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  • richardmitnick 2:08 pm on October 23, 2016 Permalink | Reply
    Tags: , ,   

    From Science Alert: “Astrophysicists have witnessed plasma ripples moving along Earth’s bow shock” 


    Science Alert

    20 OCT 2016

    APS/Carin Cain

    These things actually exist.

    Astrophysicists have witnessed tiny ripples forming on Earth’s ‘bow shock’ – the plasma shockwaves produced when solar winds smash into Earth’s magnetic field.

    While the ripples have long been hypothesised, actually finding them in space has proven a challenge. Now, researchers have been able to study them for the first time, and it could help us to finally understand cosmic rays.

    The breakthrough came thanks to thanks to NASA’s Magnetospheric MultiScale satellites (MMS).



    “With the new MMS spacecraft we can, for the first time, resolve the structure of the bow shock at these small scales,” said team leader Andreas Johlander, from the Swedish Institute of Space Physics (IRF).

    So, what are these ripples and where do they come from?

    Much of the visible matter in the Universe is actually plasma, a hot ionised gas. This plasma can produce shockwaves around other objects in space – such as planets, stars, and supernovae – when it interacts with the magnetic fields around them.

    Just imagine it like a wave of water travelling around the bow of a ship, where the water is plasma and the ship’s bow is Earth’s magnetic field (or magnetosphere), sending the plasma rushing to either side as it displaces it.

    These shockwaves are known to act basically like particle accelerators, and shockwaves around supernovae are commonly thought to produce cosmic rays, high energy atoms or particles that travel near the speed of light through space.

    But the thing is, we don’t really understand exactly how the particles in these shockwaves get so fast.

    Based on previously developed mathematical models, researchers think that tiny ripples in these shockwaves might be to blame for this acceleration, though finding and actually witnessing them has been impossible because they are super small and fast, making them hard to spot with traditional technologies.

    That is, until now, because the new team was able to witness these ripples inside Earth’s bow shock.

    To pull off this feat and to analyse these ripples further, the team employed NASA’s MMS – a group of four satellites that fly in a tetrahedral formation around Earth’s magnetosphere to sample plasma activity.

    This represents the first time researchers have been able to successfully witness these ripples, providing proof – once and for all – of their existence other than in mathematical calculations.

    But it’s just the first step – now we have to figure out how they work.

    With further study, the team says that understanding how these ripples in plasma shocks help accelerate and heat particles might shine new light on how cosmic rays form around supernovae.

    “These direct observations of shock ripples in a space plasma allow us to characterise the physical properties of the ripples. This brings us one step closer to understanding how shocks can produce cosmic rays,” said Johlander.

    The team’s work was published in Physical Review Letters.

    See the full article here .

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  • richardmitnick 10:02 am on October 23, 2016 Permalink | Reply
    Tags: , , , NASA’s MAVEN Mission Observes Ups and Downs of Water Escape from Mars   

    From “NASA’s MAVEN Mission Observes Ups and Downs of Water Escape from Mars” 

    Astrobiology Magazine

    Astrobiology Magazine

    Oct 22, 2016
    No writer credit found


    After investigating the upper atmosphere of the Red Planet for a full Martian year, NASA’s MAVEN mission has determined that the escaping water does not always go gently into space.

    Sophisticated measurements made by a suite of instruments on the Mars Atmosphere and Volatile Evolution, or MAVEN, spacecraft revealed the ups and downs of hydrogen escape – and therefore water loss. The escape rate peaked when Mars was at its closest point to the sun and dropped off when the planet was farthest from the sun. The rate of loss varied dramatically overall, with 10 times more hydrogen escaping at the maximum.

    “MAVEN is giving us unprecedented detail about hydrogen escape from the upper atmosphere of Mars, and this is crucial for helping us figure out the total amount of water lost over billions of years,” said Ali Rahmati, a MAVEN team member at the University of California at Berkeley who analyzed data from two of the spacecraft’s instruments.

    Hydrogen in Mars’ upper atmosphere comes from water vapor in the lower atmosphere. An atmospheric water molecule can be broken apart by sunlight, releasing the two hydrogen atoms from the oxygen atom that they had been bound to. Several processes at work in Mars’ upper atmosphere may then act on the hydrogen, leading to its escape.

    This loss had long been assumed to be more-or-less constant, like a slow leak in a tire. But previous observations made using NASA’s Hubble Space Telescope and ESA’s Mars Express orbiter found unexpected fluctuations. Only a handful of these measurements have been made so far, and most were essentially snapshots, taken months or years apart. MAVEN has been tracking the hydrogen escape without interruption over the course of a Martian year, which lasts nearly two Earth years.

    This image shows atomic hydrogen scattering sunlight in the upper atmosphere of Mars, as seen by the Imaging Ultraviolet Spectrograph on NASA’s Mars Atmosphere and Volatile Evolution mission. About 400,000 observations, taken over the course of four days shortly after the spacecraft entered orbit around Mars, were used to create the image. Hydrogen is produced by the breakdown of water, which was once abundant on Mars’ surface. Because hydrogen has low atomic mass and is weakly bound by gravity, it extends far from the planet (the darkened circle) and can readily escape. Credits: NASA/Goddard/University of Colorado

    “Now that we know such large changes occur, we think of hydrogen escape from Mars less as a slow and steady leak and more as an episodic flow – rising and falling with season and perhaps punctuated by strong bursts,” said Michael Chaffin, a scientist at the University of Colorado at Boulder who is on the Imaging Ultraviolet Spectrograph (IUVS) team. Chaffin is presenting some IUVS results on Oct. 19 at the joint meeting of the Division for Planetary Sciences and the European Planetary Science Congress in Pasadena, California.

    In the most detailed observations of hydrogen loss to date, four of MAVEN’s instruments detected the factor-of-10 change in the rate of escape. Changes in the density of hydrogen in the upper atmosphere were inferred from the flux of hydrogen ions – electrically charged hydrogen atoms – measured by the Solar Wind Ion Analyzer and by the Suprathermal and Thermal Ion Composition instrument. IUVS observed a drop in the amount of sunlight scattered by hydrogen in the upper atmosphere. MAVEN’s magnetometer found a decrease in the occurrence of electromagnetic waves excited by hydrogen ions, indicating a decrease in the amount of hydrogen present.

