly reliable deployment system, but that when it’s open, the amount of surface area you get is about the same as you would get from a regular flat panel area.”

    This approach to the Enhanced Cygnus design will allow Orbital ATK to have a lower mass solar array that produces the same amount of power as the previous generation Cygnus solar arrays.

    Importantly, though, the visual changes of the Enhanced Cygnus aren’t the only improvements Orbital ATK has made to its ISS resupply craft.

    Lessons learned in terms of loading cargo into Cygnus have led to a significant increase in the amount of cargo that can be arranged within Cygnus.

    According to Mr. DeMauro, “As we learned other things we could do in the cargo module, we’ve actually significantly increased the amount of cargo we can load in the same volume on the Enhanced Cygnus.

    “So that’s why you’re seeing, for a relatively low percentage of size increase of the PCM, a significant increase in cargo carrying capability.”

    With its introduction on the OA-4 mission in December, Enhanced Cygnus will become the only variant of Cygnus used for ISS resupply missions through the completion of Orbital ATK’s CRS contract with NASA — a contract that was recently extended by three missions.

    Following the OA-7 mission in 2016, the OA-8E, OA-9E, and OA-10E missions will launch between 2017 and the first part of 2018.

    Those added missions will continue to focus solely on Cygnus’ pressurized up-mass capability to ISS.

    When asked about possible Cygnus variants to allow for external cargo deliveries to ISS, Mr. DeMauro stated that Orbital ATK’s “focus right now and moving forward is on pressurized up-mass and pressurized disposal.

    “What we do, what NASA is counting on us to do, is to deliver as much pressurized up-mass as possible. And then also, very importantly, the removal of disposal cargo from inside the Station.”

    Mr. DeMauro specifically noted that this service from Cygnus compliments the other contracted services NASA has for Station resupply efforts, and that there are no plans to redesign Cygnus for external supply delivery ops at Station.

    If the current schedule holds, the first Enhanced Cygnus will launch to the ISS atop an Atlas V rocket – flying in the 401 configuration (with a 4-meter fairing, zero solid rocket boosters, and a single-engine Centaur upper stage) – on 3 December 2015 during a launch window that opens at 17:55 EST and closes at 18:25 EST (22:55 – 23:25 GMT).

    See the full article here.

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    NASASpaceFlight.com, now in its eighth year of operations, is already the leading online news resource for everyone interested in space flight specific news, supplying our readership with the latest news, around the clock, with editors covering all the leading space faring nations.

    Breaking more exclusive space flight related news stories than any other site in its field, NASASpaceFlight.com is dedicated to expanding the public’s awareness and respect for the space flight industry, which in turn is reflected in the many thousands of space industry visitors to the site, ranging from NASA to Lockheed Martin, Boeing, United Space Alliance and commercial space flight arena.

    With a monthly readership of 500,000 visitors and growing, the site’s expansion has already seen articles being referenced and linked by major news networks such as MSNBC, CBS, The New York Times, Popular Science, but to name a few.

     
  • richardmitnick 3:24 pm on August 28, 2015 Permalink | Reply
    Tags: Astronomy, , , DKIST   

    From AURA: “The UK in DKIST” 

    AURA Icon
    Association of Universities for Research in Astronomy

    UK Solar Physics

    August 17, 2015
    Lyndsay Fletcher University of Glasgow
    Mihalis Mathioudakis Queen’s University Belfast
    Erwin Verwichte University of Warwick
    On behalf of the UK DKIST consortium members.

    Introduction

    The Daniel K. Inouye Solar Telescope [DKIST] is a 4m ground-based solar telescope currently under construction on the Haleakala mountain on the island of Maui, Hawai’i. It will be the largest solar telescope in the world by some way, with a diffraction limit a factor 3 smaller than that of any existing solar telescope. The UK has now joined the DKIST project, providing the cameras for four of the DKIST instruments. The UK DKIST consortium is financed by the Science and Technology Facilities Council, 8 UK universities, and Andor Technology plc. This nugget gives an overview of the DKIST, the UK’s contribution, and the opportunities for all UK solar physicists to get involved.

    DKIST telescope
    DKIST

    The DKIST is led by the US National Solar Observatory (NSO) with funding from the National Science Foundation (NSF). It will operate in the optical and near-infrared and will be the pre-eminent ground-based solar telescope for the foreseeable future. Its adaptive optics will enable diffraction-limited observations with a spatial resolution of 25 km, less than the photon scattering mean-free path in the photosphere — a fundamental physical scale in the visible. It is located at an altitude of 3,000 m on Haleakala, Hawaii, giving the very low scattered light necessary for coronal studies. The DKIST first light will be in 2019, and it will serve the solar physics community to 2050 and beyond.

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    Fig 1: The main structural elements of the DKIST dome being installed; the basket on the crane gives an idea of the scale. Source NSO/DKIST.

    The DKIST’s main science goals are:

    What are the building blocks of solar magnetism?
    How is magnetic energy built up, released and transported in flares and CMEs?
    What is the origin of solar variability?

    The key advances in the DKIST’s first-light instruments, which will be used to address these questions, are ultra-high spatial resolution (25 km) and ultra-high time cadence (10’s of ms) imaging, high resolution photospheric and chromospheric imaging spectroscopy and vector magnetometry, plus infrared coronal magnetometry.

    2
    Fig 2: The chromosphere in He 304 from AIA at 1.2″ resolution (right) and the same view in H-alpha from IBIS equipped with a ROSA camera (left) at 0.25″ spatial resolution (click for full resolution). The improvement in spatial resolution offered by DKIST will be about the same again. Image credit: Kevin Reardon PhD (NSO/QUB).

    As a highly sophisticated facility, DKIST will normally be operated in service mode by expert astronomers on behalf of the PIs of observing proposals – like a ‘spacecraft on the ground’. The telescope has five first-generation instruments: VBI -the Visible Broadband Imager; VTF – the Visible Tunable Filter; ViSP – the Visible Spectro-Polarimeter; DL-NIRSP -the Diffraction Limited Near Infra-Red Spectro-Polarimeter and Cryo-NIRSP the Cryogenic Near Infra-Red Spectro-Polarimeter. The first light instrument will be the VBI, for which the UK’s ROSA imager is the prototype. Light from the primary can be shared between the first four of the five listed instruments simultaneously, allowing enormous flexibility in operations and thus science investigations. The Cryo-NIRSP instrument focuses on diagnostics of the faint corona, and will observe by itself, taking advantage of an unobstructed aperture and best coronal seeing conditions. Full details of the instruments can be found here.

    The UK Consortium

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    Fig 3: The UK DKIST consortium institutes

    The UK DKIST consortium is led by Queen’s University Belfast, and involves 7 other institutes (Armagh, Glasgow, MSSL, Northumbria, Sheffield, St. Andrews and Warwick). Finance for the consortium has been provided by the STFC, by the UK institutes involved, and Andor Technology plc who are investing internal resources in the camera development. The consortium will provide 9 identical cameras for four instruments on the DKIST, and in return the UK will have some guaranteed access time to the DKIST (in addition to competitively awarded open time). The consortium will also develop and implement aspects of the data analysis toolkit and help members of the UK community become involved with the DKIST science plan, and preparation of observations.

