The halo of galaxy Messier 87The giant elliptical galaxy Messier 87 is surrounded by a huge halo. An increase in brightness in the top-right part of this halo and the motion of planetary nebulae in the galaxy are the last remaining signs of a medium-sized galaxy that collided with M87.

This wide field image also contains many other galaxies forming the Virgo Cluster, of which Messier 87 is the largest member. The two galaxies at the edge of the top right of the frame are nicknamed “the Eyes.”

Image Credit: ESO

Billions and Billions

Over 200 billion. Stars that is. This fuzzy blob of light is the galaxy known as Messier 49 (or M49). It’s a giant elliptical galaxy with 200 billion stars. Spiral galaxies have a well-defined structure with spiral arms, but elliptical galaxies are fairly smooth and lack obvious features. M49 was the first member of the Virgo Cluster of galaxies to be discovered, and it is more luminous than any other galaxy at its distance (56 million light-years) or nearer. It is about 157,000 light-years across.

Image Credit: NASA / ESA