Mars had an oxygen-rich atmosphere around 4 billion years ago
13
Saturn's rings are about 500,000 miles in circumference but only about a foot thick.
160
A comet's tail always points away from the sun.
2
Summer on Uranus lasts for 21 years.
358
Buzz Aldrin’s mother’s maiden name was Moon.
9
It would take more than 150 years to drive a car to the sun.
569
Scientists have confirmed that Enceladus, one of Saturn’s moons, has a watery ocean.
6