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

Might our universe – as vast as it is – be simply one of many? We look at the growing evidence that there’s more than one cosmos out there

When comet 3I/ATLAS was discovered in July, on a one-way interstellar journey through our Solar System, Harvard astronomer Avi Loeb suggested it might be an alien spacecraft paying us a visit. Back in

A mosaic image of Enceladus created from data ...

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

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