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  • richardmitnick 5:06 am on October 30, 2015 Permalink | Reply
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    From Gemini- “Time Delay in Lensed Quasar: First Fast Turnaround Result” 


    Gemini Observatory
    Gemini Observatory

    October 29, 2015

    A team of Norwegian and US astronomers, using data from Gemini North and the Nordic Optical Telescope (NOT), have measured the time delay in images of a quasar lensed by a foreground cluster of galaxies.

    Nordic Optical telescope
    Nordic Optical telescope interior

    The Gemini observations are the first published result obtained with the innovative Fast Turnaround (FT) mode of observing.

    A distant quasar may have its light split into multiple images by a foreground galaxy cluster that acts as a gravitational lens. The light travels along different paths of differing lengths to form each of these images. Quasars themselves are intrinsically variable, so the observed fading and brightening of each image happens at different observed times. Measuring these “time delays” yields tight constraints on the mass distribution in the lensing cluster, as well as the lensing geometry, and hence cosmology.

    The team monitored the redshift z=2.82 quasar SDSS J2222+2754 over the course of three years, using the NOT and Gemini+GMOS-N. They found a time delay of 48 and 722 days for two pairs of the quasar’s lensed images. The Gemini data were instrumental in refining the time delay measurements for the quasar image that leads the other image by ~ 2 years and hence predicts the behavior of other images of the quasar; continuing monitoring of the system will now allow further observations that take advantage of that 2 year peek into the future.

    Under Gemini’s FT mode, users can submit proposals every month and (if accepted) receive data 1-4 months after their initial proposal idea. The mode can be used for any kind of scientifically valuable project that needs just a few hours of observing time. Since the program’s launch in January, it has been used to follow up discoveries of new solar system objects, obtain data sets needed to complete projects, and also for short, self-contained programs. For more information, see the FT web pages: http://www.gemini.edu/sciops/observing-gemini/observing-modes/fast-turnaround.

    This work is available on Astro-ph at: http://arxiv.org/abs/1505.06187.

    Paper Abstract:

    We report first results from an ongoing monitoring campaign to measure time delays between the six images of the quasar SDSS J2222+2745, gravitationally lensed by a galaxy cluster. The time delay between A and B, the two most highly magnified images, is measured to be τAB=47.7±6.0 days (95% confidence interval), consistent with previous model predictions for this lens system. The strong intrinsic variability of the quasar also allows us to derive a time delay value of τCA=722±24 days between image C and A, in spite of modest overlap between their light curves in the current data set. Image C, which is predicted to lead all the other lensed quasar images, has undergone a sharp, monotonic flux increase of 60-75% during 2014. A corresponding brightening is firmly predicted to occur in images A and B during 2016. The amplitude of this rise indicates that time delays involving all six known images in this system, including those of the demagnified central images D-F, will be obtainable from further ground-based monitoring of this system during the next few years.

    See the full article here .

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    Gemini North
    Gemini North, Hawai’i

    Gemini South
    Gemini South, Chile
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    Gemini’s mission is to advance our knowledge of the Universe by providing the international Gemini Community with forefront access to the entire sky.

    The Gemini Observatory is an international collaboration with two identical 8-meter telescopes. The Frederick C. Gillett Gemini Telescope is located on Mauna Kea, Hawai’i (Gemini North) and the other telescope on Cerro Pachón in central Chile (Gemini South); together the twin telescopes provide full coverage over both hemispheres of the sky. The telescopes incorporate technologies that allow large, relatively thin mirrors, under active control, to collect and focus both visible and infrared radiation from space.

    The Gemini Observatory provides the astronomical communities in six partner countries with state-of-the-art astronomical facilities that allocate observing time in proportion to each country’s contribution. In addition to financial support, each country also contributes significant scientific and technical resources. The national research agencies that form the Gemini partnership include: the US National Science Foundation (NSF), the Canadian National Research Council (NRC), the Chilean Comisión Nacional de Investigación Cientifica y Tecnológica (CONICYT), the Australian Research Council (ARC), the Argentinean Ministerio de Ciencia, Tecnología e Innovación Productiva, and the Brazilian Ministério da Ciência, Tecnologia e Inovação. The observatory is managed by the Association of Universities for Research in Astronomy, Inc. (AURA) under a cooperative agreement with the NSF. The NSF also serves as the executive agency for the international partnership.

