Enceladus is a medium-sized moon of Saturn made up of a crust of water-ice and an ocean of liquid water below. This ocean is in some senses similar to those on Earth and is connected directly to Encel

One of the most important features of extrasolar planets is whether they have an atmosphere or not. For astrobiology in particular, small, rocky planets blanketed with an atmosphere offer the best hop

While our planet only has one easily visible Moon, several other tiny objects arguably deserve the title too

We’ve had a few false alarms before – including fossilised microbes and signs of carbon dioxide production in Martian rocks – but NASA has now cautiously suggested it’s found signs that life once exis

Earth exists in a bubble. Our atmosphere forms a protective barrier between everything on the planet’s surface and the near-empty vastness of space. But it’s not the only bubble Earth sits inside. Bey

We humans are always wondering whether we’re alone in the Universe. But what if we are one of a long line of species that were around long before our planet even existed? This intriguing idea, that li