    By investigating hydrogen escape in multiple ways, the MAVEN team will be able to work out which factors drive the escape. Scientists already know that Mars’ elliptical orbit causes the intensity of the sunlight reaching Mars to vary by 40 percent during a Martian year. There also is a seasonal effect that controls how much water vapor is present in the lower atmosphere, as well as variations in how much water makes it into the upper atmosphere. The 11-year cycle of the sun’s activity is another likely factor.

    “In addition, when Mars is closest to the sun, the atmosphere becomes turbulent, resulting in global dust storms and other activity. This could allow the water in the lower atmosphere to rise to very high altitudes, providing an intermittent source of hydrogen that can then escape,” said John Clarke, a Boston University scientist on the IUVS team. Clarke will present IUVS measurements of hydrogen and deuterium – a form of hydrogen that contains a neutron and is heavier – on Oct. 19 at the planetary conference.

    By making observations for a second Mars year and during different parts of the solar cycle, the scientists will be better able to distinguish among these effects. MAVEN is continuing these observations in its extended mission, which has been approved until at least September 2018.

    “MAVEN’s findings reveal what is happening in Mars’ atmosphere now, but over time this type of loss contributed to the global change from a wetter environment to the dry planet we see today,” said Rahmati.

    See the full article here .

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  • richardmitnick 9:51 am on October 23, 2016 Permalink | Reply
    Tags: , , , , OA-5 Cygnus, Orbital ATK   

    From NASA SpaceFlight: “OA-5 Cygnus completes journey to the ISS” 

    NASA Spaceflight

    NASA Spaceflight


    Orbital ATK’s latest Cygnus resupply ship completed rendezvous and capture operations with the International Space Station (ISS) on Sunday morning. The OA-5 Cygnus – packed with equipment and supplies for the crew of the orbital outpost – had to wait her turn to arrive, allowing for the docking of the Soyuz MS-02 spacecraft on Friday.

    Cygnus OA-5 Arrival:

    he latest Cygnus arrival is a significant milestone for the resupply needs of the ISS, having launched on the first upgraded Antares rocket.

    The requirement to upgrade the Antares with new engines was due to the loss of the CRS-3 mission, which failed just seconds after lift-off from the Wallops launch site two years ago.


    Two interim missions – OA-4 and OA-6 – were successfully launched on United Launch Alliance (ULA) Atlas V rockets, flying out of Cape Canaveral Air Force Station SLC-41 in Florida in December 2015 and March 2016, respectively.

    For those missions, the extended Cygnus spacecraft was pushed uphill by the Centaur upper stage. This was also the debut of the larger capacity cargo craft.

    During the March mission, the Centaur came to the aid of Cygnus’ orbital requirements, following a shortfall in the Atlas V booster’s performance.

    With Antares making her comeback from the CRS-3 failure, the OA-5 mission marked the first time this larger Cygnus will enjoy a push from Orbital ATK’s beefy upper stage.


    Both the new Antares 230 configuration and the Castor 30XL upper stage performed without issue, allowing Cygnus to begin her pursuit of the ISS.

    However, due to the timing of the mission, Cygnus had to “loiter” on orbit, waiting for the docking of Soyuz MS-02 – containing the precious cargo of three new station occupants – which was completed on Friday.

    While patiently waiting her turn, Orbital ATK mission controllers in Dulles, Virginia, spent the early days of Cygnus’ mission uploading and executing the first of a series of rendezvous phasing burns (called DV – Delta Velocity burns) to refine the spacecraft’s trajectory toward the Station.

    The first DV burn was conducted in the early phasing period. Lasting approximately 10 minutes, this was designed to raise Cygnus from its initial near-circular 230km orbit to the 400km orbit of the ISS.

    A similarly long DV burn followed, again to raise Cygnus to its proper orbital altitude.

    This was then followed by a planned phasing burn to align Cygnus into the exact orbital corridor of the Station. A final set of DV burns – conducted over the weekend – brought Cygnus to its “Go/No-Go for Joint-Ops” decision point, which it reached roughly five hours prior to capture.

    Once Cygnus received the “go” from MCC-H (Mission Control Center – Houston) for Joint Ops, Cygnus slowly approached the Station to the Joint Targeting Reference Point (JTRP), which it arrived at just over three hours prior to capture.


    From this point until capture and berthing, every step of the rendezvous required a strong communications link through the JEM (Japanese Experiment Module) PROX system between Cygnus, the ISS, and ground controllers.

    This communication structure ensured the ability to manually abort – or at least retreat – Cygnus’ approach to the Station in the event of a problem with the spacecraft or the ISS.

    Once at the JTRP, Cygnus stopped relative motion with the ISS and awaited a second Go/No-Go decision from MCC-H.

    At this point, Cygnus was in the Joint Operations Phase (JOPS) of approach, as overviewed in documentation acquired by L2.

    Approximately three hours before capture, and with MCC-H providing a “go” to proceed, Cygnus performed the first of four ADV thruster burns (ADV1) to begin moving closer to Station.


    During these proximity ADV burns, Cygnus – until capture – made use of the TriDAR vision system designed by Canadian company Neptec with the support of NASA and the Canadian Space Agency.

    TriDAR – tested during several Space Shuttle missions – provides Cygnus controllers with real-time visual guidance for navigation, rendezvous and docking procedures.

    After Cygnus’ completed her first two ADV burns, the ISS maneuvered to capture attitude – a 5 minute process that took place just over two hours prior to targeted capture time.

    Then, MCC-H issued another Go/No-Go decision regarding two more ADV burns for Cygnus, which took the spacecraft to its 250m hold point below the ISS.


    MCC-H then gave the “go” for Cygnus to depart the 250m hold point and enter the Keep Out Sphere (KOS) of the ISS.

    Cygnus pulsed its thrusters and enter the KOS.

    Up until this point, Orbital ATK controllers at their facility in Dulles had full control over Cygnus.

