Star Streams of the Splinter Galaxy

Spectacular tidal streams of stars surround galaxy NGC 5907, extending more than 150,000 light-years from the narrow, edge-on spiral, also known as the Splinter or Knife Edge Galaxy. The streams are believed to represent the ghostly trail of a dwarf galaxy -- debris left along the orbit of a smaller satellite galaxy that was gradually torn apart and merged with NGC 5907 over four billion years ago.

This remarkable image was made from a small robotic observatory in New Mexico, supporting cosmological scenario in which large spiral galaxies, including our own Milky Way, were formed by absorbing smaller ones. NGC 5907 lies about 40 million light-years distant in the northern constellation Draco.

http://apod.nasa.gov/apod/ap080619.html