SWEET MYSTERY OF LIFE, AT LAST I'VE FOUND YOU

摘要

When life was first cooked up on Earth billions of years ago, some of the ingredients may have been flown in by extraterrestrial visitors. Not by starship-piloting aliens, but by bits of asteroids and cornets that fell from the sky when the planet was still a lifeless ball of rock. Scientists have long known that some meteorites contain basic chemicals needed for life, such as amino acids. Now a study of two 4.5-billion-year-old meteorites has found another ingredient in the primordial soup: sugar.