Add Yahoo as a preferred source to see more of our stories on Google. Right above you is the sky – or as scientists would call it, the atmosphere. It extends about 20 miles (32 kilometers) above the ...

What can galaxies smaller than our Milky Way Galaxy teach scientists about dark matter, which remains one of the most mysterious substances in the universe? This is what a recent study published in ...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. What is beyond outer space? – Siah, age 11, ...