    How to get involved

    The UK DKIST consortium was formed for the benefit of the whole UK Solar Physics Community; it is not necessary to be working at one of the Consortium institutes to propose for observing time. However, the Consortium does aim to co-ordinate UK activities in DKIST, and to provide assistance with understanding the telescope, the instruments, and the process of preparing a proposal. There are two main ways that you can currently get involved;

    Contribute data processing, analysis or forward-modelling software (contact Erwin Verwichte)
    Contribute to the DKIST Critical Science Plan, and propose for observations (contact Lyndsay Fletcher)

    Some of the DKIST’s science topics are described in the science cases. The UK DKIST consortium will be adopting the process for developing DKIST proposals outlined in the critical science plan.
    Conclusions

    The DKIST is an exciting new facility that will address many science questions of interest to the UK solar community. It will be able to work in co-ordination with ESA’s Solar Orbiter, though this will take very careful planning. We encourage the UK community to start developing their ideas for ground-breaking new science with the DKIST.

    See the full article here.

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  • richardmitnick 2:59 pm on August 28, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From NASA: “NASA’s New Horizons Team Selects Potential Kuiper Belt Flyby Target” 

    NASA

    NASA

    Aug. 28, 2015
    Editor: Tricia Talbert

    1
    Artist’s impression of NASA’s New Horizons spacecraft encountering a Pluto-like object in the distant Kuiper Belt. Credits: NASA/JHUAPL/SwRI/Alex Parker

    NASA has selected the potential next destination for the New Horizons mission to visit after its historic July 14 flyby of the Pluto system.

    NASA New Horizons spacecraft
    New Horizons

    The destination is a small Kuiper Belt object (KBO) known as 2014 MU69 (formerly labeled 1110113Y in the context of the Hubble Space Telescope, and 11 and PT1 in the context of the New Horizons mission) that orbits nearly a billion miles beyond Pluto.

    1
    An annotated overlay of 5 Hubble Space Telescope Wide Field Camera 3 images of 2014 MU69 taken on June 24, 2014.

    3
    Kuiper Belt

    This remote KBO was one of two identified as potential destinations and the one recommended to NASA by the New Horizons team. Although NASA has selected 2014 MU69 as the target, as part of its normal review process the agency will conduct a detailed assessment before officially approving the mission extension to conduct additional science.

    “Even as the New Horizon’s spacecraft speeds away from Pluto out into the Kuiper Belt, and the data from the exciting encounter with this new world is being streamed back to Earth, we are looking outward to the next destination for this intrepid explorer,” said John Grunsfeld, astronaut and chief of the NASA Science Mission Directorate at the agency headquarters in Washington. “While discussions whether to approve this extended mission will take place in the larger context of the planetary science portfolio, we expect it to be much less expensive than the prime mission while still providing new and exciting science.”

    Like all NASA missions that have finished their main objective but seek to do more exploration, the New Horizons team must write a proposal to the agency to fund a KBO mission. That proposal – due in 2016 – will be evaluated by an independent team of experts before NASA can decide about the go-ahead.

    Early target selection was important; the team needs to direct New Horizons toward the object this year in order to perform any extended mission with healthy fuel margins. New Horizons will perform a series of four maneuvers in late October and early November to set its course toward 2014 MU69 – nicknamed “PT1” (for “Potential Target 1”) – which it expects to reach on January 1, 2019. Any delays from those dates would cost precious fuel and add mission risk.

    “2014 MU69 is a great choice because it is just the kind of ancient KBO, formed where it orbits now, that the Decadal Survey desired us to fly by,” said New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute (SwRI) in Boulder, Colorado. “Moreover, this KBO costs less fuel to reach [than other candidate targets], leaving more fuel for the flyby, for ancillary science, and greater fuel reserves to protect against the unforeseen.”

    New Horizons was originally designed to fly beyond the Pluto system and explore additional Kuiper Belt objects. The spacecraft carries extra hydrazine fuel for a KBO flyby; its communications system is designed to work from far beyond Pluto; its power system is designed to operate for many more years; and its scientific instruments were designed to operate in light levels much lower than it will experience during the 2014 MU69 flyby.”

    The 2003 National Academy of Sciences’ Planetary Decadal Survey (“New Frontiers in the Solar System”) strongly recommended that the first mission to the Kuiper Belt include flybys of Pluto and small KBOs, in order to sample the diversity of objects in that previously unexplored region of the solar system. The identification of PT1, which is in a completely different class of KBO than Pluto, potentially allows New Horizons to satisfy those goals.

    But finding a suitable KBO flyby target was no easy task. Starting a search in 2011 using some of the largest ground-based telescopes on Earth, the New Horizons team found several dozen KBOs, but none were reachable within the fuel supply available aboard the spacecraft.

    The powerful Hubble Space Telescope came to the rescue in summer 2014, discovering five objects, since narrowed to two, within New Horizons’ flight path. Scientists estimate that PT1 is just under 30 miles (about 45 kilometers) across; that’s more than 10 times larger and 1,000 times more massive than typical comets, like the one the Rosetta mission is now orbiting, but only about 0.5 to 1 percent of the size (and about 1/10,000th the mass) of Pluto. As such, PT1 is thought to be like the building blocks of Kuiper Belt planets such as Pluto.

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    Path of NASA’s New Horizons spacecraft toward its next potential target, the Kuiper Belt object 2014 MU69, nicknamed “PT1” (for “Potential Target 1”) by the New Horizons team. NASA must approve any New Horizons extended mission to explore a KBO. Credits: NASA/JHUAPL/SwRI/Alex Parker

    Unlike asteroids, KBOs have been heated only slightly by the Sun, and are thought to represent a well preserved, deep-freeze sample of what the outer solar system was like following its birth 4.6 billion years ago.

    “There’s so much that we can learn from close-up spacecraft observations that we’ll never learn from Earth, as the Pluto flyby demonstrated so spectacularly,” said New Horizons science team member John Spencer, also of SwRI. “The detailed images and other data that New Horizons could obtain from a KBO flyby will revolutionize our understanding of the Kuiper Belt and KBOs.”

    The New Horizons spacecraft – currently 3 billion miles [4.9 billion kilometers] from Earth – is just starting to transmit the bulk of the images and other data, stored on its digital recorders, from its historic July encounter with the Pluto system. The spacecraft is healthy and operating normally.

    New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Ala. The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.

    See the full article here.

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    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 12:06 pm on August 28, 2015 Permalink | Reply
    Tags: Astronomy, , , ,   

    From SPACE.com: “How to Find ‘Strange Life’ on Alien Planets” 

    space-dot-com logo

    SPACE.com

    August 28, 2015
    Nola Taylor Redd

    1
    This artist’s rendition of the super-Earth GJ 1214b shows it in orbit around a dim red dwarf star. If the atmosphere is thick in hydrogen, scientists may be able to spot signs of alien life. Credit: CfA/David Aguilar

    Detecting signs of life very different from that of Earth in the atmospheres of alien planets may be difficult, but it is possible, researchers say.

    A team of scientists examined models of “super-Earths” — exoplanets slightly larger than Earth — to determine how easily signs of life could be spotted. They determined that such biosignatures could be identified more easily on planets orbiting stars producing relatively low amounts of radiation — but even then only if everything worked out just right.

    The team, led by Sara Seager of the Massachusetts Institute of Technology (MIT), did not focus solely on Earth-like life.

    “What we’ve been trying to do is move away from that,” William Bains, also of MIT, said during the Astrobiology Science Conference in Chicago in June. Bains worked with Seager and Renyu Hu to study super-Earths with hydrogen-rich atmospheres. “We wanted to build a model of biosignatures independent of Earth’s biology.”

    ‘A dynamic process’

    Super-Earths are worlds up to 10 times more massive than our planet. Because of their size, they are more likely to retain an atmosphere rich in molecular hydrogen. The girth of super-Earths also makes them easier to discover, and their atmospheres easier to characterize, relative to their Earth-size cousins. Hydrogen-rich super-Earths are now known to be quite common throughout the galaxy.

