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Earth Science

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The sun is a_.
main-sequence star
What is the next stage in the sun's life cycle?
red giant
What will be the final stage in the sun's life cycle?
black dwarf
Light cannot escape the intense gravitational pull of a_.
black hole
Our galaxy is called the_.
Milky Way
At its nucleus, the Milky Way Galaxy is about 100,000 light-years wide and_.
10,000 light-years thick
Where is our sun located in the Milky Way?
within one of the spiral arms
About 60 percent of all known galaxies are classified as_.
elliptical galaxies
According to Hubble's law, galaxies are retreating at a speed that is proportional to their_.
distance
Which of the following indicates that the universe is expanding?
red shift of distant galaxies
Based on the observed red shifts in the spectral lines of distant galaxies, astronomers conclude that_.
the universe is expanding
Greater red shifts in the spectra of galaxies indicate_.
faster speeds
According to the big bang theory, the universe began about_.
13.7 billion years ago
Patterns of stars are called what?
constellations
The most basic way to measure the distance to a star_.
parallax
Which factors determine a star's apparent magnitude?
size, tempature, distance
What are the two main types of bright nebulae?
emission nebula, and reflection nebula
What happens to a low mass star when it depletes its hydrogen fuel?
it collapses into a white dwarf
What is a galaxy?
a group os stars,dust, and gases held together by gravity
Describe each step of the sun's life cycle.
red giant, planetary nebula, white dwarf, black dwarf