Star-birth party almost over in NGC 2976: NGC 2976 does not look like a typical spiral galaxy, as this  NASA/ESA Hubble Space Telescope image shows. In this view of the oddball galaxy's inner region, there are no obvious spiral arms. Dusty filaments running through the disc show no clear spiral structure. A raucous interaction with a neighbouring group of hefty galaxies stripped away some gas and funneled the rest to the galaxy's inner region, fueling star birth about 500 million years ago. At the same time, the galaxy's outer regions stopped making stars because the gas ran out. Now, the inner disc is almost out of gas as new stars burst to life, shrinking the star-formation region to a small area of about 5,000 light-years around the core. Astronomers pieced together the galaxy's star-formation story with the help of Hubble's sharp vision. The galaxy's relatively close distance to Earth allowed Hubble's Advanced Camera for Surveys (ACS) to resolve hundreds of thousands of individual stars. What look like grains of sand in the image are actually single stars. Studying the individual stars allowed astronomers to determine their colour and brightness, which provided information about when they formed. Based on this analysis, the astronomers reconstructed the star-making history for large areas of the galaxy. The blue dots in the image are fledgling blue giant stars residing in the remaining active star-birth regions. NGC 2976 resides on the fringe of the M81 group of galaxies, located about 12 million light-years away in the constellation Ursa Major. The observation is part of the ACS Nearby Galaxy Survey Treasury (ANGST) program. Data for the image were taken from 27 December 2006 to 10 January 2007.

Name: NGC 2976
Type: Local Universe : Galaxy : Type : Spiral
Category: Galaxies
Constellation: Ursa Major
Distance: 12 million light years
Release date: 14 January 2010, 15:00
Credit: NASA, ESA, and J. Dalcanton and B. Williams (University  of Washington, Seattle)

Comet-like asteroid P/2010 A2: The comet-like asteroid P/2010 A2.

Name: P/2010 A2 (LINEAR)
Type: Solar System : Interplanetary Body : Asteroid
Category: Solar System
Release date: 2 February 2010, 16:00
Credit: NASA, ESA and D. Jewitt (UCLA)

Close-up of comet-like asteroid P/2010 A2: Close-up of comet-like asteroid P/2010 A2.

Name: P/2010 A2 (LINEAR)
Type: Solar System : Interplanetary Body : Asteroid
Category: Solar System
Release date: 2 February 2010, 16:00
Credit: NASA, ESA and D. Jewitt (UCLA)

Hickson Compact Group 31: interacting galaxies glow with millions of young stars: These four dwarf galaxies waited billions of years to come together, setting off a fireworks show as thousands of new star clusters come to life. The distorted galaxies are quickly producing massive, hot, young stars that are pumping out ultraviolet radiation, heating up surrounding gas clouds, and causing them to glow. Such encounters between dwarf galaxies are normally seen billions of light-years away and therefore occurred billions of years ago. But these galaxies, members of Hickson Compact Group 31, are relatively nearby, only 166 million light-years away. In this composite image of the galaxy grouping, the bright, distorted object at middle, left, is actually two colliding dwarf galaxies. Myriad star clusters have formed in the streamers of debris pulled from the galaxies and at the site of their head-on collision. The cigar-shaped object above the galaxy duo is another member of the group. A bridge of star clusters connects the trio. A long rope of bright star clusters points to the fourth member of the group, at lower right. The bright object in the center is a foreground star. The image was composed from observations made by the Hubble Space Telescope's Advanced Camera for Surveys, NASA's Spitzer Space Telescope, and the Galaxy Evolution Explorer (GALEX). Astronomers used Hubble's Advanced Camera for Surveys to resolve the youngest and brightest of star clusters, which allowed them to calculate the clusters' ages, map the star-formation history, and determine that the galaxies are starting the final stages of galaxy assembly. Hubble reveals that the brightest clusters, hefty groups each holding at least 100,000 stars, are less than 10 million years old. Astronomers say the interacting galaxies will form a large elliptical galaxy in another billion years. The Advanced Camera for Surveys data were taken on 8 August 2006. The principal investigator was Jane Charlton of Pennsylvania State University, University Park (USA). The Spitzer observations were made on 22 February 2005. The principal investigator was Kelsey Johnson of the University of Virginia and the National Radio Astronomy Observatory, both in Charlottesville (USA). The GALEX data were taken on 27 December 2004.

Name: HCG 31, Hickson Compact Group 31
Type: Local Universe : Galaxy : Grouping : Cluster
Category: Galaxies
Constellation: Eridanus
Distance: 180 million light years
Release date: 18 February 2010, 15:00
Credit: NASA, ESA, S. Gallagher (The University of Western Ontario) and J. English (University of Manitoba)

Hubble's view of Hickson Compact Group 31: These four dwarf galaxies waited billions of years to come together, setting off a fireworks show as thousands of new star clusters come to life. The distorted galaxies are quickly producing massive, hot, young stars that are pumping out ultraviolet radiation, heating up surrounding gas clouds, and causing them to glow. Such encounters between dwarf galaxies are normally seen billions of light-years away and therefore occurred billions of years ago. But these galaxies, members of Hickson Compact Group 31, are relatively nearby, only 166 million light-years away. In this image, taken by the NASA/ESA Hubble Space Telescope, the bright, distorted object at middle, left, is actually two colliding dwarf galaxies. Myriad star clusters have formed in the streamers of debris pulled from the galaxies and at the site of their head-on collision. The cigar-shaped object above the galaxy duo is another member of the group. A bridge of star clusters connects the trio. A long rope of bright star clusters points to the fourth member of the group, at lower right. The bright object in the center is a foreground star. Astronomers used Hubble's Advanced Camera for Surveys to resolve the youngest and brightest of star clusters, which allowed them to calculate the clusters' ages, map the star-formation history, and determine that the galaxies are starting the final stages of galaxy assembly. Hubble reveals that the brightest clusters, hefty groups each holding at least 100,000 stars, are less than 10 million years old. Astronomers say the interacting galaxies will form a large elliptical galaxy in another billion years. The Advanced Camera for Surveys data were taken on 8 August 2006. The principal investigator was Jane Charlton of Pennsylvania State University, University Park (USA).

Name: HCG 31, Hickson Compact Group 31
Type: Local Universe : Galaxy : Grouping : Cluster
Category: Galaxies
Constellation: Eridanus
Distance: 180 million light years
Release date: 18 February 2010, 15:00
Credit: NASA, ESA, J. English (University of Manitoba) and the Hubble Heritage Team (STScI/AURA). Acknowledgment: S. Gallagher (The University of Western Ontario)