    Once Cygnus entered the KOS, NASA controllers at MCC-H joined the Orbital ATK team for the tricky rendezvous and berthing of Cygnus.

    Just under half an hour prior to capture, Cygnus arrived at the 30m Hold Point.


    Five minutes later, Cygnus received the “go” to proceed to the capture point, at which time it departed the 30m Hold Point just over 15 minutes prior to capture.

    Cygnus then arrived at its capture point 12m from the ISS 8 minutes prior to the first capture attempt Expedition 49 astronauts Kate Rubins of NASA and Takuya Onishi of the Japan Aerospace Exploration Agency using the space station’s robotic arm to grapple Cygnus.

    Using the Station’s 17.5m Space Station Remote Manipulator System (SSRMS) robotic arm to grab hold of Cygnus, the capture was completed at approximately 07:28 EDT.

    After Cygnus was firmly in the SSRMS’s grip, robotic operations will maneuver the craft to Node-1 Unity (delivered by Space Shuttle Endeavour during the first ISS construction mission in December 1998) where the craft will be berthed at the ISS.

    Either later on Sunday or early on Monday, the crew will start to unpack than 5,100 pounds of science and research in support of dozens of research investigations, as well as crew supplies and hardware.


    This mission involves the seventh Cygnus spacecraft, designated CRS Orbital ATK 5 (OA-5).

    Orbital name their Cygnus spacecraft after astronauts, with OA-5 being named the SS Alan Poindexter.

    Born in November 1961, Poindexter served in the US Navy including as an F-14 pilot in the First Gulf War and later as a test pilot, before joining NASA in 1998.

    He flew aboard two Space Shuttle missions; the first as pilot of Atlantis during the STS-122 mission that delivered the Columbus module to the International Space Station in February 2008.

    Cygnus will remain at the space station until November 18, when the spacecraft will be used to dispose of several tons of trash during its fiery reentry into Earth’s atmosphere, and conduct the spacecraft fire experiment.

    (Images: Orbital ATK, NASA and L2 including renders from L2 artist Nathan Koga – The full gallery of Nathan’s (SpaceX Dragon to ITS, SLS, Commercial Crew and more) L2 images can be *found here*)

    (To join L2, click here:

    See the full article here .

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    Stem Education Coalition, 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, 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 4:11 pm on October 22, 2016 Permalink | Reply
    Tags: , , , Idunn Mons volcano,   

    From DLR: “Recently active lava flows on the eastern flank of Idunn Mons on Venus” 

    DLR Bloc

    German Aerospace Center

    18 October 2016

    Manuela Braun
    German Aerospace Center (DLR)
    Corporate Communications, Editor, Human Space Flight, Space Science, Engineering
    Tel.: +49 2203 601-3882
    Fax: +49 2203 601-3249

    Dr. Jörn Helbert
    Deutsches Zentrum für Luft- und Raumfahrt (DLR) – German Aerospace Center
    Tel.: +49 30 67055-319
    Fax: +49 30 67055-384

    Elevation model of Idunn Mons
    Area characterized by recent volvanic activity
    Five lava flow units identified during mapping process

    The European Space Agency’s (ESA) Venus Express mission has provided a great amount of data from the surface and atmosphere of Earth’s inner twin planet.

    ESA/Venus Express
    ESA/Venus Express

    Among these observations was the mapping of the southern hemisphere of Venus in the near infrared spectral range using the VIRTIS (Visible and InfraRed Thermal Imaging Spectrometer) instrument. However, the thick and permanent cloud cover of Venus limits the achievable resolution, similar to observing a scene through fog. Using a numerical model, planetary researchers at the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) pushed the limits of the data resolution. With this new technique, the emissivity anomalies were analysed on the top and eastern flank of Idunn Mons, a volcano with a diameter of 200 kilometres at its base situated in the southern hemisphere of Venus. These anomalies provide an indication of geologically recent volcanism in this area. “We could identify and map distinctive lava flows from the top and eastern flank of the volcano, which might have been recently active in terms of geologic time,” says Piero D’Incecco, the DLR planetary researcher who presented these results at the joint 48th meeting of the American Astronomical Society’s Division for Planetary Sciences (DPS) and 11th European Planetary Science Congress in Pasadena, California.

    “With our new technique we could combine the infrared data with much higher-resolution radar images from the NASA Magellan mission, having been in orbit about Venus from 1990 until 1992.


    It is the first time that – combining the datasets from two different missions – we can perform a high resolution geologic mapping of a recently active volcanic structure from the surface of a planet other than Earth.” This study will also provide motivation for future projects focused on the exploration of Venus, as for example the NASA Discovery VERITAS mission proposal or the ESA EnVision M5 mission proposal that – in combining high-resolution radar and near-infrared mapping – will extend the frontiers of our current knowledge of the geology of Venus.

    Search for location and extent of the lava flows

    From 2006 until 2014 the ESA Venus Express probe analysed the atmosphere and surface of Earth’s twin planet. VIRTIS has provided data that indicates the occurrence of recent volcanic activity on Venus. DLR scientists Piero D’Incecco, Nils Müller, Jörn Helbert and Mario D’Amore selected the eastern flank of Idunn Mons – Imdr Regio’s single large volcano – as the study area, since it was identified in VIRTIS data as one of the regions with relatively high values of thermal emissivity at one micron wavelength.

    Using the capabilities of specific techniques developed in the Planetary Spectroscopy Laboratory group at DLR in Berlin, the study intends to identify location and extent of the sources of such anomalies, thus the lava flows responsible for the relatively high emissivity observed by VIRTIS over the eastern flank of Idunn Mons. Therefore the lava flow units on the top and eastern flank of Idunn Mons are mapped, varying the values of simulated one micron emissivity assigned to the mapped units. For each configuration, the total mismatch as root mean square error in comparison with the VIRTIS observations is calculated. In the best-fit configuration, the flank lava flows are characterised by high values of one micron simulated emissivity. Hence, the lava flow units on the eastern flank on Idunn Mons are likely responsible for the relatively high one micron emissivity anomalies observed by VIRTIS. This result is supported by the reconstructed post-eruption stratigraphy, displaying the relative dating of the mapped lava flows, that is independent of the 1 micron emissivity modelling. Values of average microwave emissivity extracted from the lava flow units range around the global mean, which is consistent with dry basalts.