  • richardmitnick 12:37 pm on October 6, 2015 Permalink | Reply
    Tags: , , Gravitational Lensing,   

    From Hubble: “Can Hubble “see” gravity?” 

    NASA Hubble Telescope


    A Hubble image of a quadruple gravitational lens. The gravity of the galaxy at the center has re-directed the light of a background galaxy into four images; located above, below, left, and right-of-center. This distribution of lensed images is called an “Einstein Cross.” Credit: NASA, ESA, and STScI

    Oct 5, 2015
    No Writer Credit

    Gravity is the familiar force of nature responsible for the diverse motions of a baseball thrown high into the air, a planet orbiting a star, or a star orbiting within a galaxy. Astronomers have long observed such motions and deduced the amount of gravity, and therefore the amount of matter, present in the planet, star, or galaxy. When taken to the extreme, gravity can also create some intriguing visual effects that are well suited to Hubble’s high-resolution observations.

    [Albert]Einstein’s general theory of relativity expresses how very large mass concentrations distort the space around them. Light passing through that distorted space is re-directed, and can produce a variety of interesting imagery. The bending of light by gravity is similar to the bending of light by a glass lens, hence we call this effect gravitational lensing.

    The simplest type of gravitational lensing is called “point source” lensing. There is a single concentration of matter at the center, such as the dense core of a galaxy. The light of a distant galaxy is re-directed around this core, often producing multiple images of the background galaxy (see image accompanying this article). When the lensing approaches perfect symmetry, a complete or almost-complete circle of light is produced, called an Einstein ring. Hubble observations have helped to greatly increase the number of Einstein rings known to astronomers.

    More complex gravitational lensing arises in observations of massive clusters of galaxies. While the distribution of matter in a galaxy cluster generally does have a center, it is never circularly symmetric and can be significantly lumpy. Background galaxies are lensed by the cluster, with their images often appearing as short, thin “lensed arcs” around the outskirts of the cluster. Hubble’s images of galaxy clusters, such as Abell 2218 and Abell 1689, showed the large number and detailed distribution of these lensed images throughout massive galaxy clusters.

    This image shows the full overview of the galaxy cluster Abell 2218 and its gravitational lenses. This image was taken by Hubble in 1999 during the Early Release Observations made immediately after the Hubble Servicing Mission 3A.

    English: This new Hubble image shows galaxy cluster Abell 1689. It combines both visible and infrared data from Hubble’s Advanced Camera for Surveys (ACS) with a combined exposure time of over 34 hours (image on left over 13 hours, image on right over 20 hours) to reveal this patch of sky in greater and striking detail than in previous observations.

    This image is peppered with glowing golden clumps, bright stars, and distant, ethereal spiral galaxies. Material from some of these galaxies is being stripped away, giving the impression that the galaxy is dripping, or bleeding, into the surrounding space. Also visible are a number of electric blue streaks, circling and arcing around the fuzzy galaxies in the centre.
    These streaks are the telltale signs of a cosmic phenomenon known as gravitational lensing. Abell 1689 is so massive that it bends and warps the space around it, affecting how light from objects behind the cluster travels through space. These streaks are the distorted forms of galaxies that lie behind the cluster.
    Date 12 September 2013

    These lensed images also act as probes of the matter distribution in the galaxy cluster. Astronomers can measure the motions of the galaxies within a cluster to determine the total amount of matter in the cluster. The result indicates that the most of the matter in a galaxy cluster is not in the visible galaxies and does not emit light, and is thus called dark matter. The distribution of lensed images reflects the distribution of all matter, both visible and dark. Hence, Hubble’s images of gravitational lensing have been used to create maps of dark matter in galaxy clusters.

    In turn, a map of the matter in a galaxy cluster helps provide better understanding and analysis of the gravitationally lensed images. A model of the matter distribution can help identify multiple images of the same galaxy or be used to predict where the most distant galaxies are likely to appear in a galaxy cluster image. Astronomers work back and forth between the gravitational lenses and the cluster matter distribution to improve our understanding of both.

    On top of it all, gravitational lenses extend Hubble’s view deeper into the universe. Very distant galaxies are very faint. Gravitational lensing not only distorts the image of a background galaxy, it can amplify its light. Looking through a lensing galaxy cluster, Hubble can see fainter and more distant galaxies than otherwise possible. It is like having an extra lens that is the size of the galaxy cluster. The Frontier Fields project has examined multiple galaxy clusters, measured their lensing and matter distribution, and identified a collection of these most distant galaxies.

