What Is a Supernova?
A supernova is an exploding star that can become billions of times as bright as the sun before gradually fading from view. At its maximum brightness, the exploded star may outshine an entire galaxy. The explosion throws a large cloud of dust and gas into space. The mass of the expelled material may exceed 10 times the mass of the sun.
Astronomers recognize two types of supernovae -- Type I and Type II. Type I supernovae probably occur in...Show More