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  • richardmitnick 1:46 pm on August 15, 2013 Permalink | Reply
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    From CANDLES: “What Did Galaxies Look Like at Cosmic High Noon?” 

    Hubble Candles

    Thursday, August 15, 2013
    Joel Primack

    “The rate of star formation was highest about 10 billion years ago, a period that CANDELS astronomers call ‘Cosmic High Noon.’ The redshift then was about 2, which means that the universe has expanded by a factor of three since then in each of the three spatial dimensions, so it was 3x3x3 = 27 times denser back then. The universe was also much brighter, with so many galaxies so much closer together forming lots of short-lived massive stars, which shine much more brightly than lower-mass long-lived stars like our sun.

    What did those early galaxies look like, and how did they evolve into the galaxies we see around us today? Answering that question is one of the most important goals of the CANDELS survey. The infrared capability of the Wide Field Camera 3 (WFC3), installed in the last astronaut visit to Hubble Space Telescope in 2009, gives us the ability to see galaxies at redshift 2 in the wavelengths of visible light. Visible light, with wavelengths ranging from blue at 0.4 to red at 0.7 microns (a micron is a millionth of a meter), gives us crucial information about the long-lived stars in galaxies. The wavelengths of light emitted at redshift 2 expand by a factor of 3, just as space does, so visible wavelengths expand to 1.2 to 2.1 microns. WFC3 allows us to make images at wavelengths as long as 1.7 microns, while WFC3 and other HST cameras make images at shorter wavelengths that allow us to trace recent star formation because such ultraviolet light is emitted by short-lived massive stars.

    images
    Simulated galaxy at redshift 2.1 from a high-resolution cosmological simulation. Top: rest-frame optical
    image from the Sunrise computer code, taking in account stellar evolution and the scattering and absorption
    of light by dust and subsequent dust re-radiation. Bottom: The same simulated galaxy, as seen by Hubble
    Space Telescope in V (visual light) and H (1.5-1.7 micron infrared wavelengths) bands. Because of the
    redshift of the radiation from this galaxy, what HST sees as V-band light was emitted as ulraviolet in the
    galaxy rest frame, which mainly traces new star formation, while what HST sees as H-band light was emitted
    as red light, which traces the older stellar population in the high-redshift galaxy. Note that the V-band image
    is clumpy, which is also often the case for real galaxies at these redshifts. Image Credit: Joel Primack

    One of the things that we have found is that star-forming galaxies at redshift 2 were often rather clumpy, unlike the rather smooth Milky Way and other nearby galaxies. My colleagues and I have been simulating the formation and evolution of galaxies, and our simulations often also look rather clumpy, with giant star-forming regions in their disks. The clumps occur partly because the galaxies have so much gas in their disks that the disks become gravitationally unstable and break up into clumps of gas that rapidly form stars. We have been comparing the observed and simulated galaxies systematically, and we have been gratified to find that they appear fairly similar in their sizes and shapes, as well as their clumpiness.”

    See the full article here.

    About the CANDELS blog

    In late 2009, the Hubble Space Telescope began an ambitious program to map five carefully selected areas of the sky with its sensitive near-infrared camera, the Wide-Field Camera 3. The observations are important for addressing a wide variety of questions, from testing theories for the birth and evolution of galaxies, to refining our understanding of the geometry of the universe.

    This is a research blog written by people involved in the project. We aim to share some of the excitement of working at the scientific frontier, using one of the greatest telescopes ever built. We will also share some of the trials and tribulations of making the project work, from the complications of planning and scheduling the observations to the challenges of trying to understand the data. Along the way, we may comment on trends in astronomy or other such topics.

    CANDELS stands for the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey. It builds on the legacy of the Hubble Deep Field, as well as the wider-area surveys called GOODS, AEGIS, COSMOS, and UKIDSS UDS. The CANDELS observations are designed to search for galaxies within about a billion years of the big bang, study galaxies at cosmic high-noon about 3 billion years after the big bang – when star-formation and black hole growth were at their peak intensity – and discover distant supernovae for refining our understanding of cosmic acceleration. You can find more details, and download the CANDELS data, from the CANDELS website.

    You can also use the Hubble Legacy Archive to view the CANDELS images.


