Explanation:
What could cause a bang this big?
This
supernova explosion
was so inherently bright that it could be seen nearly 5 billion
light years away (a
redshift
of 0.28) even with a small telescope.
Specific colors emitted during
SN 2005ap
indicate that it was a
Type II supernova,
a breed of stellar explosion that results when a high mass star begins
fusing
heavy elements in or near its core.
Type II supernovas may be more powerful than their
Type Ia cousins,
but they are not currently more useful cosmologically because
astronomers don't understand how to accurately recover their
intrinsic brightnesses.
It is therefore dimmer
Type Ia supernovas
that are used by astronomers to calibrate the
distance scale
of the nearby universe.
Were Type II supernova
better understood, astronomers might be able to
probe distances
further into the universe, and so probe the stability of the strange
dark energy that dominates the present universe.
Pictured above
in a digitally compressed image, the bright supernova SN 2005ap is
visible on the right where no exploding star had been seen on the
left less than three months before.
