Transcript Life Cycle of a Star

Life Cycle of a Star
Waves, Atoms and Space
Stage 1
Protostars
Protostars
• Huge clouds of gas
(hydrogen) in which
stars are made.
• Many thousands of
times bigger than our
solar system
• As the clouds
collapse stars are
born in them
Stage 2
Main sequence star
Main Sequence Star
• E.g. Our sun
• Sequence lasts for
about 10 000 million
years
• Our sun is about half
way through it’s main
sequence
Stage 3
Red Giant
Red Giant
• As the sun runs out of
hydrogen the outer
layers of the sun will
become cooler
• They will also expand
massively.
• The Earth (along with
Mercury, Venus and
Mars) will be
swallowed up.
Stage 4
White Dwarf
White Dwarf
• Gravity will cause the
red giant to collapse
• The sun is now much
cooler and it
collapses into a small
white star
• It still has the same
mass as the original
sun!
Stage 5
Black Dwarf
Black Dwarf
• The sun cools more
and more
• Eventually it will
become a black mass
emitting no light
• It will then spend the
rest of eternity drifting
silently through space
Stars bigger than our sun!
At least four times bigger (you
don’t need to know about these
for your exams)
Stage 4
(for a big star)
Red Supergiant
Stage 5
(for a big star)
Supernova
Supernova!
• The largest and most
powerful explosions in
the universe.
• The red supergiants
literally blow
themselves apart!
Supernova
• All the atoms we are
made from came
originally from these
giant supernova
explosions.
Stage 6
(for a big star)
Black hole
Black hole
• After the supernova a
huge mass is left
behind.
• There is so much
mass its gravity
prevents even light
from leaving it
• Black holes can suck
in nearby stars and
solar systems.
• Luckily there are no black holes any where
near our sun!