Jupiter's moon Ganymede, is larger than the planet Mercury!
149
The Earth weighs around 6,600,000,000,000,000,000,000 tons (5,940 billion billion metric tons)!
221
The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
147
Summer on Uranus lasts for 21 years.
358
On Titan, Saturn's largest moon, the atmosphere is so thick and the gravity so low that humans could fly through it by flapping "wings" attached to their arms.
7
Saturn's rings are about 500,000 miles in circumference but only about a foot thick.
160
The population of the Earth has more than doubled since 1950.
151