Download Star Lifecycle basic cgs

Life Cycle of a Star
Stage 1 (Nebula)
• A nebula is a cloud of dust
and gas, composed primarily
of hydrogen
• Birthplace of stars
Cone Nebula
Ring Nebula
Rosetta Nebula
Eagle Nebula
Stage 2 (Main Sequence Stage)
• Longest stage of stars life (90%)
• Nuclear Fusion is occurring Hydrogen (H)
is being converted into Helium (He)
• Stage our sun is in!
Stage 3 (Red Giant)
Massive & Super massive = Super red giant
• Star runs out of
hydrogen and
uses Helium as it
fuel source.
• Helium changes
into Carbon
• Grows very large
/ gets cooler on
the surface.
Our sun
HR Diagram
(Hertzsprung-Russell diagram)
• Show relationship between luminosity (brightness) and temperature
90% of stars ar
Main Sequenc
Our Sun
Stage 4 (nova)
Massive & super massive = Supernova
• Massive stars will
Supernova
• Brilliant explosion
• Results in a white
dwarf, pulsar, or black
hole depending on
mass of star.
Crab Nebula – went
supernova in 1054
End Stage of a massive star
(Neutron Star/Pulsar)
• A star at least 2X more
massive than our sun
collapsed into a space
the size of a small city.
• So dense a teaspoon
of a neutron star would
weight more than a
cruise ship full of
people.
http://library.thinkquest.org/25763/lsupernova.htm
X-ray
Crab Nebula containing a Neutron Star
Went Supernova in 1054
End Stage Super Massive Star
(Black Hole)
• Only occurs with very
massive stars (3+
times the mass of our
sun)
Our Sun’s fate
• After main sequence,
stages differ!!!!!
• Our sun is not massive
enough to become a black
hole or a neutron star.
After it becomes a red
giant it will Nova and form
a…
Planetary Nebula
White Dwarf
White Dwarf
White Dwarf
• The White Dwarf will
burn very hot (Up to
20,000 degrees
Kelvin).
• Eventually it will burn
out and become a
Black Dwarf.
HR - Diagram
Important Stars
http://seds.org/messier/
Constellation –
A pattern created
by stars.
• Orion
– Stars:
• Betelgeuse
– (red supergiant)
• Rigel
– (blue giant)
Not all stars: Nebulas
The Brightest Star: Sirius
(Not including the sun)