New discovery suggests life on Earth may have come from space
This is a colored view of the C-type asteroid 162173 Ryugu, seen by the ONC-T camera on board of Hayabusa2.
Source – ISAS/JAXA, CC SA 4.0.
Organic molecules have been detected in samples collected by Japan’s 2019 Hayabusa2 mission from the near-Earth asteroid Ryugu.
Ryugu is a carbon-rich, diamond-shaped asteroid that measures about 3,000 feet (1 kilometer) wide. Hayabusa2 was the first mission to return a subsurface sample from an asteroid to Earth.
During the Hayabusa2 mission, samples were collected from two different locations on the asteroid. The Ryugu samples, which looked like dark-gray rubble, were transported 155 million miles (250 million kilometers) back to Earth in a sealed capsule that landed in 2020 in Australia’s remote outback, according to CTV News Canada.
In a new research paper published in Nature Communications on Tuesday, scientists detailed their findings of uracil, one of the building blocks of RNA, as well as vitamin B3, or niacin (a key cofactor for metabolism in living organisms).
“Scientists have previously found nucleobases and vitamins in certain carbon-rich meteorites, but there was always the question of contamination by exposure to the Earth’s environment,” said lead study author Yasuhiro Oba, associate professor at Hokkaido University in Japan, in a statement, reports CNN News.
“Since the Hayabusa2 spacecraft collected two samples directly from asteroid Ryugu and delivered them to Earth in sealed capsules, contamination can be ruled out.”
Scientists long have wondered about the conditions necessary for life to arise after Earth formed about 4.5 billion years ago.
However, the new findings fit well with the hypothesis that bodies like comets, asteroids, and meteorites that bombarded early Earth seeded the young planet with compounds that helped pave the way for the first microbes.