    Bains and his colleagues simulated a planet 10 times as massive and nearly twice as wide as Earth, with an atmosphere rich in molecular hydrogen. Their simulations placed the planet in an orbit around three different types of stars: a sunlike star, a normal red dwarf (a star smaller and dimmer than the sun) and and an especially inactive red dwarf. (Different stellar types produce different levels of ultraviolet radiation, with the sunlike star producing the most, which affects how molecules break down in the atmosphere of orbiting planets.)

    To search for biosignatures, Bains said, it’s important to understand why forms of life produce gas in the first place. Some gas is produced as a byproduct when energy is captured from the atmosphere. Other gases are byproducts of metabolic reactions, such as photosynthesis. The third type is created by life not as a result of its central chemical production but from stress, for signaling and in other functions.

    “Life is a dynamic process,” Bains said.

    The byproducts of life

    After determining what gases could survive in the atmosphere, the scientists then calculated how much biomass would be needed to produce a detectable amount, and whether or not such an amount of life would be reasonable to find.

    The team found four volatiles that would be generated by the production of energy in a hydrogen-rich atmosphere. Of them, three could be formed geologically, making them unreliable biosignatures.

    “This was really disappointing,” Bains said.

    The only interesting biosignature that the team came up in the first class was ammonia (NH3). For ammonia to be created, life would have to find a way to break the bonds between molecular nitrogen and molecular hydrogen. On Earth, synthetic chemistry can break each molecule apart individually, but no known system is capable of breaking both at once. Still, the team remains hopeful that a form of life could evolve on other worlds capable of capitalizing on the possibility.

    Producing a detectable amount of ammonia in the atmosphere of a distant super-Earth would require a layer of life less than one bacterial cell thick, researchers said.

    “Even if it was deader than the deadest place on Earth, we could detect it,” Bains said.

    That’s the case for super-Earths orbiting sunlike stars, anyway. For alien planets receiving lower levels of ultraviolet radiation, such as those orbiting standard or quiet red dwarfs, the required biomass would need to be significantly higher.

    While scientists should be able to detect ammonia in the atmosphere of distant planets, determining if it stems from life is another matter. At present, uncertainties about the size and mass of exoplanets remain high enough that worlds presently thought to be super-Earths could, in fact, be mini-Neptunes, gas giants smaller than those found in the solar system.

    Disregarding the fact that surface conditions on gas planets would be essentially nonexistent, the deep atmospheres could produce ammonia without the aid of life. Determining whether a planet is a super-Earth or a mini-Neptune requires probing atmospheric pressures near the surface, something that even NASA’s upcoming James Webb Space Telescope [JWST] will be unable to accomplish, researchers said.

    NASA Webb Telescope
    JWST

    Even if scientists could conclusively identify a planet as rocky, it’s possible that the world could have collected ammonia during its evolution, as Saturn’s moon, Titan, did. Ices on the surface could break down with either internal heat or with the help of ultraviolet radiation, releasing ammonia into the atmosphere to create a false positive.

    So, without getting up close to these distant worlds, characterizing whether ammonia in the atmosphere comes from life remains a significant challenge.

    The research that formed the basis of Bains’ talk at the astrobiology conference was published in late 2013 in The Astrophysical Journal.

    ‘In our favor’

    Seager, Bains and Hu also considered another group of gases — those produced for biomass building. Capturing energy from the environment requires energy. On Earth, a prime example is the oxygen plants release during the process of photosynthesis.

    Unfortunately, the team was unable to identify any potentially useful biosignature gases of this type in a hydrogen-rich atmosphere. The gases that life might produce would be expected to exist naturally in the atmosphere of such a world, Bains said.

    As a third option, the team examined molecules produced unrelated to energy generation. The presence of such gases would depend on the amount of ultraviolet (UV) radiation in the atmosphere, because high UV levels lead to the creation of lots of destructive hydrogen ions.

    Planets orbiting sunlike stars, which emit lots of UV light, would therefore need an enormous density of biomass to produce biosignatures high enough to reach detectable levels. Even around a normal red dwarf, the values would need to be high, though they could be plausible when compared to Earth’s biomass surface density range.

    According to the team, the James Webb Space Telescope (JWST) could spot evidence of biosignatures gas “if and only if every single factor is in our favor.”

    Detecting life using JWST would require a pool of transiting planets around nearby red dwarfs. Because the stars are so dim, they would need to be relatively close to Earth in order for scientists to study their planets. These planets would need a molecular hydrogen atmosphere, which would be easier to study than a more Earth-like atmosphere. The star itself would need to be quiet, with little radiation. Finally, the planet itself must have life that produces a detectable gas as a biosignature.

    “We will have the ability to predict some biosignatures gas independent of Earth,” Bains said. “But it’s going to be really hard to detect.”

    See the full article here.

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  • richardmitnick 11:13 am on August 28, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From SPACE.com- ” Incredible Technology: How to See a Black Hole” Very Old, But Very Worth Your Time 

    space-dot-com logo

    SPACE.com

    July 08, 2013
    Clara Moskowitz

    1
    Theoretical calculations predict that the Milky Way’s central black hole, called Sagittarius A*, will look like this when imaged by the Event Horizon Telescope. The false-color image shows light radiated by gas swirling around and into a black hole. The dark region in the middle is the “black hole shadow,” caused by the black hole bending light around it.
    Credit: Dexter, J., Agol, E., Fragile, P. C., McKinney, J. C., 2010, The Astrophysical Journal, 717, 1092.

    Black holes are essentially invisible, but astronomers are developing technology to image the immediate surroundings of these enigmas like never before. Within a few years, experts say, scientists may have the first-ever picture of the environment around a black hole, and could even spot the theorized “shadow” of a black hole itself.

    Black holes are hard to see in detail because the large ones are all far away. The closest supermassive black hole is the one thought to inhabit the center of the Milky Way, called Sagittarius A* (pronounced “Sagittarius A-star”), which lies about 26,000 light-years away.

    1
    Sagittarius A*. This image was taken with NASA’s Chandra X-Ray Observatory. Ellipses indicate light echoes.
    Date 23 July 2014

    NASA Chandra Telescope
    NASA/Chandra

    This is the first target for an ambitious international project to image a black hole in greater detail than ever before, called the Event Horizon Telescope (EHT).

    Event Horizon Telescope
    Event Horizon Telescope map
    EHT and EHT Map

    The EHT will combine observations from telescopes all over the world, including facilities in the United States, Mexico, Chile, France, Greenland and the South Pole, into one virtual image with a resolution equal to what would be achieved by a single telescope the size of the distance between the separated facilities.

    “This is really an unprecedented, unique experiment,” said EHT team member Jason Dexter, an astrophysical theorist at the University of California, Berkeley. “It’s going to give us more direct information than we’ve ever had to understand what happens extremely close to black holes. It’s very exciting, and this project is really going to come of age and start delivering amazing results in the next few years.”

    From Earth, Sagittarius A* looks about as big as a grapefruit would on the moon. When the Event Horizon Telescope is fully realized, it should be able to resolve details about the size of a golf ball on the moon. That’s close enough to see the light emitted by gas as it spirals in toward its doom inside the black hole.

    Very long baseline interferometry

    To accomplish such fine resolution, the project takes advantage of a technique called very long baseline interferometry (VLBI). In VLBI, a supercomputer acts as a giant telescope lens, in effect.

    “If you have telescopes around the world you can make a virtual Earth-sized telescope,” said Shep Doeleman, an astronomer at MIT’s Haystack Observatory in Massachusetts who’s leading the Event Horizon Telescope project. “In a typical telescope, light bounces off a precisely curved surface and all the light gets focused into a focal plane. The way VLBI works is, we have to freeze the light, capture it, record it perfectly faithfully on the recording system, then shift the data back to a central supercomputer, which compares the light from California and Hawaii and the other locations, and synthesizes it. The lens becomes a supercomputer here at MIT.”