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  • richardmitnick 10:15 am on August 15, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “Hubble explores the origins of modern galaxies” 

    15 August 2013
    Contacts

    BoMee Lee
    University of Massachusetts
    Massachusetts, USA
    Tel: +1-413-545-0731
    Email: bomee@astro.umass.edu

    Arjen van der Wel
    Max Planck Institute for Astronomy
    Heidelberg, Germany
    Tel: +49-6221-528-461
    Email: vdwel@mpia.de

    Mauro Giavalisco
    University of Massachusetts
    Massachusetts, USA
    Tel: +1-413-545-4767
    Email: mauro@astro.umass.edu

    Nicky Guttridge
    Hubble/ESA
    Garching, Germany
    Tel: +49-89-3200-6855
    Email: nguttrid@partner.eso.org

    Astronomers see true shapes of galaxies 11 billion years back in time

    Astronomers have used observations from Hubble’s CANDELS survey to explore the sizes, shapes, and colours of distant galaxies over the last 80% of the Universe’s history. In the Universe today galaxies come in a variety of different forms, and are classified via a system known as the Hubble Sequence — and it turns out that this sequence was already in place as early as 11 billion years ago.

    candles

    The Hubble Sequence classifies galaxies according to their morphology and star-forming activity, organising them into a cosmic zoo of spiral, elliptical, and irregular shapes with whirling arms, fuzzy haloes and bright central bulges. Two main types of galaxy are identified in this sequence: elliptical and spiral, with a third type, lenticular, settling somewhere between the two.

    This accurately describes what we see in the region of space around us, but how does galaxy morphology change as we look further back in time, to when the Universe was very young?

    ‘This is a key question: when and over what timescale did the Hubble Sequence form?’ says BoMee Lee of the University of Massachusetts, USA, lead author of a new paper exploring the sequence. ‘To do this you need to peer at distant galaxies and compare them to their closer relatives, to see if they too can be described in the same way.’

    The astronomers used Hubble to look 11 billion years back in time to when the Universe was very young, exploring the anatomy of distant galaxies.

    While it was known that the Hubble Sequence holds true as far back as around 8 billion years ago, these new observations push a further 2.5 billion years back in cosmic time, covering a huge 80% of the past history of the Universe. Previous studies had also reached into this epoch of the cosmos to study lower-mass galaxies, but none had conclusively also looked at large, mature galaxies like the Milky Way. The new CANDELS observations confirm that all galaxies this far back — big and small alike — fit into the different classifications of the sequence.

    ‘This is the only comprehensive study to date of the visual appearance of the large, massive galaxies that existed so far back in time,’ says co-author Arjen van der Wel of the Max Planck Institute for Astronomy in Heidelberg, Germany. ‘The galaxies look remarkably mature, which is not predicted by galaxy formation models to be the case that early on in the history of the Universe.’

    The galaxies at these earlier times appear to be split between blue star-forming galaxies with a complex structure — including discs, bulges, and messy clumps — and massive red galaxies that are no longer forming stars, as seen in the nearby Universe.

    Galaxies as massive as the Milky Way or more are rather rare in the young Universe. This scarcity has prevented previous studies from being able to gather a large enough sample of mature galaxies to properly describe their characteristics.

    What was needed was a systematic set of observations such as those from Hubble’s CANDELS survey, which was large enough to allow the astronomers to analyse a larger number of these galaxies consistently, and in detail. With Hubble’s Wide Field Camera 3 (WFC3), the astronomers were able to observe in the infrared part of the spectrum to see how the galaxies appeared in their visible rest-frame [4], which is easier to compare with galaxies in our neighbourhood.

    ‘The huge CANDELS dataset was a great resource for us to use in order to consistently study ancient galaxies in the early Universe,’ concludes Lee. ‘And the resolution and sensitivity of Hubble’s WFC3 is second to none in the infrared wavelengths needed to carry out this study. The Hubble Sequence underpins a lot of what we know about how galaxies form and evolve — finding it to be in place this far back is a significant discovery.'”

    See the full article, with more images and explanatory notes 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 1:43 pm on August 12, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “Stars fleeing a cosmic crash” 

    “Astronomical pictures sometimes deceive us with tricks of perspective. Right in the centre of this image, two spiral galaxies appear to be suffering a spectacular collision, with a host of stars appearing to flee the scene of the crash in a chaotic stampede.

    stars
    Credit: ESA/Hubble & NASA Luca Limatola
    Release date: 12 August 2013, 10:00

    However, this is just a trick of perspective. It is true that two spiral galaxies are colliding, but they are millions of light-years away, far beyond the cloud of blue and red stars near the merging spiral. This sprinkling of stars is actually an isolated, irregular dwarf galaxy named ESO 489-056. The dwarf galaxy is actually much more distant than many bright stars in the foreground of the image, which are located much closer to us, in the Milky Way.

