This article was originally published at The Conversation. The publication contributed the article to Space.com's Expert Voices: Op-Ed & Insights. The size of the solar system is defined by the volume ...

An asteroid 20 times larger than the one that may have wiped out the dinosaurs struck Jupiter's moon Ganymede some 4 billion years ago, dramatically shifting the possibly life-hosting satellite's axis ...

Titan, the second largest moon in the Solar System—indeed, it is even larger than the planet Mercury—draws attention not only because of its size, but also due to its dense, hazy atmosphere, an ...