An ancient Martian system of canyons and valleys could be home to archaic life forms, a ground-breaking scientific paper has found. Scientists investigating the Red Planet’s mind-boggling cave system ...

Deep in Vietnam’s jungle lies Son Doong, the largest cave on Earth, where underground rivers, ancient jungles, and skyscraper-high chambers create an alien world. Discovered only in 2009, it’s ...

From lava tubes on Mars to ice pockets on Europa, subterranean environments may offer the best chance of finding life—and living safely—beyond our planet. “I was like, ‘OK, I'm pretty sure that ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

Could ancient humans really have built the pyramids without extraterrestrial help? Or do such questions reveal more about modern anxieties than the past itself? The idea that aliens assisted the ...