Galaxy Triplet Arp 274

To celebrate the 100 Hours of Astronomy, the people working on the Hubble Space Telescope decided to let the public decide of what the telescope will take a picture. This vote, called Hubble's Next Discovery - You Decide, closed on March 1, and consisted of six interesting objects, details about which are not completely understood. I personally voted for the winner, Arp 274, since it seemed to be a pair of interacting galaxies. However, these galaxies have now revealed a surprise.

Arp 274 was previously thought to be a set of interacting galaxies, galaxies that are "colliding" and gravitationally affecting one another. The ground-based image (left) of the same area of the sky certainly makes it seem that way. But, the new image by the Hubble, with far more detail, reveals that the three galaxies may just be galaxies located near each other, but not interacting together. The largest galaxy in the center, a barred spiral galaxy, appears to be extending an arm into the other spiral galaxy, on the right. Distortion of the shapes of the galaxies by gravity would indicate interaction, but this is simply not exhibited by these galaxies. Additionally, there is a third galaxy in the area, a small compact galaxy. All three contain bright blue areas, where star formation takes place.

You can get this image at the news release, or download a wallpaper for your computer at HubbleSite.

Update: Here is a video detailing the process used to generate this image.



Images: NASA, Palomar Observatory

Astronomy and Space celebrates International Year of Astronomy 2009.