    ESO 489-056 is located 16 million light-years from Earth in the constellation of Canis Major (The Greater Dog), in our local Universe. It is composed of a few billion red and blue stars — a very small number when compared to galaxies like the Milky Way, which is estimated to contain around 200 to 400 billion stars, or the Andromeda Galaxy, which contains a mind-boggling one trillion.

    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 9:40 am on August 9, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “The Lure of the Rings” 

    “Resembling a diamond-encrusted bracelet, a ring of brilliant blue star clusters wraps around the yellowish nucleus of what was once a normal spiral galaxy in this new image from the NASA/ESA Hubble Space Telescope (HST). This image is being released to commemorate the 14th anniversary of Hubble’s launch on April 24, 1990 and its deployment from the space shuttle Discovery on April 25, 1990.

    rg
    AM 0644-741
    Release date: 22 April 2004, 15:03

    The sparkling blue ring is 150,000 light-years in diameter, making it larger than our entire home galaxy, the Milky Way. The galaxy, cataloged as AM 0644-741, is a member of the class of so- called ‘ring galaxies.’ It lies 300 million light-years away in the direction of the southern constellation Dorado.”

    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 12:14 pm on August 7, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “Hubble Finds ‘Smoking Gun’ After Gamma-Ray Blast” 

    CONTACT
    Donna Weaver / Ray Villard
    Space Telescope Science Institute, Baltimore, Md.
    410-338-4493 / 410-339-4514
    dweaver@stsci.edu / villard@stsci.edu

    Nial Tanvir
    University of Leicester, Leicester, U.K.
    011-44-7980-136499
    nrt3@le.ac.uk

    Andy Fruchter
    Space Telescope Science Institute, Baltimore, Md.
    410-338-5018
    fruchter@stsci.edu

    NASA’s Hubble Space Telescope has provided the strongest evidence yet that short-duration gamma-ray bursts are triggered by the merger of two small, super-dense stellar objects, such as a pair of neutron stars or a neutron star and a black hole.

    grb
    Credit: NASA, ESA, N. Tanvir (University of Leicester), A. Fruchter (STScI), and A. Levan (University of Warwick)
    Release Date: July 30, 2013

    The definitive evidence came from Hubble observations in near-infrared light of the fading fireball produced in the aftermath of a short gamma-ray burst (GRB). The afterglow reveals for the first time a new kind of stellar blast called a kilonova, an explosion predicted to accompany a short-duration GRB.

    A kilonova is about 1,000 times brighter than a nova, which is caused by the eruption of a white dwarf. Such a stellar blast, however, is only 1/10th to 1/100th the brightness of a typical supernova, the self-detonation of a massive star.

    Gamma-ray bursts are mysterious flashes of intense high-energy radiation that appear from random directions in space. Short-duration blasts last at most a few seconds, but they sometimes generate faint afterglows in visible and near-infrared light that continue for several hours or days.

    The afterglows have helped astronomers determine that GRBs lie in distant galaxies. The cause of short-duration GRBs, however, remains a mystery. The most popular theory is that astronomers are witnessing the energy released as two compact objects crash together. But, until now, astronomers have not gathered enough strong evidence to prove it, say researchers.

    A team of researchers led by Nial Tanvir of the University of Leicester in the United Kingdom has used Hubble to study a recent short-duration burst in near-infrared light. The observations revealed the fading afterglow of a kilonova explosion, providing the “smoking gun” evidence for the merger hypothesis.

    ‘This observation finally solves the mystery of the origin of short gamma-ray bursts,’ Tanvir said. ‘Many astronomers, including our group, have already provided a great deal of evidence that long-duration gamma-ray bursts (those lasting more than two seconds) are produced by the collapse of extremely massive stars. But we only had weak circumstantial evidence that short bursts were produced by the merger of compact objects. This result now appears to provide definitive proof supporting that scenario.’

    In a recent science paper Jennifer Barnes and Daniel Kasen of the University of California, Berkeley, and the Lawrence Berkeley National Laboratory presented new calculations predicting how kilonovas should look. They predicted that the same hot plasma producing the radiation will also act to block the visible light, causing the gusher of energy from the kilonova to flood out in near-infrared light over several days.

