« EcoAlert: World's Newest Nation to Emerge as Wildlife EcoTourism Hotspot | Main | The "Rare Earth" Debate: Are We the Sole Intelligent Life in the Milky Way? »
July 11, 2011
Image of the Day: "Hoag's Object" --A Mysterious Ring Galaxy
The mystery is: Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag discovered this odd extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older. Between the two is a gap that appears almost completely dark. How the object formed remains unknown. Possibilities include a galaxy collision billions of years ago and the gravitational affect of a central bar that has since vanished. Hoag's Object spans about 100,000 light years and lies about 600 million light years away toward the constellation of the Snake (Serpens). Coincidentally, visible in the gap (at about one o'clock) is yet another ring galaxy that likely lies far in the distance. Fascinating!
Image Credit: R. Lucas (STScI/AURA), Hubble Heritage Team, NASA
Comments
How Hoag's Object formed remains unknown, although similar objects have been identified and collectively labeled as a form of ring galaxy. Genesis hypotheses include a galaxy collision billions of years ago and the gravitational effect of a central bar that has since vanished.
Posted by: PetCareRx | July 11, 2011 at 12:54 AM
« EcoAlert: World's Newest Nation to Emerge as Wildlife EcoTourism Hotspot | Main | The "Rare Earth" Debate: Are We the Sole Intelligent Life in the Milky Way? »
Monday, 11 July 2011
Image of the Day: "Hoag's Object" --A Mysterious Ring Galaxy
via dailygalaxy.com
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment