Stories tagged Crab Nebula


Astronomers at the University of Minnesota studying the Crab Nebula with the Spitzer Space Telescope have found that a type of dust has gone missing from the nebula.

A nebula is a cloud of dust and gas in space which can be, depending on the type of nebula, the birthplace of stars. The Crab Nebula formed after a star went supernova (exploded), and hurled remnants of itself into space (called supernova remnants). Within the nebula molecular clouds collapse and fragment under their own gravity forming new stars.

The team at the University of Minnesota was looking for very small cosmic dust in the Crab Nebula. This small cosmic dust is composed of very small solid particles in space, except ice. This fine cosmic dust was observed to form in supernova remnants of a star only a few years after the star exploded (Supernova 1987A) so the astronomers at the University of Minnesota expected to find the cosmic dust in the Crab Nebula. What they found, using the Spitzer Space Telescope, was that the dust present in the Crab Nebula, while still very small, was 10 to 100 times larger than the small particles they expected to find.

So, where did the finer dust go? One idea is that the pulsar at the center of the Crab Nebula, which spins at a rate of 30 times a second, is sending out ultraviolet radiation as well as protons and electrons at close to the speed of light, which could be destroying the smaller dust particles.