1. Astronomers study the planets ___ our solar system.
a. among
b. below
c. in
2. Stars are balls of gas that give ___ light.
a. away
b. in
c. out
3. A galaxy is a system ___ stars.
a. of
b. off
c. with
4. Would you like to live ___ the moon?
a. at
b. in
c. on
5. The Chinese Wall can be seen ___ the moon.
a. along
b. from
c. through
6. A "light year" is the distance covered ___ light travelling during one year.
a. after
b. by
c. for
7. Lunar months are ___ than our months.
a. more short
b. shorter
c. shortier
8. Man first landed on the moon ___ 1969.
a. afterwards
b. in
c. since
9. A crater is a hole ___ the ground.
a. below
b. in
c. off
10. Gravity is the force that attracts objects in space ___ each other.
a. after
b. between
c. towards