What if outer space isn’t empty, but behaves like a thick, slow-moving fluid? Anew study suggests just that, and it could help solve a puzzling mismatch between current models of the universe and ...

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, ...

This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. At an internal staff briefing last week, acting NASA ...

Right above you is the sky – or as scientists would call it, the atmosphere. It extends about 20 miles (32 kilometers) above the Earth. Floating around the atmosphere is a mixture of molecules – tiny ...