All stars eventually run out of all there material and gases by slowly burning up all there fuel.
An average
size star like our Sun will bloat in size after a life cycle of 10
billion years and turn into a red giant. Once it is a red giant it will
blow off it's gases and collapse. The collapsed star will eventually
fade and turn into a white dwarf which is the inner core of the star.
After the white dwarf will cool down into a black dwarf which has no
light or heat. It takes so long for a star to cool off into a black
dwarf it is believed that no star has yet reached this stage.
A
red dwarf or smaller mass star will die the same way as an average size
sun like ours, except that it will not turn into a red giant and it
will take billions of years longer to turn into a white and then a black dwarf.
A very large mass star called a blue giant can die similarly to other
smaller stars or it can go super nova. The blue giant gets
even hotter and brighter and turns into a red super giant and then the
star collapses inward and explodes and that is called a super nova.
A supernova is a massive explosion of star dust and gases from when the
star explodes. The photos scientists have of supernovae are actually of
when the super nova happened millions or billions of years ago because
it takes light so long to travel here from that far away. When the
scientists see these super novae it is like seeing into the past. Super
nova are very bright and colorful and among the powerful events in the
universe. Did you know that after a star dies and goes super nova the
dust will help make new stars in the future.
A neutron star is the only thing left of the old star.
Another
possibility is that it can also turn into something called a black hole
which nothing can escape not even light. Light travels at 186,000 miles
or 300,000 kilometers per second and it still cannot even escape, that
is why a black hole looks black, because no light that goes in comes
out. No person has ever seen a black hole. A black hole sucks up
matter. At the Event Horizon the gravity is so strong that nothing can
escape, it's the point of no return. Did you know that in a smaller
black hole by the time you got to the Event horizon you would be
stretched skinny like spaghetti and then get ripped apart by
gravity pulling outward and inward. In a larger black hole it would
seem more inviting because you would not get ripped apart, but it is
not. You would last a little longer but you would get sucked in and get
to an area that is burning hot and you would die. This is what
scientists believe but don't worry it's impossible for a human to get
that close to a black hole anyway and our Sun is not big enough to ever
turn into a black hole.
Did you know that the biggest black holes are believed to be at the
center of galaxies? They are called super massive black holes and
scientists believe there is one at the center of our galaxy, The Milky
Way. There is a theory that galaxies need a black hole in order to be
made. Astronomers used to believe that there were all these gases that
created the galaxies but they didn't know how the stars were created.
Now they believe that the gases collapse inward creating a super
massive black hole at the center of what will become a galaxy.
When the gases rubbed against each other really fast when they were orbiting the black hole they heated up and turned into stars, creating
galaxies.
I drew this picture of a supernova on
the computer.
