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Hubble goes extreme

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Hubble Goes to the eXtreme to Assemble Farthest-Ever View of the Universe

09.25.12

Like photographers assembling a portfolio of best shots, astronomers have assembled a new, improved portrait of mankind's deepest-ever view of the universe.

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(Credit: NASA; ESA; G. Illingworth, D. Magee, and P. Oesch, University of California, Santa Cruz; R. Bouwens, Leiden University; and the HUDF09 Team)

› Larger image | 13 MB tif

Called the eXtreme Deep Field, or XDF, the photo was assembled by combining 10 years of NASA Hubble Space Telescope photographs taken of a patch of sky at the center of the original Hubble Ultra Deep Field. The XDF is a small fraction of the angular diameter of the full moon.

The Hubble Ultra Deep Field is an image of a small area of space in the constellation Fornax, created using Hubble Space Telescope data from 2003 and 2004. By collecting faint light over many hours of observation, it revealed thousands of galaxies, both nearby and very distant, making it the deepest image of the universe ever taken at that time.

The new full-color XDF image is even more sensitive, and contains about 5,500 galaxies even within its smaller field of view. The faintest galaxies are one ten-billionth the brightness of what the human eye can see.

This video zooms into the small areas of sky that the Hubble Space Telescope was aimed at to construct the eXtreme Deep Field, or XDF. The region is located in the southern sky, far away from the glare of the Milky Way, the bright plane of our galaxy. In terms of angular size, the field is a fraction the angular diameter of the full moon, yet it contains thousands of galaxies stretching back across time. (Credit: NASA; ESA; and G. Bacon and Z. Levay, STScI)

› Download video (13 MB mp4)

Magnificent spiral galaxies similar in shape to our Milky Way and the neighboring Andromeda galaxy appear in this image, as do the large, fuzzy red galaxies where the formation of new stars has ceased. These red galaxies are the remnants of dramatic collisions between galaxies and are in their declining years. Peppered across the field are tiny, faint, more distant galaxies that were like the seedlings from which today's magnificent galaxies grew. The history of galaxies -- from soon after the first galaxies were born to the great galaxies of today, like our Milky Way -- is laid out in this one remarkable image.

Hubble pointed at a tiny patch of southern sky in repeat visits (made over the past decade) for a total of 50 days, with a total exposure time of 2 million seconds. More than 2,000 images of the same field were taken with Hubble's two premier cameras: the Advanced Camera for Surveys and the Wide Field Camera 3, which extends Hubble's vision into near-infrared light.

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This illustration compares the angular size of the XDF field to the angular size of the full moon. A finger held at arm's length would appear to be about twice the width of the moon in this image. Note that this illustration does not show the actual observation of the XDF relative to the location of the moon. (Illustration Credit: NASA; ESA; and Z. Levay, STScI; Moon Image Credit: T. Rector; I. Dell'Antonio/NOAO/AURA/NSF)

› Larger image

"The XDF is the deepest image of the sky ever obtained and reveals the faintest and most distant galaxies ever seen. XDF allows us to explore further back in time than ever before", said Garth Illingworth of the University of California at Santa Cruz, principal investigator of the Hubble Ultra Deep Field 2009 (HUDF09) program.

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This image from 2009 shows an updated version of the Hubble Ultra Deep Field. The new eXtreme Deep Field could be considered a more detailed view of a portion of this image. (Credit: NASA; ESA; G. Illingworth, UCO/Lick Observatory and the University of California, Santa Cruz; R. Bouwens, UCO/Lick Observatory and Leiden University; and the HUDF09 Team)

› Larger image

› More info from HubbleSite.org

The universe is 13.7 billion years old, and the XDF reveals galaxies that span back 13.2 billion years in time. Most of the galaxies in the XDF are seen when they were young, small, and growing, often violently as they collided and merged together. The early universe was a time of dramatic birth for galaxies containing brilliant blue stars extraordinarily brighter than our sun. The light from those past events is just arriving at Earth now, and so the XDF is a "time tunnel into the distant past." The youngest galaxy found in the XDF existed just 450 million years after the universe's birth in the big bang.

Before Hubble was launched in 1990, astronomers could barely see normal galaxies to 7 billion light-years away, about halfway across the universe. Observations with telescopes on the ground were not able to establish how galaxies formed and evolved in the early universe.