    See the full article here .

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    DLR Center

    DLR is the national aeronautics and space research centre of the Federal Republic of Germany. Its extensive research and development work in aeronautics, space, energy, transport and security is integrated into national and international cooperative ventures. In addition to its own research, as Germany’s space agency, DLR has been given responsibility by the federal government for the planning and implementation of the German space programme. DLR is also the umbrella organisation for the nation’s largest project management agency.

    DLR has approximately 8000 employees at 16 locations in Germany: Cologne (headquarters), Augsburg, Berlin, Bonn, Braunschweig, Bremen, Goettingen, Hamburg, Juelich, Lampoldshausen, Neustrelitz, Oberpfaffenhofen, Stade, Stuttgart, Trauen, and Weilheim. DLR also has offices in Brussels, Paris, Tokyo and Washington D.C.

  • richardmitnick 10:59 am on October 22, 2016 Permalink | Reply
    Tags: , , Io's volcanism,   

    From Keck: “Long-Term, Hi-Res Tracking of Eruptions on Jupiter’s Moon Io” 

    Keck Observatory

    Keck Observatory.
    Keck, with Subaru and IRTF (NASA Infrared Telescope Facility). Vadim Kurland

    Keck Observatory

    October 20, 2016
    Katherine de Kleer

    Imke de Pater

    Bill Brown
    W. M. Keck Observatory
    (808) 881-3514

    All hot spot detections from August 2013 through December 2015 shown on a full map of Io. Each circle represents a new detection; the size of the circle corresponds logarithmically to the intensity, and more opaque regions are where a hot spot was detected multiple times. The color and symbol indicate the type of eruption, following the legend. Loki Patera is at 310 West, 10 North and KurdalagonPatera is at 220 West, 50 South. Credit: Katherine de Kleer and Imke de Pater, UC Berkeley.

    Jupiter’s moon Io continues to be the most volcanically active body in the solar system, as documented by the longest series of frequent, high-resolution observations of the moon’s thermal emission ever obtained.

    Using near-infrared adaptive optics on two of the world’s largest telescopes– the 10-meter Keck II and the 8-meter Gemini North, both located near the summit of the dormant volcano Maunakea in Hawaii – University of California, Berkeley astronomers tracked 48 volcanic hotspots on the surface over a period of 29 months from August 2013 through the end of 2015.

    Gemini/North telescope at Mauna Kea, Hawaii, USA
    Gemini/North telescope at Mauna Kea, Hawaii, USA

    Images of Io at different near-infrared wavelengths; the name of the filter is indicated in the black box at the start of each section. The bright spots are thermal emissions from Io’s myriad volcanoes. Note the increasing number of hot spots detected at longer wavelengths, i.e. towards the bottom of the figure. Credit: Katherine de Kleer and Imke de Pater, UC Berkeley

    Without adaptive optics – a technique that removes the atmospheric blur to sharpen the image – Io is merely a fuzzy ball. Adaptive optics can separate features just a few hundred kilometers apart on Io’s 3,600-kilometer-diameter surface.

    “On a given night, we may see half a dozen or more different hot spots,” said Katherine de Kleer, a UC Berkeley graduate student who led the observations. “Of Io’s hundreds of active volcanoes, we have been able to track the 50 that were the most powerful over the past few years.”

    She and Imke de Pater, a UC Berkeley professor of astronomy and of earth and planetary science, observed the heat coming off of active eruptions as well as cooling lava flows and were able to determine the temperature and total power output of individual volcanic eruptions.They tracked their evolution over days, weeks and sometimes even years.

    Interestingly, some of the eruptions appeared to progress across the surface over time, as if one triggered another 500 kilometers away.

    “While it stretches the imagination to devise a mechanism that could operate over distances of 500 kilometers, Io’s volcanism is far more extreme than anything we have on Earth and continues to amaze and baffle us,” de Kleer said.

    De Kleer and de Pater will discuss their observations at a media briefing on Oct. 20 during a joint meeting of the American Astronomical Society’s Division for Planetary Sciences and the European Planetary Science Congress in Pasadena, California. Papers describing the observations have been accepted for future publication by the journal Icarus.

    Tidal heating

    Io’s intense volcanic activity is powered by tidal heating — heating from friction generated in Io’s interior as Jupiter’s intense gravitational pull changes by small amounts alongIo’s orbit. Models for how this heating occurs predict that most of Io’s total volcanic power should be emitted either near the poles or near the equator, depending on the model, and that the pattern should be symmetric between the forward- and backward-facing hemispheres in Io’s orbit (that is, at longitudes 0-180 degrees versus 180-360 degrees).

    That’s not what they saw. Over the observational period, August 2013 through December 2015, the team obtained images of Io on 100 nights. Though they saw a surprising number of short-lived but intense eruptions that appeared suddenly and subsided in a matter of days, every single one took place on the trailing face of Io (180-360 degrees longitude) rather than the leading face, and at higher latitudes than more typical eruptions.

    “The distribution of the eruptions is a poor match to the model predictions,” de Kleer said, “but future observations will tell us whether this is just because the sample size is too small, or because the models are too simplified. Or perhaps we’ll learn that local geological factors play a much greater role in determining where and when the volcanoes erupt than the physics of tidal heating do.”

    One key target of interest was Io’s most powerful persistent volcano, Loki Patera, which brightens by more than a factor of 10 every 1-2 years. A patera is an irregular crater, usually volcanic.

    Many scientists believe that Loki Patera is a massive lava lake, and that these bright episodes represent its overturning crust, like that seen in lava lakes on Earth. In fact, the heat emissions from Loki Patera appear to travel around the lake during each event, as if from a wave moving around a lake triggering the destabilization and sinking of portions of crust. Prior to 2002, this front seemed to travel around the cool island in the center of the lake in a counter-clockwise direction.

    After an apparent cessation of brightening events after 2002, de Pater observed renewed activity in 2009.

