All about Space's secrets

Space is filled with secrets... but let's discover some!
1. Space is silent. There is not a single sound.
2. 100 million years, is the time it will take for the footprints of the astronauts from the Apollo mission to disappear.
3. The Earth orbit is surrounded by 500,000 pieces of junk left from satellites and the International Space Station.
4. The universe is composed of more than billion trillion of stars. It's more than all of the grains of sand of all the beaches on Earth.
5. On Mars, each time the sun sets it appears blue.
6. The sun is so big that one million Earths could fit inside.
7. You can't walk on Jupiter, Saturn, Uranus or Neptune because the surface is not solid.
8. If two pieces of the same metal are in space and touch, they would stick to each other and never separate.
9. Comets are created from the explosion of the solar system. About 4.5 billion years ago. They are composed of sand, ice and carbon dioxide.
And we still have much to learn!