Earth
Sun
Moon
Earth, Sun, or Moon
Historical Contributions
100
Why the Earth orbits the sun
What is: gravity?
100
The path Earth takes as it moves around the sun
What is: orbit?
100
Why the moon orbits the Earth
What is: gravity?
100
It is a small, rocky satellite with temperature extremes, virtually no atmosphere, no water, no life.
What is the moon?
100
This Polish astronomer theorized that the planets revolved around the sun.
What/who is: Nicolaus Copernicus?
200
The length of time it takes for the Earth to make one complete rotation
What is: 24 hours (one day)?
200
The sun is an average-sized one of these.
What is: a star?
200
The approximate length of time it takes the moon to revolve around the Earth
What is: once a month?
200
A large sphere of hot gas with a surface temperature of 10,000 degrees Fahrenheit
What is the sun?
200
This Italian scientist was the first to use a telescope for astronomy.
What/who is: Galileo Galilei?
300
The length of time it takes the Earth to make one complete revolution
What is: one year (365 days)?
300
About 4.6 billion years
What is: the age of the sun?
300
When the moon moves directly between the sun and Earth so that all three are lined up in a straight line
What is a solar eclipse?
300
The Earth's surface is covered by this percentage of water.
What is: 70%?
300
This Egyptian astronomer believed that the planets and sun orbited the Earth.
What/who is: Claudius Ptolemy?
400
When the Earth passes between the sun and moon
What is a lunar eclipse?
400
93 million miles (150 million kilometers)
What is: the distance of the sun from the Earth?
400
The number of days the phases of the moon appear in a pattern that repeats itself
What are: 29 1/3 days?
400
The Earth's atmosphere protects us by blocking out most of this from the sun.
What are: the sun's damaging rays?
400
This Greek believed that the Earth was a sphere and that the universe was spherical.
What/who is: Aristotle?
500
The tilt of the Earth's axis during its revolution around the sun
What is: the reason why we have seasons?
500
The sun has enough of this gas to stay shining for about 4 billion years.
What is: hydrogen?
500
The phases of the moon in order, beginning with the new moon
What are: New moon - waxing crescent - first quarter - waxing gibbous- full moon - waning gibbous - last quarter - waning crescent?
500
The Earth, sun, and moon listed in order according to size, beginning with the smallest
What are: moon, Earth, sun?
500
These exploration missions have added greatly to our understanding of the moon.
What are: the NASA Apollo missions?
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