    “With the renewed activity, the waves traveled clockwise around the lava lake,” she noted.

    Another volcano, Kurdalagon Patera, produced unusually hot eruptions twice in the spring of 2015, coinciding with the brightening ofan extended cloud of neutral material that orbits Jupiter.This provides circumstantial evidence that eruptions on the surface are the source of variability in this neutral cloud, though it’s unclear why other eruptions were not also associated with brightening, de Kleer said.

    De Kleer noted that the Keck and Gemini telescopes, both atop the dormant volcano Maunakea, complement one another. Gemini North’s queue scheduling allowed more frequent observations – often several a week – while Keck’s instruments are sensitive also to longer wavelengths (5 microns), showing cooler features such as older lava flows that are invisible in the Gemini observations.

    The astronomers are continuing their frequent observations of Io, providing a long-term database of high spatial resolution images that not even Galileo, which orbited Jupiter for eight years, was able to achieve.

    The work is supported by a grant from the National Science Foundation (AST-1313485)and de Kleer’s NSF Graduate Research Fellowship(DGE-1106400).

    Link to science paper.
    Link to science paper.

    See the full article here .

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

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

    Today Keck Observatory is supported by both public funding sources and private philanthropy. As a 501(c)3, the organization is managed by the California Association for Research in Astronomy (CARA), whose Board of Directors includes representatives from the California Institute of Technology and the University of California, with liaisons to the board from NASA and the Keck Foundation.
    Keck UCal

    Keck NASA

    Keck Caltech

  • richardmitnick 10:52 am on October 22, 2016 Permalink | Reply
    Tags: Are ‘dark comets’ the Universe’s biggest threat to Earth?, , , ,   

    From Ethan Siegel: “Are ‘dark comets’ the Universe’s biggest threat to Earth?” 

    Ethan Siegel

    A comet or asteroid that struck Earth because it wasn’t detected quickly enough is one of humanity’s greatest natural threats. Image credit: NASA / Don Davis.

    Might Armageddon come not from an asteroid or a comet, but by something completely unseen altogether?

    “Honestly, if you’re given the choice between Armageddon or tea, you don’t say ‘what kind of tea?” -Neil Gaiman

    There are many cosmic catastrophes that could do us in, completely irrespective of anything that happens here on Earth. A star could pass into our Solar System and swallow up our planet whole, or eject us from our orbit and cause us to permanently freeze over. A supernova or gamma ray burst could go off too close to us, disintegrating all life on the Earth’s surface. Or, as we know it did at least once before some 65 million years ago, a large, fast-moving object like a comet or asteroid could have a catastrophic collision with Earth. At least if we’re prepared, we ought to see one coming and be able to take preparations. But what if there’s no chance; what if an incoming comet is somehow unseeable? David Bertone heard about that possibility, and wants to know!

    “I recently came across a few articles regarding dark comets, and to say the least it freaked me out! […] Is Napier right about the dark comets? Are they truly a threat to us [on] earth?”

    We have lots of threats to life on Earth, and getting struck by a large, fast-moving, unexpected object is certainly among them!

    Comet Lovejoy, as seen from the International Space Station, poses no threat to Earth. Image credit: NASA / ISS.

    Bill Napier is a scientist who studies potentially hazardous objects from outer space. He rightly points out that, while most efforts to catalogue the potential dangers to Earth focus on near-Earth objects like the asteroids that leave the main belt and cross Earth’s orbit, that might not be a good reflection of what’s actually likely to get us. Nor is it necessarily an asteroid orbiting interior to Jupiter or a comet orbiting exterior to the orbit of Neptune, just waiting to get perturbed and flung into the inner Solar System. There are plenty of objects orbiting in between the orbits of the four gas giants, known as centaurs, that could be hurtled inwards without any warning, and most of them have not been catalogued. Napier postulates that many of these centaurs may be invisible to us, even after being flung inwards, until it’s far too late.

    While asteroids (grey) and Kuiper Belt objects beyond Neptune (blue and orange) are generally considered Earth’s greatest threats, the centaurs (green) number over 44,000. Image credit: WilyD at English Wikipedia.

    But this brings up an important question: what could render a comet dark, or otherwise unseeable? It isn’t simply going to be a comet that comes towards us from the outer Solar System that’s terrible at reflecting light. Sure, a centaur could have had all its volatile ices boiled off over billions of years, reducing its reflectivity tremendously. As obvious as that seems, the amount of light the Sun emits is so extreme that even a medium-sized comet (or centaur) that absorbed 99.9% of the Sun’s light would still be easily visible at the distance of Saturn. Moreover, comets tend to be made up of mostly ices, which are highly reflective and which get brought to the surface as a comet heats up. The only thoroughly ”dark” bodies in our Solar System are more like our Moon, which still reflects light very brightly, as any casual watcher of the night sky will tell you. An object that was as dark as any naturally occurring, abundant element or compound would still be visible from its reflected sunlight, particularly if you looked in the infrared portion of the spectrum.

    Infrared telescopes can see “dark” objects just as well as they can see bright ones. Image credit: NASA/JPL-Caltech.

    But there are other possibilities to consider. What if an incoming, highly reflective comet were oriented bizarrely? What if it was quite icy, but reflected all the sunlight that struck it away from Earth, like some kind of strange crystal? It’s less obvious, but that wouldn’t work, either. When an object like that entered the planet-containing portion of the Solar System, it would heat up. Heat acting on the ices causes the development of a long tail that points away from the Sun, and this will be easily observable from one of many professional or even amateur all-sky surveys before too much time has passed.

    Comet 67P/C-G as imaged by Rosetta. Image credit: ESA/Rosetta/NAVCAM — CC BY-SA IGO 3.0.

    But perhaps nature will conspire to make that tail unseeable from our point of view? In order for the tail to be hidden, the incoming comet would need to be directed straight at us, aligned so that the Sun, the Earth and the comet made a straight line. If the tail points directly away from us and is hidden behind the comet, that would render everything invisible, and we wouldn’t be able to see it, right? Unfortunately, that’s wrong, too. Comet tails don’t simply point away from the Sun, they spread outwards away from a comet. Even a “head-on” comet like this would have a visible coma around it. Again, amateur or professional astronomers would catch this quickly.

