Click on the image above to see an animation of an exploding star producing a gamma-ray burst.
Long Gamma-Ray Bursts (GRBs) are those bursts that last longer than two seconds.
Unlike the short GRBs which can occur in any type of galaxy, long GRBs have only been observed to take place in spiral galaxies. This is
an important observation because spiral galaxies are the only galaxies that keep forming new generations of stars.
Astronomers believe those long GRBs are generated when a massive star explodes in a kind of supernova explosion. The only stars that explode
like this are the most massive stars which do not live long compared to other stars.
Short GRBs are thought to occur for a completely different reason. Click on the button to learn about short GRBs or another topic.
