Roughly 14 billion years ago, a tiny pinpoint of extreme heat and density erupted in a grand explosion, leading to the creation of between 100 billion and 2 trillion galaxies, one of them being our ...

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 [email protected]. How will the universe end? – Iez M., age 9, ...