This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. Whether the universe will "end" at all is not certain ...

Andromeda and the Milky Way merge. NASA; ESA; Z. Levay and R. van der Marel, STScI; T. Hallas; and A. Mellinger Share Curious Kids is a series for children of all ages. If you have a question you’d ...