Astronomy CA REVIEW
Topics:
Star Characteristics
Star Life Cycles
Galaxies
Earlier topics are under Files:
3-1 REVIEW and 3-2 REVIEW
We are learning to: examine the life cycle of a star (characteristics; HR
diagram)
We are looking for: a description of how stars are classified by
characteristics and then organized on an HR diagram.
Characteristics
Size- Giant, main sequence, and dwarf
Temperature- blue=hot; red=cooler
Brightness- apparent brightness and absolute magnitude
HR diagram shows temperature, brightness, color of stars and where the
star is in its life cycle.
Used to graph the surface temperature (x-axis) vs. brightness (y-axis)
Hotter stars are on left side of graph; cooler stars on the right side of the
graph
Brighter stars on top of graph; dimmer stars on bottom of graph
Which characteristic of stars cause them
to be different colors?
a) chemical
composition
b) distance
c) size
d) temperature
e) I need help.
Which color would describe the youngest
and hottest star?
a)
b)
c)
d)
e)
blue
red
orange
yellow
I need help!
Which star would be the brightest if all the
stars are the same distance from Earth?
20% 20% 20% 20% 20%
a)
b)
c)
d)
e)
Main sequence
Neutron Star
Red super giants
White dwarf
I need help.
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How would you classify our star, the sun,
on the H-R diagram?
Main sequence
Red giant
White dwarf
Red supergiant
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a)
b)
c)
d)
e)
We are learning to: Examine the life cycle of a star and predict the next
likely stage .
We are looking for: progression of the stages of a star’s life
Nebulae- cloud of gas and dust
Protostar- fusion begins
Main sequence- average star
Giant/red-giant- more massive stars
Nova/supernova - exploding star
White dwarf- no nuclear process
Black dwarf- no heat or light
Black Hole (area of large gravitational attraction) or Neutron star (very
dense star)
If given a protostar, what is the next likely
stage of the star?
Super Giant
Nova
Main Sequence
Neutron Star
I need some help
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a)
b)
c)
d)
e)
What is the first stage of the birth of a
star?
Main sequence
Nebula
Giant
Dwarf
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What happens to the most massive stars as
they near their death?
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a) super nova to a
black hole
b) super nova to a red
giant
c) becomes a white
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d) nothing happens
e) I need some help.
What is the next likely stage of our sun?
White dwarf
Black dwarf
Red giant
Super nova
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a)
b)
c)
d)
e)
We are learning to: explain that universe has
billions of galaxies and are classified by shape
We are looking for: shapes of galaxies
•Spiral- mix of old and new stars
•Elliptical- more developed galaxies with older
stars
•Irregular-newer galaxies with newer stars
By what are galaxies classified?
Color
Temperature
Size
Shape
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a)
b)
c)
d)
What type of galaxy is illustrated in the
following picture?
a)
b)
c)
d)
Irregular
Spiral
Elliptical
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need help!
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What type of galaxies contain older stars?
Elliptical
Irregular
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