    While the effects of normal gravity are measurable in the motions of objects, the effects of extreme gravity are visible in images of gravitational lensing. The diverse, lensed images of crosses, rings, arcs, and more are both intriguing and informative. Gravitational lensing probes the distribution of matter in galaxies and clusters of galaxies, and enables observations of the distant universe. Hubble’s data will also provide a basis and guide for the future James Webb Space Telescope [JWST], whose infrared observations will push yet farther into the cosmos.

    NASA Webb Telescope

    The distorted imagery of gravitational lensing often is likened to the distorted reflections of funhouse mirrors, but don’t take that comparison too far. Hubble’s images of gravitational lensing provide a wide range of serious science.

    See the full article here .

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

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  • richardmitnick 9:54 am on September 26, 2015 Permalink | Reply
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    From Kavli IPMU: “Discovery of potential gravitational lenses shows citizen science value” 


    The Kavli Foundation

    Kavli IPMU
    Kavli IMPU

    September 24, 2015
    Press Contact

    Motoko Kakubayashi
    Press officer, Kavli Institute for the Physics and Mathematics of the Universe
    E: press@ipmu.jp
    T: +81-4-7136-5980
    F: +81-4-7136-4941

    Research Contact

    Anupreeta More
    Project Researcher, Kavli Institute for the Physics and Mathematics of the Universe
    E: anupreeta.more@ipmu.jp

    Figure 1: 29 gravitational lens candidates found through Space Warps (credit: Space Warps, Canada-France-Hawaii Telescope Legacy Survey)

    Around 37,000 citizen scientists combed through 430,000 images to help an international team of researchers to discover 29 new gravitational lens candidates through SpaceWarps, an online classification system which guides citizen scientists to become lens hunters.

    Gravitational lens systems are massive galaxies that act like special lenses through their gravity, bending the light coming from a distant galaxy in the background and distorting its image. Dark matter around these massive galaxies also contributes to this lensing effect, and so studying these gravitational lenses gives scientists a way to study this exotic matter that emits no light.

    Since gravitational lenses are rare, only about 500 of them have been discovered to date, and the universe is enormous, it made sense for researchers to call on an extra pair of eyes to help scour through the mountain of images taken from the Canada-France-Hawaii Telescope [CFHT] Legacy Survey (CFHTLS).

    CFHT nterior

    Details of the discoveries will be published in Monthly Notices of the Royal Astronomical Society.

    “Computer algorithms have been somewhat successful in identifying gravitational lenses, but they can miss lensed images that appear similar to other features commonly found in galaxies, for example the blue spiral arms of a spiral galaxy,” said Anupreeta More, co-principal investigator of Space Warps and project researcher at the University of Tokyo’s Kavli Institute for the Physics and Mathematics of the Universe.

    “All that was needed was the ability to recognise patterns of shapes and colours,” said citizen scientist and paper co-author Christine Macmillan from Scotland. “It was fascinating to look at galaxies so far away, and realize that there is another behind it, even further away, whose light gets distorted in an arc.”

    Not only did this project give the public a chance to make scientific discoveries, it also gave them a chance to develop as researchers themselves. “I benefited from this project with an increase of my knowledge and some experience on making models of lenses,” said citizen scientist and paper co-author Claude Cornen from France.

    More, and two other collaborators, Phil Marshall at the Kavli Institute for Particle Astrophysics and Cosmology, Stanford University, and Aprajita Verma at the Department of Physics, University of Oxford, are co-principal investigators of Space Warps, which taps into the unique strength of humans in analysing visual information essential for finding gravitational lenses.

    The team will now move onto studying some of the interesting gravitational lens candidates by observing them with telescopes to uncover some of the mysteries related to dark matter. They are keen to work together with more volunteers in the near future as they are preparing new images from other ongoing imaging surveys to discover many more lenses.

    Figure 2: How one galaxy’s image appears distorted due to another galaxy (credit: Kavli IPMU)

    Paper details

    Journal: Monthly Notices of the Royal Astronomical Society (MNRAS)

    Title: Space Warps II. New Gravitational Lens Candidates from the CFHTLS Discovered through Citizen Science

    To download preprint, click here.
    Useful Links

    All images can be downloaded from this page: http://web.ipmu.jp/press/20150903-SpaceWarps

    Full list of citizens who took part: http://spacewarps.org/#/projects/CFHTLS/contributors

    To download preprint of another paper also accepted to MNRAS journal that describes the details of Space Warps, click here.

