Transcript Life Cycle of a Star

Life Cycle of a Star
 1st
Stage of Life
 Ball of gas and dust that is pulled
together by gravity
 Nuclear fusion starts as gas cloud
becomes denser and hotter
 Nuclear Fusion hydrogen atoms fuse
into helium
 Creates the intense energy found in stars
 Four
types of stars make up the
life of a star
Main Sequence
Giants
Super Giants
White Dwarfs
 Main
Sequence (the Sun)
 2nd stage
 Longest stage
 Hydrogen changes into helium which
creates enormous amounts of energy
 The size of the star does not change
much
 Giants
and Supergiants
 3rd stage
 Main Sequence star becomes a red
giant
 Red giant star that expands and cools
once it loses all its hydrogen
 Center shrinks and atmosphere grows
large and cools
Dwarf small hot star
that is the leftover center of an
older star
Final stage
Can shine for billions of years
before they extinguish
 White
 Hertzprung-Russell
Diagram
Shows the relationship between a
star’s surface temperature and
absolute magnitude
Used to study the lives of stars
Most stars lie along the main
sequence portion of the diagram
 Age
of stars
Average stars become red
giants then white dwarfs
More massive stars explode
into a variety of objects
Supernova gigantic explosion in which a
massive star collapses
 Occurs after a massive star uses up its
fuel source
 Neutron Star a star that has collapsed to
a point at which all particles are neutrons
 A neutron star that spins and sends out
beams of radiation is called a pulsar

 Black
Hole an object that is so
massive that light cannot escape
its gravity
Remnants of a supernova
Astronomers can detect black
holes by using X-ray telescopes
Question 1
What
sun?
kind of a star is the
Answer
Main
Sequence
Question 2
What
is the H-R diagram?
Answer
A
graph that shows the
relationship between a star’s
temperature and absolute
magnitude
Question 3
What
are the four main
types of stars?
Answer
Main-Sequence
Giants
and Supergiants
White Dwarfs