Image of the Day - Crab Nebula

Today's Image of the Day for 30/9/11 - Crab Nebula

Crab Nebula courtesy of eso.org

The Crab Nebula is a supernova remnant and pulsar wind nebula in the constellation of Taurus. The nebula was observed by John Bevis in 1731; it corresponds to a bright supernova recorded by Chinese and Arab astronomers in 1054. Located at a distance of about 6,500 light-years from Earth, the nebula has a diameter of 11 light-years and expands at a rate of about 1,500 kilometers per second. It is part of the Perseus Arm of the Milky Way Galaxy. At the center of the nebula lies the Crab Pulsar, a neutron star (or spinning ball of neutrons), 28–30 km across, which emits pulses of radiation from gamma rays to radio waves with a spin rate of 30.2 times per second.

Image of the Day - Keyhole Nebula

Today's Image of the Day for 29/9/11 - Keyhole Nebula

Keyhole Nebula courtesy of WallpaperCavern

Located around 8000 light years away in the Carina Nebula this portion is known as the Keyhole Nebula, a name given to it by John Herschel in the 19th century. The Keyhole Nebula is actually a much smaller and darker cloud of cold molecules and dust, containing bright filaments of hot, fluorescing gas, silhouetted against the much brighter background nebula. The diameter of the Keyhole structure is approximately 7 light years.