    A major improvement to the Event Horizon Telescope’s imaging ability will come when the 64 radio dishes of the ALMA (Atacama Large Millimeter/submillimeter Array) observatory in Chile join the project in the next few years.

    ALMA Array
    ALMA Array

    “It’s going to increase the sensitivity of the Event Horizon Telescope by a factor of 10,” Doeleman said. “Whenever you change something by an order of magnitude, wonderful things happen.”

    Very long baseline interferometry has been used for about 50 years, but never before at such a high frequency, or short wavelength, of light. This short-wavelength light is what’s needed to achieve the angular resolution required to measure and image black holes.

    South Pole Telescope [SPT]

    The South Pole Telescope will join the Event Horizon Telescope project in coming years to image the area around the black hole at the center of the Milky Way.

    South Pole Telescope
    SPT

    Grand technical challenge

    Pulling off the Event Horizon Telescope has been a grand technical challenge on many fronts.

    To coordinate the observations of so many telescopes spread out around the world, scientists have needed to harness specialized computing algorithms, not to mention powerful supercomputers. Plus, to accommodate the time difference between the various stations, extremely accurate clocks are needed.

    See the full article here.

    Additional:
    Event Horizon Telescope
    Event Horizon Telescope Science

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  • richardmitnick 7:43 pm on August 27, 2015 Permalink | Reply
    Tags: Astronomy, , , Building a CubeSat   

    From ASU: “How a university went into space: ASU’s story” 

    ASU Bloc

    ASU

    August 27th, 2015
    Scott Seckel

    1
    A Mars rover replica at ASU. The university has played roles in 25 missions to eight planets, three asteroids, two moons and the sun.
    Photo by: ASU

    Only 30 institutions in the United States can build spacecraft. Only seven build interplanetary spacecraft that leave Earth’s orbit.

    Arizona State University is one of them.

    ASU’s space program is in elite company. And this week’s CubeSat mission announcement adds to the university’s stellar resume: It will be the first time ASU will lead an interplanetary science expedition.

    It’s not the university’s first outing by a long shot, however.

    ASU has played roles in 25 missions to eight planets, three asteroids, two moons and the sun.

    The School of Earth and Space Exploration was created in 2006. As an institution however, ASU’s space program started much longer ago. This is the story of how a traditional geology program merged with the astronomy side of the physics department and grew into a powerhouse that builds spacecraft.

    Rocks and fighter jocks

    ASU’s space exploration origins lie in the quest to send men to the moon in the 1960s. Ron Greeley, one of the founders of planetary geology, was working at NASA, helping select landing sites for the Apollo missions and assisting in geologic training for astronauts.

    Back in the Apollo days, science was incidental to missions. Engineers – who just wanted to put boots on the moon – frequently clashed with scientists, who wanted to do at least a few things as long as we were going all that way.

    One famous story illustrating the rift centered on a geologist who suggested a rock hammer be included in an astronaut’s tool bag. “But we took one of those on the last mission!” an engineer exploded.

    Early astronauts tended to be fighter jocks who weren’t much interested in rocks either. Greeley succeeded in educating them to be more sophisticated than simply describing rocks as big or little, and how to differentiate between an interesting rock and a more prosaic sample.

    “He was trying to get them to think about the geology and the rocks and what to look for when they got to the moon,” said Phil Christensen, a Regents Professor of geological sciences in ASU’s School of Earth and Space Exploration. “If you listen to the transcripts of those astronauts, Ron and others who trained them did a fantastic job. There were a few (astronauts) who were classic test pilots, Navy guys on an adventure and, oh, I picked up a few rocks. Most of them did a good job.”

    In 1977, Greeley was hired at ASU and focused his research on data from early robotic NASA missions. He received a number of honors during his career, from an asteroid named for him (30785 Greeley) in 1988 to numerous NASA awards.

    From rocks to gadgets

    If Greeley was the father of ASU’s space program, Christensen is the founder of what the program has become.

    Back in 1981, Greeley hired Christensen as a young postdoc who was starting to get involved in space missions. Christensen won a big NASA grant to put an instrument on one of the Mars orbiters.

    He’s since become a Regents Professor (top tenured faculty who have made significant contributions to their field) and is the director of the Mars Space Flight Facility in SESE.

    Greeley was a brilliant field geologist and planetary scientist, but he wasn’t an instrument guy, Christensen said.

    “Ron was a pioneer in looking at the data that came back from these probes, looking at images of the moon and Mars and analyzing them, thinking about them,” he said. “He had no interest in building the instruments, building the cameras, building the spectrometers. … He was on the team, he had access to the data, he was a leader in the field, but he was mostly looking at data that existed and doing the usual science. That’s what ASU did. They didn’t build anything.”

    And when Christensen won a huge contract to build an instrument in the early 1980s, hardly anyone jumped for joy. In fact, the reaction was nervousness and wondering where to put them.

    Christensen asked an associate dean for office space.

    “He said, “Well, there’s a couple of filing cabinets you can have.’ They just didn’t get it. We had this 10, 20 million dollar contract. It was the biggest contract ASU had ever done. They had no idea how to do it. They had no idea how to deal with an aerospace company. So to go from someone offering me two file cabinets to (the current space program and state-of-the-art facilities) … there’s been a lot of changes at this university. It’s been really amazing to watch this grow.”Jim Bell is a professor in SESE, the deputy principal investigator of the LunaH-Map CubeSat mission, and director of the NewSpace Initiative at ASU.

    4
    LunaH-Map CubeSat

    The latter is a program that connects students and faculty doing space-related work with outside entities doing the same thing. They range “from SpaceX to a couple of teenagers in a garage,” Bell said. “Where do they need our help? Can you do a mission for 1 percent of the cost of a big NASA mission?” (They don’t know the answer to that yet.)

    Until now, ASU’s space program has revolved around making instruments that are snapped up by NASA. ASU faculty have been involved with all of NASA’s robotic missions.

    “NASA knows us scientifically, but also from an engineering standpoint,” said Bell, who has built several cameras currently on Mars or in space.

    And that is because of Christensen and Greeley.

    “Those two guys were part of the bedrock foundation of the NASA work here at ASU,” Bell said.

    How to woo NASA

    In the early 1980s, NASA picked the University of Arizona to run a Mars mission. That university asked Christensen if he could build an instrument for it.

    At the same time, defense contractor Raytheon shut down the Santa Barbara facility where Christensen had been working for ASU. Three or four of his colleagues became available. He thought if they came in, and ASU helped out, an instrument could be built at ASU. The instrument they wanted was very similar to one they had already built.

    “It was a perfect storm,” Christensen said. “We were one instrument that was part of a bigger project. It wasn’t a huge risk to NASA to pick the UofA to run this mission and one of the instruments will be built at ASU. It was very similar to what we’d built before. … It was fortuitous that everything came together just right.”

    They worked their tails off for five years.

    “This was a one-shot deal,” Christensen said. “Reputation works both ways. If we screw this up, they’re never going to talk to ASU again. Fifteen people on this project took that really seriously. Not just their careers; ASU had spent a lot of money on this building and these facilities. There was a lot riding on us succeeding. People took a lot of pride in this succeeding. And it did.”

    The campus where spacecraft are built

    ASU had no place to build instruments or spacecraft when Christensen landed at the university in the early 1980s.

    “Now we can build a NASA flight-quality instrument in this building,” he said. “Ten years ago we would have laughed: ‘We can’t do that. We don’t have the facilities, the people, the credibility.’ But we’ve done it. And now because of that, people are coming to me to build them instruments for Europa and other missions.