Hubble gave astronomers their first view of the actual forms and shapes of galaxies when they were young. This provided compelling, direct visual evidence that the universe is truly changing as it ages. Like watching individual frames of a motion picture, the Hubble deep surveys reveal the emergence of structure in the infant universe and the subsequent dynamic stages of galaxy evolution.

The infrared vision of NASA's planned James Webb Space Telescope will be aimed at the XDF. The Webb telescope will find even fainter galaxies that existed when the universe was just a few hundred million years old. Because of the expansion of the universe, light from the distant past is stretched into longer, infrared wavelengths. The Webb telescope's infrared vision is ideally suited to push the XDF even deeper, into a time when the first stars and galaxies formed and filled the early "dark ages" of the universe with light.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Md., manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Md., conducts Hubble science operations. STScI is operated by the Association of Universities for Research in Astronomy, Inc., in Washington.

look what happens when human being's co-operate :)

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hs-2012-38-b-web_print.jpgSeptember 6, 2012: Two very different galaxies drift through space together in this image taken by NASA's Hubble Space Telescope. The peculiar galaxy pair is called Arp 116. Arp 116 is composed of a giant elliptical galaxy known as Messier 60 (or M60) and a much smaller spiral galaxy, NGC 4647. The faint bluish spiral galaxy NGC 4647 is about two-thirds of M60 in size and much lower in mass — roughly the size of our galaxy, the Milky Way.

M60 lies roughly 54 million light-years away from Earth; NGC 4647 is about 63 million light-years away. This image combines exposures from Hubble's Advanced Camera for Surveys and Wide Field and Planetary Camera 2

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NASA Telescopes Spy Ultra-Distant Galaxy Amidst Cosmic 'Dark Ages'

September 19, 2012: With the combined power of NASA's Spitzer and Hubble space telescopes, as well as a cosmic magnification effect, astronomers have spotted what could be the most distant galaxy ever seen. Light from the young galaxy captured by the orbiting observatories first shone when our 13.7-billion-year-old universe was just 500 million years old. The far-off galaxy existed within an important era when the universe began to transit from the so-called cosmic dark ages. During this period, the universe went from a dark, starless expanse to a recognizable cosmos full of galaxies. The discovery of the faint, small galaxy opens a window onto the deepest, remotest epochs of cosmic history.

In the big image at left, the many galaxies of the massive cluster MACS J1149+2223 dominate the scene. Gravitational lensing by the giant cluster brightened the light from the newfound galaxy, known as MACS1149-JD, some 15 times. At upper right, a partial zoom-in shows MACS1149-JD in more detail, and a deeper zoom appears to the lower right

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Is this the most distant object we have ever discovered?

avt-small.jpgGeorge Dvorsky

medium.jpg Astronomers working with NASA's Spitzer and Hubble space telescopes have detected what they believe to be the most distant object ever discovered — a tiny galaxy residing 13.2 billion light years away. Given that the universe was only 500 million years old at the time, this galaxy must have been among the very first star clusters to have emerged — a new phase of cosmological events that pulled the universe out of its primordial darkness. {C}

To make the discovery, the astronomers used more than just telescopes — they also used a convenient interstellar magnification effect called gravitational lensing. Predicted by Einstein, this phenomenon occurs when the gravity of foreground objects warps and magnifies the light from background objects. In this case, the far-away galaxy was magnified by a factor of 15, allowing the astronomers to catch a glimpse. The astronomers' accomplishment was made all the more amazing when considering that the galaxy is only 1% of the mass of the Milky Way.

medium.jpg That's incredible. Astronomers have detected a small and compact object that's only 1/100th the mass of our own galaxy — and at a distance of 13.2 billion light years! Imagine what we'll discover when the next generation of space-based telescopes are finally up-and-running.

And the science backing this claim is on solid ground. A team of astronomers led by Wei Zheng of The Johns Hopkins University detected the galaxy across five different wavebands. Normally, distant galaxies are glimpsed in a single color, but by using the Cluster Lensing and Supernova Survey with Hubble program (CLASH), the Hubble Space Telescope detected the galaxy in four wavelength bands. Spitzer's Infrared Array Camera (IRAC) confirmed the fifth band.

