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Double asteroid belt in Solar System clone

...Spitzer observations have discerned two rocky asteroid belts and an icy outer ring surrounding our Sun’s doppelgänger Epsilon Eridani that could have been shaped by evolving planets..

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Fireball captured by Canadian cameras

...for the second time this year The University of Western Ontario’s Meteor Group has captured rare footage of a meteor streaking across the sky and possibly falling to the ground...

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ESA gravity mission slips to 2009

...the launch of Europe’s Gravity field and steady-state Ocean Circulation Explorer (GOCE) has slipped to February 2009 due to ongoing technical faults with its launcher..

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Video archive

STS-120 day 2 highlights

Flight Day 2 of Discovery's mission focused on heat shield inspections. This movie shows the day's highlights.

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STS-120 day 1 highlights

The highlights from shuttle Discovery's launch day are packaged into this movie.

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STS-118: Highlights

The STS-118 crew, including Barbara Morgan, narrates its mission highlights film and answers questions in this post-flight presentation.

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 Mission film

STS-120: Rollout to pad

Space shuttle Discovery rolls out of the Vehicle Assembly Building and travels to launch pad 39A for its STS-120 mission.

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Dawn leaves Earth

NASA's Dawn space probe launches aboard a Delta 2-Heavy rocket from Cape Canaveral to explore two worlds in the asteroid belt.

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Dawn: Launch preview

These briefings preview the launch and science objectives of NASA's Dawn asteroid orbiter.

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ESO produces deepest UV image of the Universe
BY DR EMILY BALDWIN
ASTRONOMY NOW

Posted: 07 November, 2008

A new image from the European Southern Observatory (ESO) offers the deepest ground-based ultraviolet image of the Universe ever obtained.

The image contains more than 27 million pixels and reveals a cocktail of brightly coloured and varying shaped galaxies that make up the Chandra Deep Field South (CDF-S). The CDF-S is one of two regions selected as part of the Great Observatories Origins Deep Survey (GOODS), an effort of the worldwide astronomical community that unites the deepest observations from ground- and space-based facilities at all wavelengths from X-ray to radio. Its primary purpose is to provide astronomers with the most sensitive census of the distant Universe to assist in the fundamental study of the formation and evolution of galaxies.

The Chandra Deep Field South observed with ESO’s VIMOS and WFI instruments is the deepest image every taken in the U-band. The image covers a region 14.1 x 21.6 arcminutes. Image: ESO/ Mario Nonino, Piero Rosati and the ESO GOODS Team.

The image combines data obtained from 55 hours of observations with the VIMOS (Visible wide field Imager and Multi-Object Spectrograph) instrument on ESO’s Very Large Telescope (VLT) in the U- and R-bands, as well as data obtained in the B-band with the Wide-Field Imager (WFI) attached to the 2.2 metre Max Planck Gesellschaft/ESO telescope at La Silla. The U-band represents the boundary between visible and ultraviolet light, and in this image is the result of 40 hours of staring at the same region of the sky, resulting in the deepest image ever taken from the ground at this wavelength. At these depths, the sky is almost completely covered by galaxies, each one like our own Milky Way Galaxy, hosting hundreds of billions of stars.

Only a very few stars in this image actually belong to the Milky Way, though, and one can be seen to the left of the second brightest star towards the top of the field of view. It appears as a slightly elongated rainbow because the star moved while the data were being acquired in the different filters over several years.

Such a deep image unveils galaxies a billion times fainter than the unaided eye can see and over a range of colours not directly
observable by the human eye. The CDF-S has already been essential to the discovery of a large number of new galaxies that are so far away that they are seen as they were when the Universe was a youthful two billion years old.