    An unexpected opportunity to test this model came on June 3 when NASA’s Swift Space Telescope picked up the extremely bright gamma-ray burst, cataloged as GRB 130603B, in a galaxy located almost 4 billion light-years away. Although the initial blast of gamma rays lasted just one-tenth of a second, it was roughly 100 billion times brighter than the subsequent kilonova flash.

    The visible-light afterglow was detected at the William Herschel Telescope and its distance was determined with the Gran Telescopio Canarias, both located in the Canary Islands.

    ‘We quickly realized this was a chance to test Barnes’ and Kasen’s new theory by using Hubble to hunt for a kilonova in near-infrared light,’ Tanvir said. The calculations suggested that the light would most likely be brightest in near-infrared wavelengths about 3 to 11 days after the initial blast. The researchers needed to act quickly before the light faded, so they requested Director’s Discretionary Observing Time with Hubble’s Wide Field Camera 3.

    On June 12-13 Hubble searched the location of the initial burst, spotting a faint red object. An independent analysis of the data from another research team confirmed the detection. Subsequent Hubble observations three weeks later, on July 3, revealed that the source had faded away, therefore providing the key evidence it was the fireball from an explosive event.”

    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 11:00 am on August 6, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “A star’s colourful final splash” 

    “The Hubble Space Telescope captured this beautiful image of NGC 6326, a planetary nebula with glowing wisps of outpouring gas that are lit up by a central star nearing the end of its life.

    ngc
    Credit: NASA/ESA Hubble
    Release date: 28 June 2010, 10:00

    When a star ages and the red giant phase of its life comes to an end, it starts to eject layers of gas from its surface leaving behind a hot and compact white dwarf. Sometimes this ejection results in elegantly symmetric patterns of glowing gas, but NGC 6326 is much less structured. This object is located in the constellation of Ara, the Altar, about 11 000 light-years from Earth.

    Planetary nebulae are one of the main ways in which elements heavier than hydrogen and helium are dispersed into space after their creation in the hearts of stars. Eventually some of this outflung material may form new stars and planets. The vivid red and blue hues in this image come from the material glowing under the action of the fierce ultraviolet radiation from the still hot central star.

    This picture was created from images taken using the Hubble Space Telescope’s Wide Field Planetary Camera 2. The red light was captured through a filter letting through the glow from hydrogen gas (F658N). The blue glow comes from ionised oxygen and was recorded through a green filter (F502N). The green layer of the image, which shows the stars well, was taken through a broader yellow filter (F555W). The total exposure times were 1400 s, 360 s and 260 s respectively. The field of view is about 30 arcseconds across.

    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 1:37 pm on August 5, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “Sunset in Mordor” 

    “Don’t be fooled by the title; the mysterious, almost mystical bright light emerging from these thick, ominous clouds is actually a telltale sign of star formation. Here, a very young star is being born in the guts of the dark cloud LDN 43 — a massive blob of gas, dust, and ices, gathered 520 light-years from Earth in the constellation of Ophiuchus (The Serpent Bearer).

    pro
    Release date: 5 August 2013, 10:00
    Credit: NASA/ESA Hubble

    This image is based on data gathered by the NASA/ESA Hubble Space Telescope. A version of this image was entered into the Hubble’s Hidden Treasures image processing competition by contestant Judy Schmidt.

    Stars are born from cosmic dust and gas, which floats freely in space until gravity forces it to bind together. The hidden newborn star in this image, revealed only by light reflected onto the plumes of the dark cloud, is named RNO 91. It is what astronomers call a pre-main sequence star, meaning that it has not yet started burning hydrogen in its core.

    The energy that allows RNO 91 to shine comes from gravitational contraction. The star is being compressed by its own weight until, at some point, a critical mass will be reached and hydrogen, its main component, will begin to fuse together, releasing huge amounts of energy in the process. This will mark the beginning of adulthood for the star. But even before this happens the adolescent star is bright enough to shine and generate powerful stellar winds, emitting intense X-ray and radio emission.

    RNO 91 is a variable star around half the mass of the Sun. Astronomers have been able to observe the existence of a dusty, icy disc surrounding it, stretching out to over 1700 times the distance from Earth to the Sun. It is believed that this disc may host protoplanets — planets in the process of being formed — and will eventually evolve into a fully-fledged planetary system.”

    ec
    A photogenic variable star, Eta Carinae, embedded in the Carina Nebula.