    The coma of comet 17P/Holmes was visible, even when the comet appeared nearly face-on. Image credit: Wikimedia Commons user Gil-Estel under a c.c.-by-2.5 license.

    But there is a real danger of an invisible comet, and it’s very different from the form that Napier envisions in any of his scenario. Imagine, if you will, that a bright, reflective, tail-and-coma-containing comet were headed right for us. Is there any direction it could approach us that you can think of that would render it completely unable to be seen? There is: from the direction of the Sun.

    An X-class solar flare erupted from the Sun’s surface in 2012. Objects like asteroids or comets would be invisible against the brightness of the Sun, and you wouldn’t dare point a telescope in that direction anyway. Image credit: NASA/Solar Dynamics Observatory (SDO) via Getty Images.

    Telescopes don’t dare point too close to the Sun, even from space, since even a glimmer of direct sunlight will ruin and fry your optical system. If any object — comet, asteroid, centaur, even a kicked-up fragment from a collision with Mercury — either approached the Sun from behind it (from our perspective) or were sling-shotted around it, the right trajectory could send it hurtling towards Earth. This is part of the reason why having NASA’s STEREO satellites online is so important.

    Conceptual drawing of NASA’s twin STEREO spacecraft monitoring the Sun. Image credit: NASA.

    At this point, the technology to deflect an incoming asteroid or comet a significant amount in a short amount of time hasn’t been developed, but at least by having a set of observatories at different locations in the Solar System, we could see everything that was headed for us. In the future, more sensitive infrared all-sky surveys will make a far more complete census of the centaurs in our Solar System, and the launch of WFIRST in the 2020s will help us map potentially hazardous objects to much greater distances than we’ve presently done.


    But the odds of a distant object being hurled into us after being perturbed for the first time are exceedingly small; the much scarier prospect is of a long-period comet being kicked ever-so-slightly into Earth’s orbital path.

    The orbital path of Comet Swift-Tuttle, which passes perilously close to crossing Earth’s actual path around the Sun. Image credit: Howard of Teaching Stars, via

    Comet Swift-Tuttle, which gave rise to the Perseids, is the single most dangerous object known to humanity, and has a chance to impact us with more than 20 times the energy of the legendary dinosaur-killer in the 4400s. But we’ve got plenty of time until that might happen. In the meanwhile, take heart in the fact that except for Sun-directed asteroids and comets, we can see everything large that could come headed our way. And if we’re lucky enough to make it as a civilization for another thousand years or so, our technology will likely have advanced to the point where perhaps asteroid/comet deflection isn’t such a daunting task after all!

    The comet that gives rise to the Perseid meteor shower, Comet Swift-Tuttle, was photographed during its last pass into the inner Solar System in 1992. Image credit: NASA, of Comet Swift-Tuttle.

    Perhaps if it is, there’s always plan B: to clone Bruce Willis…

    See the full article here .

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    “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,” says Ethan

  • richardmitnick 10:28 am on October 22, 2016 Permalink | Reply
    Tags: , , , , Small Spacecraft Systems Virtual Institute (S3VI)   

    From NASA: “NASA Establishes the Small Spacecraft Systems Virtual Institute” 

    NASA image

    Oct. 21, 2016
    Loura Hall

    No image caption. No image credit.

    NASA announces the addition of its newest virtual institute to advance the field of small spacecraft systems. The Small Spacecraft Systems Virtual Institute (S3VI), hosted at NASA’s Ames Research Center in Moffett Field, California, will leverage the growing small spacecraft community, promote innovation, identify emerging technology opportunities, and provide an efficient channel for communication about small spacecraft systems with industry, academia, and other government agencies.

    “NASA sees enormous benefits from investing in research and technology development in small spacecraft systems, such as propulsion, that will be essential in advancing the commercial space sector,” said Steve Jurczyk, associate administrator for NASA’s Space Technology Mission Directorate (STMD). “Over the past several years, NASA has increased the generation of new, innovative applications of small spacecraft, with several mission directorates using small spacecraft to meet their goals.”

    STMD established the Small Spacecraft Technology Program in 2011 to develop and demonstrate the unique capabilities of small spacecraft to support science, exploration and space operations. The Science Mission Directorate (SMD) and the Human Exploration and Operations Mission Directorate (HEOMD) each are using small spacecraft for a range of activities: earth and space science measurements to help understand our environment; investigations of microgravity effects on organisms to enable the safe exploration of space; and robotic precursors to maximize the productive use of space.

    The S3VI will coordinate with key activities such as STMD’s Cube Quest Challenge and HEOMD’s CubeSat Launch Initiative (CLSI). These efforts will continue to offer opportunities for university students and industry to fly small spacecraft as auxiliary payloads on NASA launches.

    “The S3VI will provide the first one-stop shop for technical knowledge in the rapidly burgeoning small spacecraft technology fields,” said Jay Bookbinder, director of programs and projects at Ames. “This will result in more efficient development efforts, and enable smaller vendors to compete more effectively in this market.”

    Depending on the mission objective, a small spacecraft can range in size from a postage-stamp (under an ounce) up to the size of a refrigerator (about 400 pounds). Many recently launched NASA small spacecraft conform to the CubeSat standards – established by academia – in which a single cube (called a one-unit, or 1U) measures about 4 inches on each side, has an approximate volume of one quart, and weighs less than three pounds. The variety of sizes offers spacecraft capabilities tailored to specific science instruments, exploration sensors, or technology demonstrations.

    Over the next year, the S3VI will establish both a physical and virtual presence within NASA and the small spacecraft community at large. Strategic direction and tactical focus for the Institute will result from a series of community activities and workshops. The S3VI will engage with the small spacecraft communities, including academia, industry, and other government agencies to:

    Establish the Institute as the common portal into NASA for all small spacecraft activities. The Institute will capture information on small spacecraft activities and lessons learned; identify small spacecraft collaborative opportunities; and identify NASA points of contact for a variety of small spacecraft activities across the centers.

