Study Notes forStudy Notes forChapter 30:Chapter 30:
Stars, Galaxies, and the Stars, Galaxies, and the UniverseUniverse
Chapter 30 Section Chapter 30 Section 1:1:
Characteristics of StarsCharacteristics of Stars
11 By analyzing the light that a star By analyzing the light that a star
emits, astronomers can determine emits, astronomers can determine the __________ and __________ of a the __________ and __________ of a star.star.
compositiontemperature
22 Scientists determine the Scientists determine the
composition and temperature of composition and temperature of stars by analyzing the ______ of the stars by analyzing the ______ of the light that stars emit.light that stars emit.
spectra
33 The _______ stars are ____ in color, The _______ stars are ____ in color,
the hottest stars are _____.the hottest stars are _____.coolest red
blue
44 Stars _______ to move in the sky Stars _______ to move in the sky
because ______ is moving.because ______ is moving.appear
Earth
55 A star moving away from the Earth A star moving away from the Earth
has a spectrum that is shifted has a spectrum that is shifted toward ______.toward ______.
red
66 A light-year is the distance _____ A light-year is the distance _____
travels in a year. travels in a year. light
77 About ______ stars are visible from About ______ stars are visible from
Earth without a telescope.Earth without a telescope.6,000
88 ________ magnitude is the ________ magnitude is the
brightness of a star as it appears brightness of a star as it appears from Earth.from Earth.
Apparent
99 ________ magnitude is the true ________ magnitude is the true
brightness of a star.brightness of a star.Absolute
Chapter 30 Section Chapter 30 Section 2:2:
Stellar EvolutionStellar Evolution
1010 After its temperature rises to After its temperature rises to
10,000,000°C, a _________ becomes 10,000,000°C, a _________ becomes a star when nuclear fusion begins.a star when nuclear fusion begins.protostar
1111 During the main sequence stage, During the main sequence stage,
________ fuses into _______ to ________ fuses into _______ to generate energy in a star’s core.generate energy in a star’s core.
hydrogenhelium
1212 A star with the sun’s mass would A star with the sun’s mass would
stay on the _____ sequence of the stay on the _____ sequence of the H-R diagram for about 10 billion H-R diagram for about 10 billion years.years.
main
1313 A large, bright star whose hot core A large, bright star whose hot core
has used most of its hydrogen is a has used most of its hydrogen is a _____._____.
giant
1414 A small, hot, extremely dense core A small, hot, extremely dense core
left after a star collapses is a _____ left after a star collapses is a _____ dwarf.dwarf.
white
1515 A white ______ is a hot, extremely A white ______ is a hot, extremely
dense core of matter left after a dense core of matter left after a star _________.star _________.
dwarfcollapses
1616 Many astronomers believe that Many astronomers believe that
black _______ do not exist.black _______ do not exist.dwarfs
Chapter 30 Section Chapter 30 Section 3:3:
Star GroupsStar Groups
1717 A galaxy is made of stars, dust, and A galaxy is made of stars, dust, and
gas bound together by _______.gas bound together by _______.gravity
Chapter 30 Section Chapter 30 Section 4:4:
The Big Bang TheoryThe Big Bang Theory
1818 Hubble’s discovery that there was Hubble’s discovery that there was
____ shift in the spectra of galaxies ____ shift in the spectra of galaxies lead to an understanding that the lead to an understanding that the universe is _________.universe is _________.
red
expanding
1919 Red shift in the spectra of galaxies Red shift in the spectra of galaxies
told ________ that the universe is told ________ that the universe is expanding.expanding.Hubble
2020 The ____ bang occurred about ___ The ____ bang occurred about ___
billion years ago.billion years ago.big 14
2121 Astronomers believe that cosmic Astronomers believe that cosmic
background ________ formed shortly background ________ formed shortly after the big bang.after the big bang.radiation
2222 Most of the universe is made of Most of the universe is made of
_____ energy and dark _______._____ energy and dark _______.dark
matter
THE ENDTHE END