Name: Date: Block:
Astronomy Summary 2017
1. What is the difference between rotation and revolution?
· Earth’s rotation – spinning on its axis
· Earth’s revolution – yearly orbit around the Sun
2. How long is Earth’s rotation and revolution?
· Earth’s rotation – 24 hours
· Earth’s revolution – 365 days 6 hours
3. What causes day and night?
· Earth’s rotation – side of Earth facing the Sun is in daytime, while the side away from the Sun is nighttime
4. What causes the seasons?
· The tilt of the Earth
· Earth’s revolution around the Sun
5. What is the shape of the Earth’s orbit around the Sun?
· An ellipse (oval)
6. When is the Earth closest to the Sun?
· during the winter
· farthest from the Sun during summer
7. What is leap year?
· A year when an extra day is added to the calendar in February
8. How often does the leap year occur? Why?
· It occurs every 4 years
· The Earth revolves around the Sun every 365 days and 6 hours. Our calendar is only 365 days. To make up for the missing 6 hours every calendar year, we must add 1 day to the calendar every 4 years (6 hours x 4 years = 24 hours)
9. What is the difference between the equinox and solstice?
· Equinox – 2 days a year when there is equal day and night
· Solstice – they day during the year that has the longest amount of sunlight and the day with the shortest amount of sunlight
10. When does the equinox and solstice occur?
· Equinox – 1st day of Fall and Spring
· Solstice – 1st day of Summer (longest period of sunlight) and 1st day of Winter (shortest period of sunlight)
11. What is a lunar eclipse?
· The Sun, Earth, and Moon are in a line and Earth’s shadow falls on the Moon
· Appears to go through the moon phases and turn red during totality because the sunlight traveling through Earth’s atmosphere bends and reflects on the Moon.
· Can only occur at night during a Full Moon.
12. What is a solar eclipse?
· The Sun, Moon, and Earth are in a line. The Moon blocks out the Sun.
· Can only occur during the day, during a New Moon
13. What causes tides?
· The gravitational pull of the Moon and the Sun
· The gravitational pull of the Moon has a greater effect on Earth.
14. When do tides occur?
· Every 6 hours
· 2 high tides and 2 low tides a day – they alternate
15. What is the difference between a high tide and a low tide?
· During a high tide, the water level rises
· During low tide, the water level lowers
16. Why does the moon appear to change shape in a lunar month?
· The relative position of the Sun, Earth, and Moon changes throughout the lunar cycle.
17. Why do we only see one side of the Moon?
· The Moon rotates and revolves at the same speed (approximately every 28 days).
18. Review the moon phases and the location of the sun, Earth, and moon that create each phase.
· Be able to identify all phases – full moon, new moon, 1st quarter, 3rd (last quarter), waxing gibbous, waxing crescent, waning gibbous, waning crescent
19. What are constellations?
· A group of stars that forms a pattern in the sky that looks like a familiar object, animal, or character
20. Why do constellations appear to change in the sky?
· As Earth rotates, the constellations appear to move.
· As Earth revolves around the Sun, you see different constellations as others disappear.
· Some constellations are visible all year because of their location
21. What is a galaxy?
· A large group of stars, dust, and gas held together by gravity
22. What galaxy do we live in?
· Milky Way – it is a spiral galaxy
23. Name the 3 types of galaxies and describe their shape.
· Spiral galaxy – looks like a pinwheel
· Oval galaxy – looks like a flat disc, an oval Frisbee
· Irregular galaxy – has no definite shape
24. What is the difference between comets, asteroids, meteoroids, meteors, and meteorites?
· Comet – space object made of dust and rock particles mixed with frozen water, methane and ammonia; creates a “tail” as it approaches the Sun
· Asteroid – a large piece of rock or metal made up of material similar to that which form the planets, mostly found in the asteroid belt
· Meteoroid – a piece of rock or metal traveling in space
· Meteor – a meteoroid that burns up in Earth’s atmosphere
o “shooting stars”
· Meteorite – a meteoroid that strikes the surface of a moon or planet
25. What is the asteroid belt? Where is it located?
· A collection of asteroids located between Mars and Jupiter
26. Explain the relationship between mass, gravity, and weight.
· Mass – the amount of matter “stuff” an object has
· Gravity – an attractive force between objects that have mass
· Weight – gravity’s effect on an object’s mass
· More mass = more gravity
· More gravity = more weight
* Don’t forget to review your vocabulary!