Bennu Asteroid Samples Reveal Ribose and Glucose, Confirming Chemical Foundations for Life

An international team of scientists, including researchers from NASA and Japan, has unveiled groundbreaking findings following the analysis of samples retrieved from asteroid Bennu by the OSIRIS-REx mission. The data, formally presented on December 2, 2025, across publications in Nature Geoscience and Nature Astronomy, definitively confirms the presence of ribose and glucose within the deep-space material. These sugars are recognized as fundamentally critical components for terrestrial biology.

This discovery marks the first time that ribose, a structural building block of RNA, and glucose, the primary energy substrate utilized by Earth-based organisms, have been identified in extraterrestrial samples. The implications for understanding prebiotic chemistry within the early Solar System are substantial. While researchers caution that these findings do not constitute proof of extraterrestrial life, they powerfully illustrate the widespread availability of life’s chemical precursors throughout space.

The identification of ribose in the Bennu samples, alongside previously confirmed amino acids, nucleobases, and phosphates, paints a much clearer picture of the necessary components required for synthesizing RNA. This chemical inventory suggests that the raw materials for life’s fundamental machinery were readily available beyond Earth.

Interestingly, deoxyribose, the sugar essential for DNA structure, was notably absent from the analyzed material. This absence lends indirect support to the long-standing 'RNA World' hypothesis, which posits that RNA served as the primary genetic information carrier before the evolution of DNA in the genesis of life. The precious samples were brought back to Earth aboard the OSIRIS-REx spacecraft on September 24, 2023. Since their arrival, they have been meticulously preserved under ultra-clean conditions, utilizing high-purity nitrogen at NASA's Johnson Space Center to rigorously exclude any possibility of terrestrial contamination.

A parallel investigation uncovered a previously unseen polymer-like substance within the astronaut material. This substance, rich in both nitrogen and oxygen, has been provisionally dubbed 'cosmic resin' by the scientific team. Initially noted for its soft and elastic properties, the material has since hardened and is composed of intricate molecular chains. Researchers speculate that this substance could represent another vital chemical precursor to life. Its composition bears some resemblance to polyurethanes, yet it displays a more disordered structure, suggesting it formed under the unique environmental pressures present in a protoplanetary disk.

The third major revelation concerns the composition of dust that predates the formation of our Solar System. Analysis indicated that Bennu’s parent body contained six times more 'presolar grains'—dust originating from supernova explosions—than any other known cosmic material. This extraordinary abundance suggests that the matter which coalesced to form Bennu traversed a region subjected to intense cosmic radiation. These ancient particles offer direct, tangible evidence of processes operating in the interstellar medium long before our Sun even ignited.

Taken together, these three significant findings—the presence of essential sugars, the discovery of a complex polymer, and the record-breaking quantity of pre-solar dust—underscore that asteroids like Bennu function as true 'time capsules.' They have effectively preserved the chemical ingredients and environmental conditions of the nascent Solar System. Scientists, including lead group member Yoshihiro Furukawa from Tohoku University, hypothesize that carbonaceous asteroids of this type may have delivered all the necessary organic components required to initiate abiogenesis on the young Earth. The OSIRIS-REx mission, which launched on September 8, 2016, continues to yield unprecedented insights for the fields of astrobiology and planetary science.