While they
might only seem like galactic fireworks, supernovas do a lot more than just generate
pretty pictures like this one.
All the
elements heavier than oxygen were created by supernovae billions of years ago. When
stars burst, they spew out these heavy elements into space, enriching molecular
clouds that are the sites of star birth. If not for supernovae, the calcium in
our bones or iron in our blood probably wouldn’t exist.
There are
two ways that supernova can occur. In one, a white dwarf star accumulates
material from a companion star and eventually reaches critical mass. When this
happens, a thermonuclear explosion occurs.
In the second,
a giant star runs out of nuclear fuel and the outer layers of the star rapidly
collapse inwards because of the star’s own gravity. As the layers collapse on
the iron core, they bounce back outwards, ripping apart the star.
The above
image from the Whirlpool Galazy (M51) appears to be
an example of this second type of supernova. It was first reported on June 28
and photographed on June 30. Since then, astronomers believe they have
identified the star that produced the supernova. It is rare to find the
progenitor stars and this identification will help astronomer learn more about
these events.