    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 12:25 pm on July 30, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “Doing cartwheels to celebrate the end of an era” 

    Article is undated.
    No Writer Credit

    “An image of the Cartwheel Galaxy taken with the NASA/ESA Hubble Space Telescope has been reprocessed using the latest techniques to mark the closure of the Space Telescope European Coordination Facility (ST-ECF), based near Munich in Germany, and to celebrate its achievements in supporting Hubble science in Europe over the past 26 years.

    cartwheel
    Release date: 27 December 2010, 10:00

    Lying about 500 million light-years away in the constellation of Sculptor, the cartwheel shape of this galaxy is the result of a violent galactic collision. A smaller galaxy has passed right through a large disc galaxy and produced shock waves that swept up gas and dust — much like the ripples produced when a stone is dropped into a lake — and sparked regions of intense star formation (appearing blue). The outermost ring of the galaxy, which is 1.5 times the size of our Milky Way, marks the shock wave’s leading edge. This object is one of the most dramatic examples of the small class of ring galaxies.

    This image was produced after Hubble data was reprocessed using the free open source software FITS Liberator 3, which was developed at the ST-ECF. Careful use of this widely used state-of-the-art tool on the original Hubble observations of the Cartwheel Galaxy has brought out more detail in the image than ever before.

    Although the ST-ECF is closing, ESA’s mission to bring amazing Hubble discoveries to the public will be unaffected, with Hubblecasts, press and photo releases, and Hubble Pictures of the Week continuing to be regularly posted on spacetelescope.org.”

    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 10:25 am on July 29, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “A spiral galaxy crowned by a star” 

    “Another treasure unearthed from the Hubble archives, this beautiful image shows a spiral galaxy named NGC 4517. Slightly bigger than our Milky Way, it is seen edge-on, crowned by a very bright star. The star is actually much closer to us than the galaxy, explaining why it appears to be so big and bright in the picture.

    gal
    Credit: ESA/Hubble & NASA Acknowledgement: Gilles Chapdelaine
    Release date: 29 July 2013, 10:00

    NGC 4517 is located approximately 40 million light-years away in the constellation of Virgo (The Virgin). It has a bright centre, but this is not visible in this Hubble image. Its orientation has led to it being included in many studies of globular clusters, clumps of stars that orbit the centres of galaxies like satellites.

    The galaxy was discovered in 1784 by William Herschel, who described this region as having “a pretty bright star situated exactly north of the centre of an extended milky ray”. Of course the “milky ray” seen by Herschel is actually this spiral galaxy, but with his 17th century observing gear he could only tell that there a fuzzy, blurry structure below the much brighter star.

    This image is composed from visible and infrared light gathered by NASA/ESA Hubble Space Telescope. A version of this image was entered into the Hubble’s Hidden treasures image processing competition by contestant Gilles Chapdelaine.”

    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 10:40 am on July 19, 2013 Permalink | Reply
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    From NASA/ESA Hubble: “A stranger in the crowd” 

    This article is undated.
    No Writer Credit

    “The constellation of Virgo (The Virgin) is the largest of the Zodiac constellations, and the second largest overall after Hydra (The Water Snake). Its most appealing feature, however, is the sheer number of galaxies that lie within it. In this picture, among a crowd of face- and edge-on spiral, elliptical, and irregular galaxies, lies NGC 4866, a lenticular galaxy situated about 80 million light-years from Earth.

    ngc4886
    NGC4886 Image Credit: European Space Agency
    Release date: 15 July 2013, 10:00

    Lenticular galaxies are somewhere between spirals and ellipticals in terms of shape and properties. From the picture, we can appreciate the bright central bulge of NGC 4886, which contains primarily old stars, but no spiral arms are visible. The galaxy is seen from Earth as almost edge-on, meaning that the disc structure — a feature not present in elliptical galaxies — is clearly visible. Faint dust lanes trace across NGC 4866 in this image, obscuring part of the galaxy’s light.

    To the right of the galaxy is a very bright star that appears to lie within NGC 4886’s halo. However, this star actually lies much closer to us; in front of the galaxy, along our line of sight. These kinds of perspective tricks are common when observing, and can initially deceive astronomers as to the true nature and position of objects such as galaxies, stars, and clusters.

    This sharp image of NGC 4866 was captured by the Advanced Camera for Surveys, an instrument on the NASA/ESA Hubble Space Telescope.”

    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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