Crescent-shaped planetary nebula SH2-188 glows in wisps of green in this skywatching image.
Astrophotographer Bill Snyder captured this stunning deep-space image Feb. 22, 2012 at his Home Observatory in Connellsville Pa.
Sh2-188, also referred to as the Dolphin nebula, is approximately 850 light years from Earth in the constellation Cassiopeia. A light-year is the distance light travels in one year, or about 6 trillion miles (10 trillion kilometers).
The unique, crescent shape of the nebula led astronomers to initially believe SH2-188 was the remnant of a supernova. However, SH2-188 was confirmed to be an asymmetrical planetary nebula.
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.
Follow SPACE.com for the latest in space science and exploration news on Twitter @Spacedotcom and on Facebook.