    NASA Europa
    NASA/Europa

    Jim Bell can say we can build and test cameras here. We have new faculty coming in. Ten years from now there will be several people building instruments in this building. ASU will eventually win a Discovery-class mission.”

    NASA’s Discovery missions are low-cost missions within the solar system with narrow focus. (Cost is relative in space. Discovery missions still cost what an average person would consider a vast sum, but they’re cheap compared with anything involving people being present.)

    “A NASA mission is 90 percent about the process,” Christensen said. “How do you do it? How do you make it work? All things you have to do, all the people working together, keeping them together, keeping them from killing each other – to me that’s half the fun. … Within NASA, like a lot of other places, it’s all about reputation. Can you do it? Once you can, that’s a huge step. Suddenly you’re building more, and people come because of that. It sort of mushrooms.”

    And the university’s physical investment in its space program has come a long way from two battered filing cabinets.

    The 300,000-square-foot Interdisciplinary Science & Technology Building IV (or ISTB4, in local parlance) opened in 2012. It boasts labs, clean rooms, offices, high bays, a 250-seat auditorium and one of two mission operations centers on campus.

    “My colleagues at any other institution come here and they’re jealous,” Christensen said. Last week a Jet Propulsion Lab delegation met with Christensen at the space building. They were jealous, too.

    “It takes money to make money,” Christensen said. “You build a facility like this, it pays for itself. NASA does not want you building stuff out of spit and baling wire. When they come here and see this, they say, ‘You guys are for real.’ ”

    Incidentally, 40 countries can build spacecraft, but only four can build interplanetary spacecraft. That puts ASU ahead of most countries in that aspect.

    The clean rooms in the ASU space building are about the size of a small high school gym.

    “That’s where we’ll build the (LunaH-Map) spacecraft,” Bell said.

    It has the usual desks, monitors and chairs. What isn’t usual are the two vacuum chambers, one the size of a packing crate and the other about the size of a Volkswagen bus. They’re used to simulate space conditions. The lab team can crank all the oxygen out of the chamber, drop the temperature down to absolute zero (minus 459.67 degrees Fahrenheit), and see how what they’ve built stands up to space conditions.

    “You turn it into outer space,” Bell said. “It’s pretty rare for a college campus (to be able to test instruments in that environment). Only a handful of campuses around the country have that capability. Typically you only find that in NASA centers and big aerospace companies.”

    Working together beating things up

    Space system engineer Jekan Thanga came to ASU two years ago, attracted by the school and the space program. He specializes in robots, artificial evolution, exploration of extreme environments, and CubeSats, the small spacecraft like the one ASU is sending to the moon. (He is the chief engineer on the project.)

    The institute’s collaborative nature drew Thanga here. It’s not a conventional aerospace environment. A scientist can walk down the hall, tell an engineer like Thanga he needs to get data from somewhere really nasty and inaccessible, and the engineer can figure out how to make a machine that will go there, survive and get the data home.

    “To the engineering world, it’s a radical departure,” Thanga said. “There is determination here.”

    Thanga and his team spend a lot of time in the clean rooms. They have put machines inside the vacuum chambers, thrown in a bunch of dust and rocks, and cranked them up to see how they fared. (If you were in put it, your eyeballs would pop, the blood in your veins would boil, and eventually you’d boil away. Outer space is a tough place.)

    It’s not uncommon to come in to the clean rooms at 7 a.m. on a Saturday morning and find grad students working on projects. About 15 to 20 people are working on all aspects of design and development at any given time.

    The cutting edge of space exploration

    It’s a far cry from the ’60s, when engineers fought scientists. Now they are in the same building, unseparated by distance or bureaucratic walls.

    “The cutting edge of space exploration is that it’s not good enough to just tell somebody to go build a camera and show up and use it later,” Bell said. “You really have to have your goals in mind while that instrument is on paper. You really have to dive in and become an optics expert. I’ve got to work with optics experts and electrical engineers and all that because I want to make a certain measurement to a certain level of accuracy in a certain environment.

    “The more I can partner with people who understand the engineering and the guts of the electronics, the better my experiments will be. Building those people into the department that is my home at the university is just incredibly efficient and wonderful.”

    Mars rocks

    Some 40 years after Greeley’s time, NASA comes to ASU’s door.

    “When you do things well – really, really well – people notice,” Christensen said. “It’s not just me. ‘Oh, ASU can build those instruments.’ And that flows over to Jim and Craig (Hardgrove, principal investigator on the lunar CubeSat mission) and Erik (Asphaug, working on how to perform a CAT scan on a comet) and Linda (Elkins-Tanton, school director). We’ve built ASU’s reputation.”

    The Mars Rover helped a lot too, he said.

    “Being world leaders in something as visible as exploring Mars got a lot of attention to ASU that leveraged a lot of things going on here now,” Christensen said. “A lot of science is fabulous but, I’m sorry, landing on Mars is not the same as discovering a new type of plastic for Coke bottles; OK, great. Landing on Mars gets you on the cover of magazines.”

    See the full article here.

    Please help promote STEM in your local schools.

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    ASU is the largest public university by enrollment in the United States.[11] Founded in 1885 as the Territorial Normal School at Tempe, the school underwent a series of changes in name and curriculum. In 1945 it was placed under control of the Arizona Board of Regents and was renamed Arizona State College.[12][13][14] A 1958 statewide ballot measure gave the university its present name.
    ASU is classified as a research university with very high research activity (RU/VH) by the Carnegie Classification of Institutions of Higher Education, one of 78 U.S. public universities with that designation. Since 2005 ASU has been ranked among the Top 50 research universities, public and private, in the U.S. based on research output, innovation, development, research expenditures, number of awarded patents and awarded research grant proposals. The Center for Measuring University Performance currently ranks ASU 31st among top U.S. public research universities.[15]

    ASU awards bachelor’s, master’s and doctoral degrees in 16 colleges and schools on five locations: the original Tempe campus, the West campus in northwest Phoenix, the Polytechnic campus in eastern Mesa, the Downtown Phoenix campus and the Colleges at Lake Havasu City. ASU’s “Online campus” offers 41 undergraduate degrees, 37 graduate degrees and 14 graduate or undergraduate certificates, earning ASU a Top 10 rating for Best Online Programs.[16] ASU also offers international academic program partnerships in Mexico, Europe and China. ASU is accredited as a single institution by The Higher Learning Commission.

    ASU Tempe Campus
    ASU Tempe Campus

     
  • richardmitnick 3:17 pm on August 27, 2015 Permalink | Reply
    Tags: Astronomy, , ,   

    From CfA: “Interstellar Seeds Could Create Oases of Life” 

    Smithsonian Astrophysical Observatory
    Smithsonian Astrophysical Observatory

    August 27, 2015
    Christine Pulliam
    Media Relations Manager
    Harvard-Smithsonian Center for Astrophysics
    617-495-7463

    1

    We only have one example of a planet with life: Earth. But within the next generation, it should become possible to detect signs of life on planets orbiting distant stars. If we find alien life, new questions will arise. For example, did that life arise spontaneously? Or could it have spread from elsewhere? If life crossed the vast gulf of interstellar space long ago, how would we tell?

    New research by Harvard astrophysicists shows that if life can travel between the stars (a process called panspermia), it would spread in a characteristic pattern that we could potentially identify.

    “In our theory clusters of life form, grow, and overlap like bubbles in a pot of boiling water,” says lead author Henry Lin of the Harvard-Smithsonian Center for Astrophysics (CfA).