    Engage subject matter experts from across the small spacecraft communities to define the technical scope, policy issues and direction for the Institute.

    Host the Small Spacecraft Body of Knowledge (SSBK) as an online resource. This includes STMD’s Small Spacecraft Technology State of the Art report, a small spacecraft lessons learned library, a systems test data repository, reliability practices, etc.

    The S3VI portal will go live in early 2017, and is jointly sponsored by NASA’s Space Technology Mission Directorate and the Science Mission Directorate. The S3VI is hosted at and managed by NASA’s Ames Research Center in Moffett Field, California.

    For more information about the Space Technology Mission Directorate, visit:

    For more information about the Science Mission Directorate, visit:

    For more information about small satellites, visit:

    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 10:20 am on October 22, 2016 Permalink | Reply
    Tags: , , , From greenhouse gas to usable ethanol, ,   

    From Science Node: “From greenhouse gas to usable ethanol” 

    Science Node bloc
    Science Node

    19 Oct, 2016
    Morgan McCorkle

    ORNL scientists find a way to use nano-spike catalysts to convert carbon dioxide directly into ethanol.

    In a new twist to waste-to-fuel technology, scientists at the Department of Energy’s Oak Ridge National Laboratory (ORNL) have developed an electrochemical process that uses tiny spikes of carbon and copper to turn carbon dioxide, a greenhouse gas, into ethanol. Their finding, which involves nanofabrication and catalysis science, was serendipitous.

    Access mp4 video here .
    Serendipitous science. Looking to understand a chemical reaction, scientists accidentally discovered a method for converting combustion waste products into ethanol. The chance discovery may revolutionize the ability to use variable energy sources. Courtesy ORNL.

    “We discovered somewhat by accident that this material worked,” said ORNL’s Adam Rondinone, lead author of the team’s study published in ChemistrySelect. “We were trying to study the first step of a proposed reaction when we realized that the catalyst was doing the entire reaction on its own.”

    The team used a catalyst made of carbon, copper and nitrogen and applied voltage to trigger a complicated chemical reaction that essentially reverses the combustion process. With the help of the nanotechnology-based catalyst which contains multiple reaction sites, the solution of carbon dioxide dissolved in water turned into ethanol with a yield of 63 percent. Typically, this type of electrochemical reaction results in a mix of several different products in small amounts.

    “We’re taking carbon dioxide, a waste product of combustion, and we’re pushing that combustion reaction backwards with very high selectivity to a useful fuel,” Rondinone said. “Ethanol was a surprise — it’s extremely difficult to go straight from carbon dioxide to ethanol with a single catalyst.”

    The catalyst’s novelty lies in its nanoscale structure, consisting of copper nanoparticles embedded in carbon spikes. This nano-texturing approach avoids the use of expensive or rare metals such as platinum that limit the economic viability of many catalysts.

    “By using common materials, but arranging them with nanotechnology, we figured out how to limit the side reactions and end up with the one thing that we want,” Rondinone said.

    The researchers’ initial analysis suggests that the spiky textured surface of the catalysts provides ample reactive sites to facilitate the carbon dioxide-to-ethanol conversion.

    “They are like 50-nanometer lightning rods that concentrate electrochemical reactivity at the tip of the spike,” Rondinone said.

    Given the technique’s reliance on low-cost materials and an ability to operate at room temperature in water, the researchers believe the approach could be scaled up for industrially relevant applications. For instance, the process could be used to store excess electricity generated from variable power sources such as wind and solar.

    “A process like this would allow you to consume extra electricity when it’s available to make and store as ethanol,” Rondinone said. “This could help to balance a grid supplied by intermittent renewable sources.”

    The researchers plan to refine their approach to improve the overall production rate and further study the catalyst’s properties and behavior.

    ORNL’s Yang Song, Rui Peng, Dale Hensley, Peter Bonnesen, Liangbo Liang, Zili Wu, Harry Meyer III, Miaofang Chi, Cheng Ma, Bobby Sumpter and Adam Rondinone are coauthors on the study.

    The work was supported by DOE’s Office of Science and used resources at the ORNL’s Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.

    See the full article here .

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    Science Node is an international weekly online publication that covers distributed computing and the research it enables.

    “We report on all aspects of distributed computing technology, such as grids and clouds. We also regularly feature articles on distributed computing-enabled research in a large variety of disciplines, including physics, biology, sociology, earth sciences, archaeology, medicine, disaster management, crime, and art. (Note that we do not cover stories that are purely about commercial technology.)

    In its current incarnation, Science Node is also an online destination where you can host a profile and blog, and find and disseminate announcements and information about events, deadlines, and jobs. In the near future it will also be a place where you can network with colleagues.

    You can read Science Node via our homepage, RSS, or email. For the complete iSGTW experience, sign up for an account or log in with OpenID and manage your email subscription from your account preferences. If you do not wish to access the website’s features, you can just subscribe to the weekly email.”

  • richardmitnick 10:04 am on October 22, 2016 Permalink | Reply
    Tags: , , KIC 9832227, , Red nova   

    From New Scientist: “Double star may light up the sky as rare red nova in six years” 


    New Scientist

    21 October 2016
    Ken Croswell

    Is another one around the corner? NASA / Hubble Heritage Team (AURA/STScI)

    A dim binary star is behaving exactly as expected if it is about to explode as a “red nova“. If that happens, in 2022 or so it could shine as brightly as the North Star.

    Dozens of ordinary novae – the temporary flare-ups of white dwarf stars stealing gas from their companion star – explode in our galaxy every year. These novae turn blue.

    In recent years, however, astronomers have discovered a rare type of nova that turns red instead. At peak brightness, many red novae rival the most luminous stars in the galaxy.

    A red nova in 2008 gave us a clue as to why these explosions happen: observations made before the blast revealed that the nova was the result of two stars orbiting each other merging into one.

    The two stars were in a so-called contact binary, orbiting so closely that they touched. If Earth circled a contact binary, our suns would look like a fiery peanut.

    Despite their exotic appearance, contact binaries are common, with nearly 40,000 known in our galaxy. Now, new observations show that one, named KIC 9832227, could be about to explode as a red nova.

