Stellar
Evolution
In
astronomy, stellar
evolution refers to the changes which stars undergo during
their lifetime. Stars change in color, luminosity,
size and temperature through their
lifespan. Scientist can not study an individual stars lifetime though
because they far exceed ours and therefore we must study stellar
evolution by observing
the life cycle of numerous stars, each at a different point in
its life cycle, and then running computer models which simulate the
structure of stars.
http://antwrp.gsfc.nasa.gov/apod/image/0503/foxfur_croman_big.jpg
Through history stars have been recorded, starting with the brightest,
which have been named going back as far as 1000 b.c. by the chinese.
Today we name stars in three categories, the first being the brightest
are named for what constellation
they are in. Variable stars
are the ones that change in luminosity periodically and the fainter
stars are logged in the Henry Draper
Catalogue under
numubers like HD 12938. Stars exist either alone
or in groups of two or more in a system or cluster. Large clusters are
grouped into galaxies and in our Galaxy, the Milky Way there are more than 100
billion stars. There are also 10's of millions of galaxies that are
part of the known universe. Think about that and tell me there's no
life out there.
