Download Stars

Mrs. Gibson
 The
sun is medium sized
 In order from smallest to largest:
◦ Neutron star White dwarf
Medium sizedGiant Super giant
A
star’s color reveals its
temperature
 In order from coolest to hottest:
◦ Red Red/OrangeYellow
WhiteBlue
The brightness of a star depends on
size and temperature
 How bright a star looks depends on
distance from Earth and actual
brightness
 Apparent magnitude: brightness as
seen from Earth
 Absolute magnitude: brightness if it
were a standard distance from Earth

 Hertzsprung-Russel
diagram
shows the relationship between
surface temperature and
brightness
 More than 90% of stars are in the
main sequence where surface
temperature increases as
brightness increases
Lifetime depends on mass
 Less massive live longer
 A medium sized star will live about 10
billion years

◦ Astronomers believe that the sun is about
4.6 billion years old

Stars smaller than the sun can live up
to 200 billion years

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Nebula: large amount of gas & dust spread
out in an immense volume
Protostar: earliest stage in a star’s life
White Dwarf: remaining hot core of a star
after outer layers expand & drift out into
space
Supernova: Explosion of a dying giant or
super giant star
Black Hole: remains of an extremely massive
star pulled into a small volume by the force of
gravity