    Boom star

    “My colleagues like to call it the ‘Boom Star’,” says Larry Molnar of Calvin College in Grand Rapids, Michigan.

    The binary is roughly 1700 light years from Earth, in the constellation Cygnus. The two stars whirl around each other every 11 hours.

    In 2013 and 2014, Molnar’s team discovered two things about KIC 9832227 that suggest an imminent explosion: the orbital period is decreasing, and it’s doing so at an ever-faster rate.

    This is exactly what the contact binary that sparked the 2008 red nova did. The orbital period shrank because the two stars circled each other faster as they spiralled closer together.

    Unfortunately, other effects can mimic this decrease in orbital period. For example, a third star can pull the binary toward us so that its light takes less time to reach Earth, creating the illusion that the two stars are circling each other faster. So additional observations were needed to figure out what KIC 9832227 was likely to do.

    In late 2015, astronomers in Bulgaria observed the star with a 30-centimetre telescope, and found that its period is still shrinking at an ever-faster clip. “A stellar merger is a real possibility,” says Alexander Kurtenkov of the University of Sofia.

    Molnar’s team finds this trend persisting into 2016. “At this point, I think we have a serious candidate,” he says.

    His latest observations, made with 40-centimetre telescopes in Michigan and New Mexico, put the date of the potential explosion between 2021 and 2023. But he cautions that another three years of observations are required before he can rule out alternatives. By then, if the orbital period keeps shrinking faster and faster, an impending explosion will be very likely. If it calms down, there might be a different outcome.

    KIC 9832227 is currently 12th magnitude – visible only through a telescope. But if it brightens by 10 magnitudes, as the 2008 red nova did, it will be as bright as the North Star and the brightest stars of the Big Dipper, and easily visible to the naked eye.

    See the full article here .

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  • richardmitnick 8:57 am on October 22, 2016 Permalink | Reply
    Tags: , , ,   

    From Oxford: “The universe is expanding at an accelerating rate — or is it?” 

    U Oxford bloc

    Oxford University

    21 October 2016
    Stuart Gillespie

    Researchers analysed a database of supernovae — the spectacular thermonuclear explosions of dying stars. Image credit: University of Oxford; Shutterstock.

    Five years ago, the Nobel Prize in Physics was awarded to three astronomers for their discovery, in the late 1990s, that the universe is expanding at an accelerating pace.

    Their conclusions were based on analysis of Type Ia supernovae – the spectacular thermonuclear explosions of dying stars – picked up by the Hubble space telescope and large ground-based telescopes. It led to the widespread acceptance of the idea that the universe is dominated by a mysterious substance named ‘dark energy’ that drives this accelerating expansion.

    Now, a team of scientists led by Professor Subir Sarkar of Oxford University’s Department of Physics has cast doubt on this standard cosmological concept. Making use of a vastly increased data set – a catalogue of 740 Type Ia supernovae, more than ten times the original sample size – the researchers have found that the evidence for acceleration may be flimsier than previously thought, with the data being consistent with a constant rate of expansion.

    The study is published in the Nature journal Scientific Reports.

    Professor Sarkar, who also holds a position at the Niels Bohr Institute in Copenhagen, said: ‘The discovery of the accelerating expansion of the universe won the Nobel Prize, the Gruber Cosmology Prize, and the Breakthrough Prize in Fundamental Physics. It led to the widespread acceptance of the idea that the universe is dominated by “dark energy” that behaves like a cosmological constant – this is now the “standard model” of cosmology.

    ‘However, there now exists a much bigger database of supernovae on which to perform rigorous and detailed statistical analyses. We analysed the latest catalogue of 740 Type Ia supernovae – over ten times bigger than the original samples on which the discovery claim was based – and found that the evidence for accelerated expansion is, at most, what physicists call “3 sigma”. This is far short of the 5 sigma standard required to claim a discovery of fundamental significance.

    An analogous example in this context would be the recent suggestion for a new particle weighing 750 GeV based on data from the Large Hadron Collider at CERN. It initially had even higher significance – 3.9 and 3.4 sigma in December last year – and stimulated over 500 theoretical papers. However, it was announced in August that new data shows that the significance has dropped to less than 1 sigma. It was just a statistical fluctuation, and there is no such particle.’

    There is other data available that appears to support the idea of an accelerating universe, such as information on the cosmic microwave background [CMB] – the faint afterglow of the Big Bang – from the Planck satellite.

    CMB per ESA/Planck
    CMB per ESA/Planck

    However, Professor Sarkar said: ‘All of these tests are indirect, carried out in the framework of an assumed model, and the cosmic microwave background is not directly affected by dark energy. Actually, there is indeed a subtle effect, the late-integrated Sachs-Wolfe effect, but this has not been convincingly detected.

    ‘So it is quite possible that we are being misled and that the apparent manifestation of dark energy is a consequence of analysing the data in an oversimplified theoretical model – one that was in fact constructed in the 1930s, long before there was any real data. A more sophisticated theoretical framework accounting for the observation that the universe is not exactly homogeneous and that its matter content may not behave as an ideal gas – two key assumptions of standard cosmology – may well be able to account for all observations without requiring dark energy. Indeed, vacuum energy is something of which we have absolutely no understanding in fundamental theory.’

    Professor Sarkar added: ‘Naturally, a lot of work will be necessary to convince the physics community of this, but our work serves to demonstrate that a key pillar of the standard cosmological model is rather shaky. Hopefully this will motivate better analyses of cosmological data, as well as inspiring theorists to investigate more nuanced cosmological models. Significant progress will be made when the European Extremely Large Telescope makes observations with an ultrasensitive “laser comb” to directly measure over a ten to 15-year period whether the expansion rate is indeed accelerating.’

    See the full article here .

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    U Oxford campus

    Oxford is a collegiate university, consisting of the central University and colleges. The central University is composed of academic departments and research centres, administrative departments, libraries and museums. The 38 colleges are self-governing and financially independent institutions, which are related to the central University in a federal system. There are also six permanent private halls, which were founded by different Christian denominations and which still retain their Christian character.

    The different roles of the colleges and the University have evolved over time.

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