planets
the sun
the moon
miscellaneous
numbers
100
This is the planet that is closest to the sun.
What is Mercury?
100
The type of solar weather pictured in this satellite image: 
What is a Coronal Mass Ejection?
100
The moon is a natural type of this that revolves around a bigger object.
What is a satellite?
100
The reason the Moon shines brightly
What is because the sun reflects off the surface of the moon
100
The number of planets that do NOT have a moon
What is 2? (Mercury and Venus)
200
This is the largest planet in our solar system
What is Jupiter?
200
This is the process by which the sun gives off solar radiation throughout the solar system
What is (Hydrogen) fusion?
200
These are hollow pits on the surface of the moon.
What are craters?
200
Earth's seasons are caused by these 2 things
What is the slight tilt of the Earth and its position as it rotates around the sun?
200
The unit that describes how far the Earth is from the Sun
What is an astronomical number? 
300
This is what all the planets have in common
What is "they revolve around the sun?"
300
It takes the earth 365 days to do this.
What is revolve (orbit) around the sun?
300
The moon's gravitational pull causes this rise and fall of the ocean.
What are tides?
300
The only other planet in our solar system that humans have landed equipment on
What is Mars?
300
The sun contains this approximate amount of mass in our solar system
What is 99%?
400
These are the terrestrial planets that have a hard, rocky surface
What are Mercury, Venus, Earth, and Mars?
400
This is how long it takes earth to complete one rotation.
What is 24 hours --or one day?
400
The name of the moon phase pictured here:
What is waxing crescent?
400
A cosmic snowball of frozen gases, rock, and dust that orbits the Sun.
What is a comet? 
400
It takes this many minutes for sunlight to reach the Earth
What is 8 minutes?
500
These are the gas giants that have no known hard surface
What are Jupiter, Saturn, Uranus, and Neptune?
500
All 6 layers of the sun from most to least dense
What are the core, radiation zone, convection zone, photosphere, chromosphere and corona?
500
The distance the Moon is traveling away from the Earth every year
What is 4 centimeters (approximately)
500
The name of a planet found in another solar system
What is an exo-planet?
500
A year on Mars takes this many (Earth) days
What is 687 days?