1. Because only hydrogen and helium are not made in stars, about 90 percent of the human body is composed of (as Carl Sagan put it) “star stuff.”
2. Bee stings are acidic, whereas wasp stings are alkaline (basic).
3. Helium’s freezing point is so low that currently there’s no such thing as solid helium.
4. If elemental sodium comes in contact with water, the reaction is so exothermic that it creates fire.
5. Gliese 436 b is a planet literally made of burning ice. The atmosphere is composed of a white-hot substance so tightly packed that it can’t become gaseous or liquid: in other words, burning ice.
6. In the time since it was discovered, in 1930, Pluto has never made a full revolution around the sun.
7. Because there’s no gravity to separate gases, solids and liquids, it’s impossible to belch in space.
8. Part of the static on old TVs is leftover radiation from the
9. If you look through a telescope at a planet that’s light-years away, you’re seeing that planet’s past.
10. Hot water freezes faster than cold water.
11. If you stand on the equator or with the moon directly overhead, the gravitational forces make you weigh slightly less that you would elsewhere.
12. There is a disease called Ondine’s curse that makes people lose the ability to breathe automatically while sleeping,
resulting in death.
13. There is more genetic difference between individual chimpanzees than there is between individual human beings.
14. The only creatures that can suffer from leprosy are humans and armadillos, who can also infect each other.
15. Giraffes only sleep 20 minutes per day.