A neutron star is one type of star that forms after the collapse of a massive star during a supernova. Such stars are composed almost entirely of neutrons, hence the name. A pulsar is a neutron star that emits a beam of electromagnetic radiation. This beam can only be seen when it is pointed towards earth, sort of like the lighthouse effect.
NASA has released a composite image from NASA’s Chandra X-ray Observatory and Spitzer Space Telescope. The image shows the white pulsar in the middle surrounded by dust from the supernova event.
In this image of G54.1+0.3, X-ray data from Chandra are shown in blue, and data from Spitzer in green (a shorter wavelength) and red-yellow (a longer one). The white source near the center of the image is a dense, rapidly rotating neutron star, or pulsar, all that remains of a core-collapse supernova explosion. The pulsar generates a wind of high-energy particles — seen in the Chandra data — that expands into the surrounding environment, illuminating the material ejected in the supernova explosion.
