Environment Why we urgently need to talk about geoengineering The idea that we might attempt large-scale experiments to cool the planet is horrifying to some, but it looks increasingly likely that we will have to do so this century Comment
Mathematics Mathematicians are chasing a number that may reveal the edge of maths Some numbers are so unimaginably large that they defy the bounds of modern mathematics, and now mathematicians are closing in on a number that may mark the edge of this bizarre abyss News
Space Otherworldly space images from a major photography competition From a silhouetted space station to glowing comet tails and swirling stars, this year's ZWO Astronomy Photographer of the Year contest inspires us to see the cosmos in a new light Regulars
Life The truth about de-extinction: is it even possible, and why do it? Ambitious projects aim to put dire wolves, woolly mammoths and passenger pigeons back into our ecosystems. But with so many technical and ethical hurdles, what is the real motivation? Features
Technology New book is an illuminating but flawed look at the impact of emoji Emoji add a new depth to communications, but what of their cultural impact? Keith Houston's Face with Tears of Joy offers some answers Culture
Earth We've found that a new type of rock is forming from old slag heaps Scientists have discovered a new type of sedimentary rock made of debris from slag heaps, formed in the geological blink of an eye. Could this be good news, asks Graham Lawton Comment
Comment Pink Floppy Disc and The Bitles: Embracing the future of AI music Feedback tries to work out if a new indie rock band is releasing AI-generated music, and eventually decides to lean into this as the future Regulars