December 5, 2015

Supernova Remnant W44

Supernova Remnant W44Supernova Remnant W44 infraredSupernova Remnant W44 x-ray

Also known as G34.7-0.4, W44 is an expanding supernova remnant that is interacting with dense interstellar material that surrounds it. X-rays from Chandra (blue) show that hot gas fills the shell of the supernova remnant as it moves outward. Infrared observations from the Spitzer Space Telescope reveal the shell of the supernova remnant (green) as well as the molecular cloud (red) into which the supernova remnant is moving and the stars in the field of view. 

Image Credit: X-ray: NASA/CXC/Univ. of Georgia/R.Shelton & NASA/CXC/GSFC/R.Petre; Infrared: NASA/JPL-Caltech
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December 4, 2015

Cheshire Cat: The SDSS J103842.59+484917.7 Galaxy Group

Cheshire Cat Galaxy Group
Cheshire Cat Galaxy Group opticalCheshire Cat Galaxy GroupCheshire Cat Galaxy Group x-ray

What is it?
A group of galaxies nicknamed the "Cheshire Cat" about 4.6 billion light years from Earth.

How Far Away is it?
About 4.6 billion light years.

How is it Made?
X-rays from the Chandra, optical data from Hubble telescope.

How Big is it?
About 1.45 million light years across.

What do the Colors Mean?
X-rays are blue, optical red, green and blue.

Where is it Located?
In the constellation Ursa Major.

  • This group of galaxies has been nicknamed the "Cheshire Cat" because of its resemblance to a smiling feline.
  • Some of the cat-like features are actually distant galaxies whose light has been stretched and bent by the large amounts of mass contained in foreground galaxies.
  • X-rays from Chandra show that the two "eye" galaxies and the smaller galaxies associated with them are slamming into one another in a giant galactic collision.

Astronomers think that in the future the "Cheshire Cat" group will become what is known as a fossil group, a gathering of galaxies that contains one giant elliptical galaxy and other much smaller, fainter ones. Today, researchers know each "eye" galaxy is the brightest member of its own group of galaxies and these two groups are racing toward one another at over 300,000 miles per hour. Data from Chandra (purple), which has been combined with optical data from Hubble, show hot gas that has been heated to millions of degrees, which is evidence that the galaxy groups are slamming into one another. Chandra's X-ray data also reveal that the left "eye" of the Cheshire Cat group contains an actively feeding supermassive black hole at the center of the galaxy. 

Image Credit: X-ray: NASA/CXC/UA/J.Irwin et al; Optical: NASA/STScI)
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December 1, 2015

The star forming cloud RCW 34

star forming cloud RCW 34

This richly coloured cloud of gas called RCW 34 is a site of star formation in the southern constellation of Vela (The Sails). This image was taken using the FORS instrument on ESO’s Very Large Telescope in northern Chile.

Image Credit: ESO
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November 29, 2015

Artist’s impression of CR7: the brightest galaxy in the early Universe

brightest galaxy

This artist’s impression shows CR7 a very distant galaxy discovered using ESO’s Very Large Telescope. It is by far the brightest galaxy yet found in the early Universe and there is strong evidence that examples of the first generation of stars lurk within it. These massive, brilliant, and previously purely theoretical objects were the creators of the first heavy elements in history — the elements necessary to forge the stars around us today, the planets that orbit them, and life as we know it. This newly found galaxy is three times brighter than the brightest distant galaxy known up to now.

Image Credit: ESO/M. Kornmesser
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