Multiple exposures are made to collect enough light for an image that would otherwise not be evident to the eye.
Credit: Larry Van Vleet
This stunning image by skywatcher Larry Van Vleet is of Markarian's Chain, a stretch of galaxies in the Virgo cluster.
The galaxies are said to be in a smooth, curved line making them appear to be connected in a chain. Located about 70 million light-years away, the Virgo cluster is a large collection of some 2,000 galaxies that dominate our part of the universe. A light-year is the distance light travels in one year, or about 6 trillion miles (10 trillion kilometers).
In the photo, which Vleet took in April 2009 and recently provided to SPACE.com, the galaxies M84, M86 and M88 are easily visible. The chain was named after B.E. Markarian who first discovered the galaxies move cohesively with each other. The dominant galaxy of the giant cluster is considered to be M87 situated close to the physical center.
The two galaxies close to each other are known as The Eyes, or NGC 4438 and NGC 4435. In the past, these galaxies have come within 16,000 light-years of each other. Gravitational forces from both galaxies tore out material during this close encounter and ripped away gas as well as cosmic dust. Such collisions are fairly common in the crowded Virgo cluster.
Editor's note: If you have an amazing skywatching photo you'd like to share for a possible story or image gallery, please contact managing editor Tariq Malik at firstname.lastname@example.org.