    See the full article here .

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    Kavli IPMU (Kavli Institute for the Physics and Mathematics of the Universe) is an international research institute with English as its official language. The goal of the institute is to discover the fundamental laws of nature and to understand the Universe from the synergistic perspectives of mathematics, astronomy, and theoretical and experimental physics. The Institute for the Physics and Mathematics of the Universe (IPMU) was established in October 2007 under the World Premier International Research Center Initiative (WPI) of the Ministry of Education, Sports, Science and Technology in Japan with the University of Tokyo as the host institution. IPMU was designated as the first research institute within the University of Tokyo Institutes for Advanced Study (UTIAS) in January 2011. It received an endowment from The Kavli Foundation and was renamed the “Kavli Institute for the Physics and Mathematics of the Universe” in April 2012. Kavli IPMU is located on the Kashiwa campus of the University of Tokyo, and more than half of its full-time scientific members come from outside Japan. http://www.ipmu.jp/

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    The Kavli Foundation, based in Oxnard, California, is dedicated to the goals of advancing science for the benefit of humanity and promoting increased public understanding and support for scientists and their work.

    The Foundation’s mission is implemented through an international program of research institutes, professorships, and symposia in the fields of astrophysics, nanoscience, neuroscience, and theoretical physics as well as prizes in the fields of astrophysics, nanoscience, and neuroscience.

  • richardmitnick 10:50 am on July 19, 2015 Permalink | Reply
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    From SPACE.com: “Newfound Alien Planet Is One of the Farthest Ever Detected” 

    space-dot-com logo


    April 16, 2015
    Elizabeth Howell

    NASA’s Spitzer Space Telescope co-discovered an exoplanet more than 13,000 light-years from Earth, far from where most known exoplanets are Credit: NASA/JPL-Caltech

    A NASA telescope has co-discovered one of the most distant planets ever identified: a gas giant about 13,000 light-years away from Earth.

    The technique used by the Spitzer Space Telescope, called microlensing, is so new that it has only yielded about 30 planet discoveries so far. But the telescope’s potential for finding far-away worlds is vast, NASA said in a statement. And as astronomers begin to chart the location of these distant bodies, it will provide a sense of where planets are distributed in Earth’s Milky Way galaxy.

    NASA Spitzer Telescope

    “We don’t know if planets are more common in our galaxy’s central bulge or the disk of the galaxy, which is why these observations are so important,” Jennifer Yee, of the Harvard-Smithsonian Center for Astrophysics, said in a NASA statement. Yee is the lead author on one of three new papers describing the discovery.

    An infographic showing how NASA’s Spitzer Space Telescope works with ground-based telescopes to find distant exoplanets, using a technique called microlensing. Credit: NASA/JPL-Caltech

    Magnified starlight

    Microlensing happens when one star travels in front of another from the perspective of an observer (in this case, on Earth). When this happens, the gravity of the star in front magnifies the light of the star behind it, acting like a lens. Should the star in front have a planet, that planet would create a “blip” during the magnification, NASA said in the statement.

    The challenge, however, is pinning down how far away the closer star (and its planet) is from Earth. Microlensing tends to magnify the star behind, but usually the star in front is invisible to observers. That’s why about half of the 30 or so planets found with microlensing (including a few Tatooine-like planets) are at unknown distances from Earth.

    To overcome the distance problem, astronomers used the Spitzer telescope in concert with the Polish Optical Gravitational Lensing Experiment (OGLE) Warsaw Telescope at the Las Campanas Observatory in Chile. OGLE routinely does microlensing investigations, but for Spitzer, this was the first time the long-running telescope had successfully used the technique to find a planet.

    OGLE Warsaw Telescope
    OGLE Warsaw telescope interior
    Polish Optical Gravitational Lensing Experiment (OGLE) Warsaw Telescope

    Quick telescope work

    Prominent telescopes like Spitzer are usually fully booked with other astronomical observations. This makes it difficult to respond quickly when the astronomical community is alerted about a microlensing event, which lasts only 40 days on average. Spitzer officials, however, have worked to do these observations as early as three days after an event is announced.

    The new planet’s microlensing event was quite long, roughly 150 days.