    There are two basic ways for life to spread beyond its host star. The first would be via natural processes such as gravitational slingshotting of asteroids or comets. The second would be for intelligent life to deliberately travel outward. The paper does not deal with how panspermia occurs. It simply asks: if it does occur, could we detect it? In principle, the answer is yes.

    The model assumes that seeds from one living planet spread outward in all directions. If a seed reaches a habitable planet orbiting a neighboring star, it can take root. Over time, the result of this process would be a series of life-bearing oases dotting the galactic landscape.

    “Life could spread from host star to host star in a pattern similar to the outbreak of an epidemic. In a sense, the Milky Way galaxy would become infected with pockets of life,” explains CfA co-author Avi Loeb.

    If we detect signs of life in the atmospheres of alien worlds, the next step will be to look for a pattern. For example, in an ideal case where the Earth is on the edge of a “bubble” of life, all the nearby life-hosting worlds we find will be in one half of the sky, while the other half will be barren.

    Lin and Loeb caution that a pattern will only be discernible if life spreads somewhat rapidly. Since stars in the Milky Way drift relative to each other, stars that are neighbors now won’t be neighbors in a few million years. In other words, stellar drift would smear out the bubbles.

    This research has been accepted for publication in The Astrophysical Journal Letters.

    See the full article here.

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    About CfA

    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy. The long relationship between the two organizations, which began when the SAO moved its headquarters to Cambridge in 1955, was formalized by the establishment of a joint center in 1973. The CfA’s history of accomplishments in astronomy and astrophysics is reflected in a wide range of awards and prizes received by individual CfA scientists.

    Today, some 300 Smithsonian and Harvard scientists cooperate in broad programs of astrophysical research supported by Federal appropriations and University funds as well as contracts and grants from government agencies. These scientific investigations, touching on almost all major topics in astronomy, are organized into the following divisions, scientific departments and service groups.

     
  • richardmitnick 3:04 pm on August 27, 2015 Permalink | Reply
    Tags: Astronomy, ,   

    From U Texas McDonald Observatory: “Dying Stars Suffer from ‘Irregular Heartbeats'” 

    McDonald Observatory bloc

    McDonald Observatory

    26 August 2015

    1
    White Dwarf Outburst

    2
    Keaton Bell

    Some dying stars suffer from ‘irregular heartbeats,’ research led by astronomers at The University of Texas at Austin and the University of Warwick has discovered.

    The team discovered rapid brightening events — outbursts — in two otherwise normal pulsating white dwarf stars. Ninety-seven percent of all stars, including the Sun, will end their lives as extremely dense white dwarfs after they exhaust their nuclear fuel. Such outbursts have never been seen in this type of star before.

    “It’s the discovery of an entirely new phenomenon,” said graduate student Keaton Bell of The University of Texas at Austin. Bell reported the first pulsating white dwarf to show these outbursts, KIC 4552982, in a recent issue of The Astrophysical Journal.

    This week, a team led by recent University of Texas PhD J.J. Hermes, now of the University of Warwick, is reporting the second white dwarf to show this trait: PG1149+057. Hermes’ team includes Bell and others from The University of Texas. Their research is published in the current Astrophysical Journal Letters.

    Both white dwarf discoveries were made using data from the Kepler space mission.

    NASA Kepler Telescope
    Kepler

    The Kepler spacecraft trails Earth in its orbit around the Sun, recording time lapse movies of a few patches of sky for months on end.

    The Kepler data show that in addition to the regular rhythm of pulsations expected from a white dwarf, which cause the star to get a few percent brighter and fainter every few minutes, both stars also experienced arrhythmic, massive outbursts every few days, breaking their regular pulse and significantly heating up their surfaces for many hours.

    “We have essentially found rogue waves in a pulsating star, akin to ‘irregular heartbeats,’” Hermes explained. “These were truly a surprise to see: We have been watching pulsating white dwarfs for more than 50 years now from the ground, and only by being able to stare uninterrupted for months from space have we been able to catch these events.”

    Bell elaborated: “When we build a telescope that observes the sky in an entirely new way, we’re going to end up discovering things that we never expected.” Though Kepler’s notoriety derives from its prowess as a planet hunter, “it’s told us at least as much about stars as it has about planets,” Bell said.

    White dwarfs have been known to pulsate for decades, and some are exceptional clocks, with pulsations that have kept nearly perfect time for more than 40 years. Pulsations are believed to be a naturally occurring stage when a white dwarf reaches the right temperature to generate a mix of partially ionized hydrogen atoms at its surface.

    That mix of excited atoms can store up and then release energy, causing the star to resonate with pulsations characteristically every few minutes. Astronomers can use the regular periods of these pulsations just like seismologists use earthquakes on Earth, to see below the surface of the star into its exotic interior. This was why astronomers targeted these stars with Kepler, hoping to learn more about their dense cores. In the process, they caught these unexpected outbursts.

    “These are highly energetic events, which can raise the star’s overall brightness by more than 15% and its overall temperature by more than 750 degrees in a matter of an hour,” Hermes said. “For context, the Sun will only increase in overall brightness by about 1% over the next 100 million years.”

    There is a narrow range of surface temperatures where pulsations can be excited in white dwarfs, and so far irregularities have only been seen in the coolest of those that pulsate. Thus, these irregular outbursts may not be just an oddity; they have the potential to change the way astronomers understand how pulsations, the regular heartbeats, ultimately cease in white dwarfs.

    “The theory of stellar pulsations has long failed to explain why pulsations in white dwarfs stop at the temperature we observe them to,” Texas’ Keaton Bell said. “That both stars exhibiting this new outburst phenomenon are right at the temperature where pulsations shut down suggests that the outbursts could be the key to revealing the missing physics in our pulsation theory.”

    Astronomers are still trying to settle on an explanation for these outbursts. Given the similarity between the first two stars to show this behavior, they suspect it might have to do with how the pulsation waves interact with themselves, perhaps via a resonance.

    “Ultimately, this may be a new type of nonlinear behavior that is triggered when the amplitude of a pulsation passes a certain threshold, perhaps similar to rogue waves on the open seas here on Earth, which are massive, spontaneous waves that can be many times larger than average surface waves,” Hermes said. “Still, this is a fresh discovery from observations, and there may be more to these irregular stellar heartbeats than we can imagine yet.”

    See the full article here.

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    McDonald Observatory Campus

    Telescopes Are Windows To the Universe

    Astronomers use them to study everything from the asteroids and planets in our own solar system to galaxies billions of light-years away in space and time. Though they bring the mysteries of the universe to us, their workings are anything but mysterious. They gather and focus light from objects in the sky, so that it can be directed into an instrument attached to the telescope, and ultimately, studied in detail by a scientist. At McDonald Observatory, we have several telescopes, built at various times since the Observatory’s founding in the 1930s.

