There are two golf balls sitting on the moon.
721
There are 5 to 10 times more stars in the known Universe than there are grains of sand on all the world's beaches, but a single grain of sand has more atoms than there are stars in the known Universe.
20
Any space vehicle must move at a rate of 7 miles per second in order to escape the earth's gravitational pull.
121
Saturn's rings are about 500,000 miles in circumference but only about a foot thick.
160