In a few hours, a spacecraft should blast-off from Florida on the hunt for signs of alien life. Its destination is Europa, a deeply mysterious moon orbiting the distant planet Jupiter. Trapped under its icy surface could be a vast ocean with double the amount of water on Earth. The Europa Clipper spacecraft will chase a European mission that left last year, but using a cosmic piggyback, it will overtake and arrive first. That won’t be until 2030 but what it finds could change what we know about life in our solar system. Years in the making, the Europa Clipper launch was delayed at the last minute after hurricane Milton blasted Florida this week. The spacecraft was rushed indoors for shelter, but after checking the launchpad at Cape Canaveral for damage, engineers have now given the go-ahead for lift-off at 1206 local time (1706 BST) on 14 October. “If we discover life so far away from the Sun, it would imply a separate origin of life to the Earth,” says Mark Fox-Powell, a planetary microbiologist at the Open University. “That is hugely significant, because if that happens twice in our solar system, it could mean life is really common,” he says. Located 628 million km from Earth, Europa is just a bit bigger than our moon, but that is where the similarity ends. If it was in our skies, it would shine five times brighter because the water ice would reflect much more sunlight. Its icy crust is up to 25km thick, and sloshing beneath, there could be a vast saltwater ocean. There may also be chemicals that are the ingredients for simple life. Scientists first realised Europa might support life in the 1970s when, peering through a telescope in Arizona, they saw water ice. Voyager 1 and 2 spacecrafts captured the first close-up images, and then in 1995 Nasa’s Galileo spacecraft flew past Europa taking some deeply puzzling pictures. They showed a surface riddled with dark, reddish-brown cracks,... |