Explorations: Introduction to Astronomy Midterm study
guide
1. astronomy: study of the universe
2. Radius of Earth: 4,000 miles or 6,000 km
3. Distance from earth to the moon: 240,000 miles or 380,000 km
4. 1 astronomical unit is equivalent to: 93 Million Miles or 150 million kilometers
5. speed of light: 300,000 km/s
6. Constellations: A group of stars that forms a shape or pattern.
7. Projection effect: Stars of a constellation appearing to be close to another when
they're actually far away.
8. Two categories of stars: Stars that rise along the Eastern Horizon and set along
the Western Horizon
9. circumpolar stars: Stars that circle the celestial pole and never move below the
horizon.
10. Why do we observe stars moving from East to West through the night?: The
Earth rotates on it's axis from West to East once every 24 hours.
11. Celestial Sphere: Imaginary sphere of the Celestial objects that seems to
center on the Earth
12. celestial equator: The projection of the earth's equator onto the celestial sphere
13. celestial poles (north and south): Projection of Earth's North and South Poles
onto the celestial sphere. Creates North and South celestial pole.
14. Sun's Daily Motion: Rises along the eastern side of the horizon and moves
across the sky. Reaches max altitude around noon and sets along the western
horizon.
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, 15. Sun's Annual Motion: The sun does not have a fixed position on the celestial
sphere.It completes a full path along the celestial sphere through the zodiac constellation
16. The path that the Sun follows through the stars on the celestial sphere is
known as: Ecliptic
17. Zodiac: constellations along the ecliptic. though which the sun passes
18. spring/fall equinox: March 20th and September 22nd (both have the same
pattern)
19. The Ecliptic is not aligned with the celestial equator at: spring and fall
eqiunoxes
20. What causes the seasons?: The tilt of the Earth's axis by 23.5%
21. Earth is 3 million miles closer to the sun in _________ than in July: January
22. We experience Summer in June in the Northern Hemisphere because: The
northern hemisphere is tilted toward the sun.
23. Daily Motion of the Moon: Rises along the Eastern Horizon and sets along the
Western Horizon
24. Long term motion of the moon: The Moon doesn't have a fixed position on the
celestial sphere, it shifts eastward among the background stars
25. Prograde motion: The eastward motion with respect to the background stars
(Rises West to East)
26. A solar eclipse occurs when: the moon eclipses the sun(aka passes in front
of the sun) Occurs at a new moon
27. Lunar Eclipse: Occurs when the moon passes in the shadow of the earth. (must
be a full moon for it to happen)
28. Why don't eclipses happen every month?: The moon's orbit is tilted with
respect to earth's. orbit
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guide
1. astronomy: study of the universe
2. Radius of Earth: 4,000 miles or 6,000 km
3. Distance from earth to the moon: 240,000 miles or 380,000 km
4. 1 astronomical unit is equivalent to: 93 Million Miles or 150 million kilometers
5. speed of light: 300,000 km/s
6. Constellations: A group of stars that forms a shape or pattern.
7. Projection effect: Stars of a constellation appearing to be close to another when
they're actually far away.
8. Two categories of stars: Stars that rise along the Eastern Horizon and set along
the Western Horizon
9. circumpolar stars: Stars that circle the celestial pole and never move below the
horizon.
10. Why do we observe stars moving from East to West through the night?: The
Earth rotates on it's axis from West to East once every 24 hours.
11. Celestial Sphere: Imaginary sphere of the Celestial objects that seems to
center on the Earth
12. celestial equator: The projection of the earth's equator onto the celestial sphere
13. celestial poles (north and south): Projection of Earth's North and South Poles
onto the celestial sphere. Creates North and South celestial pole.
14. Sun's Daily Motion: Rises along the eastern side of the horizon and moves
across the sky. Reaches max altitude around noon and sets along the western
horizon.
1
, 15. Sun's Annual Motion: The sun does not have a fixed position on the celestial
sphere.It completes a full path along the celestial sphere through the zodiac constellation
16. The path that the Sun follows through the stars on the celestial sphere is
known as: Ecliptic
17. Zodiac: constellations along the ecliptic. though which the sun passes
18. spring/fall equinox: March 20th and September 22nd (both have the same
pattern)
19. The Ecliptic is not aligned with the celestial equator at: spring and fall
eqiunoxes
20. What causes the seasons?: The tilt of the Earth's axis by 23.5%
21. Earth is 3 million miles closer to the sun in _________ than in July: January
22. We experience Summer in June in the Northern Hemisphere because: The
northern hemisphere is tilted toward the sun.
23. Daily Motion of the Moon: Rises along the Eastern Horizon and sets along the
Western Horizon
24. Long term motion of the moon: The Moon doesn't have a fixed position on the
celestial sphere, it shifts eastward among the background stars
25. Prograde motion: The eastward motion with respect to the background stars
(Rises West to East)
26. A solar eclipse occurs when: the moon eclipses the sun(aka passes in front
of the sun) Occurs at a new moon
27. Lunar Eclipse: Occurs when the moon passes in the shadow of the earth. (must
be a full moon for it to happen)
28. Why don't eclipses happen every month?: The moon's orbit is tilted with
respect to earth's. orbit
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