Asteroids – rocky objects near the Earth orbiting the sun – are the parent bodies of most meteorites. The theory suggests that chemical reactions in asteroids can create some of the elements necessary for life.
Scientists have found sugars such as arabinose and xylose – but the most significant discovery was ribose.
Ribose plays an extremely important role in our human biology. It exists in our RNA (ribonucleic acid) molecules and provides messages from our DNA to help build proteins for our body, according to a press release.
"It's amazing that such an ancient material could detect a molecule as delicate as ribose," said Jason Dworkin of NASA, co-author of the study, in a press release.
The discovery of ribose also suggests that RNA has evolved before DNA, giving scientists a clearer picture of how life could arise.
DNA has long been considered a "lifelong template" – but according to a press release, RNA molecules have more options such as replication without the help of other molecules. These additional possibilities, combined with the fact that scientists have not yet found sugars in DNA in meteorites, support the theory that "RNA coordinated the machinery of life before DNA."
"The study provides the first direct evidence of the existence of ribose in space and the supply of sugar to Earth," said Yoshihiro Furukawa of Tohoku University, Japan's main study author, in a press release. "Extraterrestrial sugar may have contributed to the creation of RNA on prebiotic Earth, which probably led to life."
Of course, there is a possibility that the meteorites have been contaminated by life on Earth – but tests have shown that this is unlikely and sugars probably come from space.
Now scientists will continue to analyze meteorites to see how abundant these sugars are and how they could affect life on Earth.