APOD 3.5

Simeis 147: Supernova Remnant

(2011 February 12)

This picture shows the supernova remnant Simeis 147, also cataloged as Sh2-240. It is near the constellation Taurus and it is huge. It covers almost 3 degrees in the sky which is the equivalent of 6 full moons. It is 3,000 light-years long and 150 light-years wide. This picture is a composite and it had image data taken through narrow band filters to highlight emission from hydrogen and oxygen atoms tracing regions of shocked, glowing gas. It is estimated to be about 40,000 years old and what was also left behind is a spinning neutron star or pulsar. This is all that remains of the star's core after the explosion.

Supernovas are one of the most violent events in the universe. The force of the explosion creates a blinding flash of radiation and shock waves comparable to sonic booms. Supernovas are classified by their optical properties. Massive stars spend their lives burning nuclear fuel and nuclei of light elements like hydrogen and helium are combined to make heavier elements like carbon and oxygen in a progression which ends with iron. When a supernova explosion occurs, the explosion blasts these heavier elements back into space. The elements and hot temperature creates the color we see here.