    Spitzer orbits the sun from a position behind Earth (about 128 million miles or 207 million kilometers away from its home planet, further than the Earth-sun distance). This vast distance from its home planet means the telescope sees microlensing events occur at a slightly different time than do telescopes on Earth.

    Spitzer spotted the “blip” in the magnification about 20 days before OGLE did. By comparing the delay between what Spitzer and OGLE saw, astronomers could calculate the planet’s distance from Earth. Once they knew that measure, they were able to estimate the planet’s mass, which is roughly half that of Jupiter.

    This is the first time Spitzer found a planet using microlensing, but it comes after 22 previous attempts with OGLE and other telescopes on the ground. Astronomers forecast Spitzer will examine 120 more microlensing events this summer.

    So far, microlensing has helped astronomers find 30 planets at distances as far as 25,000 light-years away from Earth. That’s in addition to the more than 1,000 closer worlds discovered by the planet-hunting Kepler space telescope and ground-based observatories using other techniques. Astronomers are using the microlensing events to seek out planets in the central “bulge” of the Milky Way, a spot where stars are more densely packed and tend to cross more often.

    See the full article here.

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  • richardmitnick 9:24 am on May 29, 2015 Permalink | Reply
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    From FNAL- “Frontier Science Result: South Pole Telescope Gravitational lensing of the cosmic microwave background by galaxy clusters” 

    FNAL Home

    Fermilab is an enduring source of strength for the US contribution to scientific research world wide.

    May 29, 2015
    Scott Dodelson

    The left panel shows a simulated map of an unlensed cosmic microwave background. The center panel shows the same map if a large galaxy cluster were along the line of sight. Note that the scale on these two panels goes to 100 microKelvin. The right panel shows the difference between the first two panels. The scale is now down to 10 microKelvin. (Plots are in units of arcminutes.) Image: Antony Lewis and Lindsay King, Institute of Astronomy

    The photons that make up the cosmic microwave background (CMB) have traversed the universe almost freely for 13.8 billion years, thereby carrying information about the state of the universe when it was only 380,000 years old.

    Cosmic Background Radiation Planck
    CMB per ESA/Planck

    ESA Planck

    “Almost freely” refers to two ways that these photons are disturbed along their long journeys: They are sometimes scattered by hot electrons and they are deflected by deep gravitational wells.

    It is this latter deflection, called gravitational lensing, that offers immense promise as a tool to weigh massive objects such as galaxy clusters. Clusters are very important because their abundance offers insight into why the universe is currently accelerating. Extracting this insight, though, requires careful estimates of the masses of clusters. There are currently several techniques in play: X-ray emission, galaxy counts in the clusters, distortions of the shapes of background galaxies and the signal imprinted on the CMB by hot electrons in clusters.

    Lensing of the CMB provides a new way to measure cluster masses, one that has just been demonstrated. A simulated signal from one cluster is shown above. Each panel represents about 35 square arcminutes, about 20 times smaller than the moon, so a CMB experiment must have excellent resolution to see the effect. Cluster lensing is the difference between the left and center panels, shown in the right panel. The signal is roughly several microKelvin, much smaller than the typical hot and cold spots that have made the CMB famous. So the resolution must be coupled with exquisite sensitivity.

    Large ground-based telescopes such as the 10-meter South Pole Telescope [SPT] are beginning to attain this dual capability.

    South Pole Telescope

    The noise levels are still too high to measure lensing by a single cluster, so the SPT team performed a likelihood analysis using 513 clusters, detected over three years of the telescope’s operation, to measure the weighted mass. The result was a 3-sigma measurement of the lensing of the CMB, with the mass consistent with those obtained with other methods. A paper on this result has recently been accepted for publication in The Astrophysical Journal.

    The team is now optimistic that this effect will lead to competitive constraints on cluster masses with upcoming surveys, such as SPT-3G and CMB-S4.

    See the full article here.

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    Fermilab Campus

    Fermi National Accelerator Laboratory (Fermilab), located just outside Batavia, Illinois, near Chicago, is a US Department of Energy national laboratory specializing in high-energy particle physics. Fermilab is America’s premier laboratory for particle physics and accelerator research, funded by the U.S. Department of Energy. Thousands of scientists from universities and laboratories around the world
    collaborate at Fermilab on experiments at the frontiers of discovery.