The light from this galaxy started its epic journey to Earth back when the universe was just 3.6% of its present age. Astronomers believe that this galaxy would have been one of many to have emerged around this time as stars started to form and coalesce for the very first time. In a way, it's a precursor to more "modern" galaxies that have had the time to merge with larger clusters of stars. In a sense, it's a glimpse of what the universe must have looked like when it was only 500 million years old.

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Hubble Sees Cosmic Riches

ScienceDaily (Oct. 5, 2012) — A dazzling new image shows the globular cluster Messier 69, or M 69 for short, as viewed through the NASA/ESA Hubble Space Telescope. Globular clusters are dense collections of old stars. In this picture, foreground stars look big and golden when set against the backdrop of the thousands of white, silvery stars that make up M 69.

[url=http://www.sciencedaily.com/releases/2012/10/121005134454.htm#]

Another aspect of M 69 lends itself to the bejeweled metaphor: As globular clusters go, M 69 is one of the most metal-rich on record. In astronomy, the term "metal" has a specialized meaning: it refers to any element heavier than the two most common elements in our Universe, hydrogen and helium. The nuclear fusion that powers stars created all of the metallic elements in nature, from the calcium in our bones to the carbon in diamonds. Successive generations of stars have built up the metallic abundances we see today.

Because the stars in globular clusters are ancient, their metallic abundances are much lower than more recently formed stars, such as the Sun. Studying the makeup of stars in globular clusters like M 69 has helped astronomers trace back the evolution of the cosmos.

M 69 is located 29 700 light-years away in the constellation Sagittarius (the Archer). The famed French comet hunter Charles Messier added M 69 to his catalogue in 1780. It is also known as NGC 6637.

The image is a combination of exposures taken in visible and near-infrared light by Hubble's Advanced Camera for Surveys, and covers a field of view of approximately 3.4 by 3.4 arcminutes.

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Early galaxies full of cosmic dust

Tuesday, 16 October 2012 Stuart Gary

ABC

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Dust has been for more than 13 billion years according to a new study (Source: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)-ESA/Hubble Collaboration)

Space dust Astronomers have found dusty giant galaxies were already in existence 13 billion years ago, far earlier than previously thought.

The discovery reported in the Astrophysical Journal, means planets, which are made from coalescing dust particles, may also have already formed that far back in time.

The study's lead author Assistant Professor Steven Finkelstein from the University of Texas, says the discovery came as a complete surprise.

"I don't think we really expected that," says Finkelstein.

"We thought that 13 billion years ago would have been so early in the universe, that dust really didn't have a chance to form."

"But we now know that's simply not the case, at least in the most massive galaxies."

Using NASA's Hubble Space Telescope, Finkelstein and colleagues found that on average, galaxies appear less dusty the further back in time they look.

"If you go far enough back, dust doesn't exist in galaxies," says Finkelstein.

"That's what you would expect, because only hydrogen and helium were made in the big bang, and dust is made up of heavier elements like carbon, silicon and magnesium produced by the first generations of stars."

Size matters

Finkelstein hypothesises why dust is only found in these early massive galaxies.

"Galaxies have large outflows of gas and dust from their interstellar medium, and it's a lot easier for that outflow to occur in low mass galaxies, where there's less gravity," says Finkelstein.

"Dust may be forming in all early epoch galaxies, but it's only sticking around in big galaxies because they have enough mass to hang on to their dust."

The findings are based on data from CANDELS, the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey, a huge two-month study carried out by the Hubble Space Telescope.

Finkelstein and colleagues examined the colour of galaxies in the Hubble images to see how red they look.

"Dust makes things appear red, so the redder a galaxy looks, the more dust it has," says Finkelstein.

"As well as being important for planet formation, the dust also blocks out some of the light, making it more difficult to determine how luminous a galaxy is, and consequently how much star formation is taking place in it."

More surveys

Finkelstein and colleagues have more work to do, including taking spectroscopy of these galaxies to work out what they're made of.

"We can do some of that now with today's ten-metre telescopes," says Finkelstein.

"But we're really waiting for the next generation of big telescopes, such as the 25-metre Giant Magellan Telescope, and the space-based James Webb Telescope which will let us look even farther back in space-time to see what's there."

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