Venus's surface may always have been too hot for oceans

摘要

VENUS might never have had the conditions necessary for water to exist on its surface, meaning the planet wouldn't have been habitable as once thought. Today, Venus is a hellish world, with temperatures on its surface hot enough to melt lead. Yet the presence of water vapour in its thick atmosphere, coupled with surface features known as tesserae that look like ancient continents, suggest it could once have supported oceans and maybe life billions of years ago. Three new Venus spacecraft, two from NASA and one from the European Space Agency (ESA), were recently selected for launch in the next decade, partly to investigate this possibility.