Asteroid samples reveal RNA building blocks for life on Earth.

Scientists have discovered the chemical compound uracil, one of the building blocks of RNA, in just 10 milligrammes of material from the asteroid Ryugu, according to new research published on Tuesday. The finding lends weight to a longstanding theory that life on Earth may have been seeded from outer space when asteroids crashed into our planet carrying fundamental elements. The discovery offers "strong evidence that one of the RNA components has been provided to the Earth even before the emergence of life", said Yasuhiro Oba, associate professor at Hokkaido University and an author of the research.