    Here is an introduction to the telescopes that McDonald Observatory astronomers use for their research:

    McDonald Observatory Hobby-Eberly Telescope
    Hobby-Eberly Telescope

    McDonald Observatory Harlan J Smith Telescope
    Harlan J. Smith Telescope

    McDonald Observatory Otto Struve telescope
    Otto Struve Telescope

    McDonald Observatory .8 meter telescope
    0.8-meter Telescope

    McDonald Observatory .9 meter telescope
    0.9-meter Telescope

    McDonald Observatory Rebecca Gale  Telescope Park
    Rebecca Gale Telescope Park

     
  • richardmitnick 1:29 pm on August 27, 2015 Permalink | Reply
    Tags: Astronomy, ,   

    From Hubble: “Hubble Finds That the Nearest Quasar Is Powered by a Double Black Hole” 

    NASA Hubble Telescope

    Hubble

    August 27, 2015

    Ray Villard
    Space Telescope Science Institute, Baltimore, Md.
    410-338-4514
    villard@stsci.edu

    Jana Smith
    University of Oklahoma, Norman, Ok.
    405-325-1701
    jana.smith@ou.edu

    Xinyu Dai
    University of Oklahoma, Norman, Ok.
    405-325-3961
    xdai@ou.edu

    1
    Quasar Host Galaxy Markarian 231
    This Hubble Space Telescope image reveals a bright starlike glow in the center of the interacting galaxy Markarian 231, the nearest quasar to Earth. Located 581 million light-years away, we are seeing the galaxy as it looked before multicelled life first appeared on Earth. Quasars are powered by a central black hole that heats the gas around it to unleash tremendous amounts of energy. Hubble spectroscopic observations infer the presence of two supermassive black holes whirling around each other. Because such a dynamic duo is found in the nearest quasar, it would imply that many quasars host binary-black-hole systems. It would be a natural result of a galaxy merger.
    Object Names: Markarian 231, Mrk 231, UGC 8058, VII Zw 490, QSO B1254+571
    Image Type: Astronomical
    Credit: NASA, ESA, the Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)
    The galaxy pair was imaged with the ACS/WFC instrument with filters F435W (B) and F814W (I) on May 10, 2002.

    NASA Hubble ACS
    ACS

    NASA Hubble WFC3
    WFC

    Astronomers using NASA’s Hubble Space Telescope have found that Markarian 231 (Mrk 231), the nearest galaxy to Earth that hosts a quasar, is powered by two central black holes furiously whirling about each other.

    The finding suggests that quasars — the brilliant cores of active galaxies — may commonly host two central supermassive black holes that fall into orbit about one another as a result of the merger between two galaxies. Like a pair of whirling skaters, the black-hole duo generates tremendous amounts of energy that makes the core of the host galaxy outshine the glow of the galaxy’s population of billions of stars, which scientists then identify as quasars.

    Scientists looked at Hubble archival observations of ultraviolet radiation emitted from the center of Mrk 231 to discover what they describe as “extreme and surprising properties.”

    If only one black hole were present in the center of the quasar, the whole accretion disk made of surrounding hot gas would glow in ultraviolet rays. Instead, the ultraviolet glow of the dusty disk abruptly drops off towards the center. This provides observational evidence that the disk has a big donut hole encircling the central black hole. The best explanation for the observational data, based on dynamical models, is that the center of the disk is carved out by the action of two black holes orbiting each other. The second, smaller black hole orbits in the inner edge of the accretion disk, and has its own mini-disk with an ultraviolet glow.

    “We are extremely excited about this finding because it not only shows the existence of a close binary black hole in Mrk 231, but also paves a new way to systematically search binary black holes via the nature of their ultraviolet light emission,” said Youjun Lu of the National Astronomical Observatories of China, Chinese Academy of Sciences.

    “The structure of our universe, such as those giant galaxies and clusters of galaxies, grows by merging smaller systems into larger ones, and binary black holes are natural consequences of these mergers of galaxies,” added co-investigator Xinyu Dai of the University of Oklahoma.

    The central black hole is estimated to be 150 million times the mass of our sun, and the companion weighs in at 4 million solar masses. The dynamic duo completes an orbit around each other every 1.2 years.

    The lower-mass black hole is the remnant of a smaller galaxy that merged with Mrk 231. Evidence of a recent merger comes from the host galaxy’s asymmetry, and the long tidal tails of young blue stars.

    The result of the merger has been to make Mrk 231 an energetic starburst galaxy with a star-formation rate 100 times greater than that of our Milky Way galaxy. The infalling gas fuels the black hole “engine,” triggering outflows and gas turbulence that incites a firestorm of star birth.

    The binary black holes are predicted to spiral together and collide within a few hundred thousand years.

    Mrk 231 is located 581 million light-years away.

    The results were published in the August 14, 2015, edition of The Astrophysical Journal.

    See the full article here.

    Please help promote STEM in your local schools.

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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.

    ESA50 Logo large

    AURA Icon

     
  • richardmitnick 6:06 pm on August 26, 2015 Permalink | Reply
    Tags: Astronomy, ,   

    From NAOJ Subaru: “Dark Matter Map Begins to Reveal the Universe’s Early History” 

    NAOJ

    NAOJ

    July 1, 2015

    Researchers from the National Astronomical Observatory of Japan (NAOJ), Kavli Institute for the Physics and Mathematics of the Universe (Kavli IPMU), the University of Tokyo and other institutions have begun a wide-area survey of the distribution of dark matter in the universe using Hyper Suprime-Cam, a new wide-field camera installed on the Subaru Telescope in Hawai’i. Initial results from observations covering an area of 2.3 square degrees on the sky toward the constellation Cancer revealed nine large concentrations of dark matter, each the mass of a galaxy cluster (Movie, Figure 1). Surveying how dark matter is distributed and how the distribution changes over time is essential to understanding the role of dark energy that controls the expansion of the universe. These first results demonstrate that astronomers now have the techniques and tools to understand dark energy. The next step is for the research team to expand the survey to cover a thousand square degrees on the sky, and thereby unravel the mystery of dark energy and the expansion of the universe.


    Download video here.
    Movie: Numerous galaxies from Subaru Telescope’s Hyper Suprime-Cam, and a map of dark matter determined by weak lensing analysis. The video is downloadable here (File size approx. 160 MB).(Credit: NAOJ/HSC Project)

    2
    Figure 1: A 14 arc minute by 9.5 arc minute section of a Hyper Suprime-Cam image, with contour lines showing the dark matter distribution. A higher resolution images is available by clicking the image. An image with just the background galaxies is available here. There is also a scalable image available in color and black and white. (Credit: NAOJ/HSC Project)

    Mapping dark matter over a wide region is key to understanding the properties of dark energy, which controls the expansion of the universe. These early results demonstrate that with current research techniques and Hyper Suprime-Cam, the team is now ready to explore how the distribution of dark matter in the universe has changed over time, unravel the mystery of dark energy, and explore the universeʻs expansion history with great detail.

    Hyper Suprime-Cam lead developer, Dr. Satoshi Miyazaki, from the National Astronomical Observatory of Japan’s Advanced Technology Center and leader of the research team, praised the ability of the HSC for this work. “Now we know we have the both a technique and a tool for understanding dark energy. We are ready to use Hyper Suprime-Cam to create a 1000 square degree dark matter map that will reveal the expansion history of the universe with precise detail.”

    Using Weak Lensing by Dark Matter to Study Dark Energyʻs Effects

    Ever since 1929, when astronomer Edwin Hubble discovered that the universe is expanding, astronomers used a working model that had the rate of expansion slowing down over time. Gravitational attraction, until recently the only known force acting between galaxies, works against expansion. However, in the 1990s, studies of distant supernovae showed that the universe is expanding faster today than it was in the past. This discovery required a dramatic shift in our understanding of physics: either there is some kind of “dark energy” with a repulsive force that forces galaxies apart, or the physics of gravity needs some fundamental revision (Note 1).

    To unravel the mystery of the universe’s accelerating expansion, it is helpful to look at the relationship between the rate expansion of the universe and the rate at which astronomical objects form. For example, if the universe is expanding quickly, it will take longer for matter to coalesce and form galaxies. Conversely, if the universe is expanding slowly, it is easier for structures like galaxies to form. In effect, there is a direct link between the history of structure formation in the universe, and the history of the universe’s expansion. The challenge in confirming the existence of dark matter and its effect on expansion is that most of the matter in the universe is dark and does not emit light. It cannot be detected directly by telescopes, which are light-collecting machines.

