NASA’s Wide-field Infrared Survey Explorer (WISE) recently captured this image of Puppis A, a supernova remnant roughly 10 light-years in diameter and about 7,000 light years from Earth.
The red, rose-like cloud represents the infrared signature of dust and gas heated by the expanding shock wave from the supernova explosion. Appearing green is the cooler infrared signature of the much older Vela Supernova Remnant, four times closer to Earth than Puppis A.
At the center of Puppis A is a hypervelocity neutron star too small to be seen in the image. Inexplicably traveling at an estimated 5 million km/hr (3 million mi/hr), the star has been nicknamed the “Cosmic Cannonball.”
The Puppis A supernova explosion would have been visible on Earth about 3,700 years ago, and remains one of the brightest sources in the x-ray sky.