  • richardmitnick 2:54 pm on December 6, 2013 Permalink | Reply
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    From NASA/ESA Hubblecast 70: Gravitational Lensing 

    Watch Hubblecast 70 to learn about gravitational lensing.

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

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  • richardmitnick 12:33 pm on March 5, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “Gravitational telescope creates space invader mirage” 

    5 March 2013
    Nicola Guttridge
    Garching, Germany
    Tel: +49-89-3200-6855
    Email: nguttrid@partner.eso.org

    The NASA/ESA Hubble Space Telescope is one of the most powerful available to astronomers, but sometimes it too needs a helping hand. This comes in the form of Einstein’s general theory of relativity, which makes galaxy clusters act as natural lenses, amplifying the light coming from very distant galaxies.


    Abell 68, pictured here in infrared light, is one of these galaxy clusters, and it greatly boosts the power of Hubble, extending the telescope’s ability to observe distant and faint objects [1]. The fuzzy collection of blobs in the middle and upper left of the image is a swarm of galaxies, each with hundreds of billions of stars and vast amounts of dark matter.

    The effect of this huge concentration of matter is to deform the fabric of spacetime, which in turn distorts the path that light takes when it travels through the cluster. For galaxies that are even further away than the cluster — which is already at the impressive distance of two billion light-years — and which are aligned just right, the effect is to turn galaxies that might otherwise be invisible into ones that can be observed with relative ease.

    Although the resulting images projected to us of these distant galaxies are typically heavily deformed, this process, called gravitational lensing, is a hugely valuable tool in cosmology, the branch of astronomy which deals with the origins and evolution of the Universe.

    [1] Hubble’s ability to see distant objects will be enhanced with the start of Frontier Fields in the near future, an observing campaign that aims to combine the power of Hubble with the natural gravitational telescopes of high-magnification clusters of galaxies — as seen here with Abell 68. This will enable Hubble to see objects that would ordinarily be too distant or faint for it to see. Frontier Fields will study six different galaxy clusters to give us a sneak preview of the very earliest stars and galaxies, before the launch of the James Webb Space Telescope in 2018.”

    See the full article here.

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

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  • richardmitnick 3:24 pm on November 16, 2012 Permalink | Reply
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    From NASA: “NASA Great Observatories Find Candidate for Most Distant Galaxy Yet Known” 

    By combining the power of NASA’s Hubble Space Telescope, Spitzer Space Telescope, and one of nature’s own natural “zoom lenses” in space, astronomers have set a new distance record for finding the farthest galaxy yet seen in the universe.

    The diminutive blob, which is only a tiny fraction of the size of our Milky Way galaxy, offers a peek back into a time when the universe was 3 percent of its present age of 13.7 billion years. The newly discovered galaxy, named MACS0647-JD, is observed 420 million years after the big bang. Its light has traveled 13.3 billion years to reach Earth.


    This is the latest discovery from a large program that uses natural zoom lenses to reveal distant galaxies in the early universe. The Cluster Lensing And Supernova survey (CLASH) with Hubble is using massive galaxy clusters as cosmic telescopes to magnify distant galaxies behind them, an effect called gravitational lensing.

    Along the way, 8 billion years into its journey, this light took a detour along multiple paths around the massive galaxy cluster MACS J0647+7015. Due to the gravitational lensing, the CLASH research team, an international group led by Marc Postman of the Space Telescope Science Institute in Baltimore, Md., observed three magnified images of MACS0647-JD with the Hubble telescope. The cluster’s gravity boosted the light from the faraway galaxy, making the images appear approximately eight, seven, and two times brighter than they otherwise would, enabling astronomers to detect them more efficiently and with greater confidence. Without the cluster’s magnification powers, astronomers would not have seen this remote galaxy.

    ‘This cluster does what no manmade telescope can do,’ said Postman. ‘Without the magnification, it would require a Herculean effort to observe this galaxy.'”

    The object is so small it may be in the first embryonic steps of forming an entire galaxy. An analysis shows that the galaxy is less than 600 light-years wide. Based on observations of somewhat closer galaxies, astronomers estimate that a typical galaxy of that epoch should be about 2,000 light-years wide. For comparison, the Large Magellanic Cloud, a companion dwarf galaxy to the Milky Way, is 14,000 light-years wide. Our Milky Way is 150,000 light-years across.”

    Se the full article here.

    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) conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, Inc., in Washington, D.C.

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