Life’s Building Blocks Found in Ryugu Asteroid Sample | CNBC Indonesia

Building Blocks of Life Found in Asteroid Ryugu Sample

Tokyo, Japan – An international team of researchers has confirmed the presence of uracil, one of the nucleobases that make up RNA and DNA, in a sample collected from the asteroid Ryugu and returned to Earth in 2020. The discovery, confirmed in 2026, adds to previous findings of organic molecules in meteorites and strengthens the theory that the building blocks of life could have been delivered to Earth from space.

The sample, weighing 5.4 grams, was obtained by Japan’s Hayabusa2 mission, which rendezvoused with the near-Earth asteroid Ryugu in June 2018, according to NASA’s Ares mission page. Hayabusa2 successfully collected carbonaceous samples and returned them to Earth on December 6, 2020. The analysis focused on two samples of roughly equal size.

While nucleobases have previously been detected in meteorites that fell to Earth – notably the Murchison meteorite in Australia (1969) and the Orgueil meteorite in France (1864) – those findings have been subject to debate due to the potential for terrestrial contamination during the meteorites’ descent and subsequent handling. Earthsky notes that the possibility of contamination makes it tricky to definitively determine if the nucleobases originated in space.

Ryugu, however, offers a pristine sample. As a near-Earth object, Ryugu is classified as a Cb-type asteroid, characterized by a dark surface and a diameter of approximately 1 kilometer. It is believed to be rich in water and carbonaceous materials, key elements for the emergence of life. The Hayabusa2 mission delivered the sample directly from space, minimizing the risk of contamination.

The research suggests that the components of genetic material may have formed in space and been subsequently delivered to Earth, implying a connection between the chemistry of asteroids and the origins of life on our planet.

Ryugu’s orbital history as well provides clues to its composition. Analysis of surface features revealed that the asteroid underwent a period of close proximity to the sun, resulting in a “sunburned” effect on its surface, as reported by JAXA. This solar heating altered the surface material, creating a distinction between reddish and blue hues observed by the Hayabusa2 spacecraft during its landing in February 2019. The study, published in Science in May 2020, indicated that the red, fine-grained material was produced by solar heating, suggesting that Ryugu’s surface has been weathered by the sun over time.

The discovery of uracil in the Ryugu sample is part of an ongoing collaboration between NASA and JAXA. Ten percent of the regolith collected by Hayabusa2 is being curated at NASA’s Astromaterials curation facility, where a dedicated clean laboratory has been constructed for its analysis. Scientists are developing specialized tools and procedures to handle the small particles without compromising their scientific integrity, with the goal of making the samples available to researchers worldwide.