    One technique that can overcome this challenge is the detection and analysis of “weak lensing“. A concentration of dark matter acts as a lens that bends light coming from even more distant objects. By analyzing how that background light is bent and how the lensing distorts the shapes of the background objects, it is possible to determine how dark matter is distributed in the foreground. This analysis of dark matter and its effects lets astronomers determine how it has assembled over time. The assembly history of dark matter can be related to the expansion history of the universe, and should reveal some of the physical properties of dark energy, its strength and how it has changed over time.

    To get a sufficient amount of data, astronomers need to observe galaxies more than a billion light-years away, across an area greater than a thousand square degrees (about one fortieth of the entire sky). The combination of the Subaru telescope, with its 8.2-meter diameter aperture, and Suprime-Cam, Hyper Suprime-Cam’s predecessor, with a field of view of a tenth of a square degree (comparable to the size of the full moon), has been one of the most successful tools in the search of faint distant objects over a wide area of sky.

    However, even for this powerful combo, surveying a thousand degrees of sky at the necessary depth is not realistic. “This is why we spent 10 years to develop Hyper Suprime-Cam, a camera with the same of better image quality as Suprime-Cam, but with a field of view over seven times larger,” said Dr. Satoshi Miyazaki.

    Hyper Suprime-Cam was installed on the Subaru Telescope in 2012. Following test observations, it was made available for open use by the astronomy community in March 2014 (Figure 2). A “strategic” observing program, consisting of more than 300 nights of observing over five years is also underway. The camera, with 870 million pixels, delivers images that cover an area of sky as large as nine full moons in a single exposure, with extremely little distortion, at a fine resolution of seven thousandths of a degree (0.5 arc seconds).

    2
    Figure 2: Hyper Suprime-Cam at Subaru telescope’s prime focus. (Credit: NAOJ/HSC Project)

    Researchers from NAOJ, the University of Tokyo, and collaborators analyzed test data from Hyper Suprime-Cam’s commissioning to see how well it could map dark matter using the weak lensing technique. The data from a two-hour exposure covering 2.3 square degrees revealed crisp images of numerous galaxies. By measuring their individual shapes, the team created a map of the dark matter hiding in the foreground. The result was the discovery of nine clumps of dark matter, each weighing as much a galaxy cluster. The reliability of the weak lensing analysis, and the resulting dark matter maps, have been confirmed by observations with other telescopes that show actual galaxy clusters corresponding to the dark matter clumps discovered by Hyper Suprime-Cam. They utilized the archived Deep Lens Survey (PI: Tony Tyson, LSST Chief Scientist) data for the optical cluster identification.

    The number of galaxy clusters found by Hyper Suprime-Cam exceeds predictions from current models of the universe’s early history (Figure 3). As the research team expands the dark matter map to their goal of a thousand square degrees, the data should reveal whether this excess is real or just a statistical fluke. If the excess is real, it suggests that there was not as much dark energy as expected in the past, which allows the universe to expand gently and stars and galaxies to form quickly.

    3
    Figure 3: The data show a clear excess of dark matter concentrations over the current best theoretical model. Right: A schematic showing the dark matter concentrations discovered in the Hyper Suprime-Cam data. Left: A schematic showing predictions from current theoretical models. (Credit: NAOJ/HSC Project)

    Using weak lensing to map dark matter distribution is a way to discover astronomical objects using their mass, to learn that something exists and how much it weighs at the same time. It gives a direct measurement of mass that is typically unavailable when using other methods of discovery (Note 2). Therefore, mass maps of dark matter are an essential tool for understanding the expansion history of the universe precisely and accurately.

    These are the first scientific results from Hyper Suprime-Cam and were accepted for publication in the July 1, 2015 edition of the Astrophysical Journal (Miyazaki et al. 2015, ApJ 807, 22, “Properties of Weak Lensing Clusters Detected on Hyper Suprime-Cam 2.3 Square Degree Field”). The on-line version was posted in June 25, 2015 and is available here or as a preprint. This research has received Grants-in-Aid for Scientific Research (18072003 and 26800093) and World Premier International Research Center Initiative support through the Japanese Society for the Promotion of Science.

    Authors:

    Satoshi Miyazaki: National Astronomical Observatory of Japan; SOKENDAI (The Graduate University for Advanced Studies), Japan
    Masamune Oguri: Department of Physics, Faculty of Science, University of Tokyo/Research Center for the Early Universe, University of Tokyo/Kavli Institute for the Physic and Mathematics of the Universe (Kavli IPMU, WPI), the University of Tokyo, Japan
    Takashi Hamana: National Astronomical Observatory of Japan; SOKENDAI (The Graduate University for Advanced Studies), Japan
    Masayuki Tanaka: National Astronomical Observatory of Japan
    Lance Miller: Department of Physics, Oxford University, United Kingdom
    Yousuke Utsumi: Hiroshima Astrophysical Science Center, Hiroshima University, Japan
    Yutaka Komiyama: National Astronomical Observatory of Japan; SOKENDAI (The Graduate University for Advanced Studies), Japan
    Hisanori Furusawa: National Astronomical Observatory of Japan
    Junya Sakurai: SOKENDAI (The Graduate University for Advanced Studies), Japan/ National Astronomical Observatory of Japan
    Satoshi Kawanomoto: National Astronomical Observatory of Japan
    Fumiaki Nakata: Subaru Telescope, National Astronomical Observatory of Japan, USA
    Fumihiro Uraguchi: Subaru Telescope, National Astronomical Observatory of Japan, USA
    Michitaro Koike: National Astronomical Observatory of Japan
    Daigo Tomono: Subaru Telescope, National Astronomical Observatory of Japan, USA
    Robert Lupton: Department of Astrophysical Sciences, Princeton University, USA
    James E. Gunn: Department of Astrophysical Sciences, Princeton University, USA
    Hiroshi Karoji: National Institutes of Natural Sciences, Japan
    Hiroaki Aihara: Kavli Institute for the Physic and Mathematics of the Universe (Kavli IPMU, WPI), the University of Tokyo, Japan
    Hitoshi Murayama: Kavli Institute for the Physic and Mathematics of the Universe (Kavli IPMU, WPI), the University of Tokyo, Japan
    Masahiro Takada: Kavli Institute for the Physic and Mathematics of the Universe (Kavli IPMU, WPI), the University of Tokyo, Japan

    Notes:

    1. The 2011 Nobel Prize in Physics was awarded “for the discovery of the accelerating expansion of the universe through observations of distant supernovae” with one half going to Saul Perlmutter (Lawrence Berkeley National Lab & the University of California, Berkeley) and the other half going jointly to Brian P. Schmidt (Australian National University) and Adam G. Riess (Johns Hopkins University & Space Science Institute).
    2. Light, electromagnetic radiation of all wavelengths including, radio, visible light, and x-rays, is the standard search tool for astronomical objects. In general, there is no simple relationship between the amount of light an object emits and its mass. The distortion of light observed in weak lensing is a direct measure of mass, and is therefore a much more reliable tool for determining the distribution of mass in the universe.

    See the full article here.

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    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

    NAOJ Subaru Telescope

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    NAOJ Okayama Astrophysical Observatory Telescope
    Okayama Astrophysical Observatory

    The National Astronomical Observatory of Japan (NAOJ) is an astronomical research organisation comprising several facilities in Japan, as well as an observatory in Hawaii. It was established in 1988 as an amalgamation of three existing research organizations – the Tokyo Astronomical Observatory of the University of Tokyo, International Latitude Observatory of Mizusawa, and a part of Research Institute of Atmospherics of Nagoya University.

    In the 2004 reform of national research organizations, NAOJ became a division of the National Institutes of Natural Sciences.

     
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