1. When astronauts came back from the Moon, they had to go through US customs
They had many moon rock and dust samples to declare.
2. It may rain diamonds on Neptune and Uranus
According to researchers at UC Berkeley, both planets contain high proportions of methane, which could turn into diamonds at the high temperatures and pressures found there.
3. On Venus, a day is longer than a year
A day is calculated as the amount of time it takes for a planet to complete a rotation on its own axis, whereas a year is measured as the amount of time it takes for a planet to go around the sun. Measured in Earth days, a Venusian day is slightly over 243 days, but a Venusian year is only 225 days.
4. Humans could walk on water on the Moon
The highest percentage of Earth’s gravity at which people can walk on water is 22 percent. Thus, we could walk on water on Pluto or on the Moon, but not on any of the actual planets in our solar system.
5. 99 percent of our solar system’s mass is in the sun
It is about the size of one million Earths.
6. If two pieces of the same type of metal touch in space they bond permanently
This doesn’t happen on Earth because air and moisture create a barrier. Since the tools that astronauts use come from Earth, they are protected by a layer of oxidation and don’t have this problem. However, the effect could lead to neat applications for space travel.
7. Footprints on the moon will remain for 100 million years
They will never erode because there is neither water nor wind on the Moon. However, they could eventually get hit by a meteorite, which would destroy them.
8. Apollo 11 astronauts used autographed pictures as life insurance policies
Since they couldn’t get life insurance, they distributed autographed pictures to friends and family that were postmarked on important dates that could be sold and used instead of life insurance if they didn’t make it back to Earth.