For decades, scientists have wondered whether the raw ingredients for life might have arrived on Earth aboard ancient space rocks. Now, an international team of researchers has delivered compelling new evidence: pristine samples from asteroid Bennu contain not just one but several bio-essential sugars, including ribose—the backbone of RNA—and glucose, the universal fuel of living cells. The discovery, published this week in Nature Geoscience, represents the first confirmed detection of glucose in any extraterrestrial material and completes the molecular inventory needed to construct RNA from asteroidal sources.

The findings emerge from NASA’s OSIRIS-REx mission, which spent seven years traveling to Bennu, collecting samples, and returning them safely to Earth in September 2023. Unlike meteorites that crash through our atmosphere and become contaminated by terrestrial organisms, these 121.6 grams of asteroid material have been meticulously protected from biological exposure. This pristine quality has allowed researchers to probe Bennu’s chemistry with unprecedented confidence.

“All five nucleobases used to construct both DNA and RNA, along with phosphates, have already been found in the Bennu samples brought to Earth by OSIRIS-REx,” says Yoshihiro Furukawa from Tohoku University. “The new discovery of ribose means that all of the components to form the molecule RNA are present in Bennu.”

Lead researcher Yoshihiro Furukawa and his colleagues at Tohoku University in Japan identified all four aldopentoses—ribose, lyxose, xylose, and arabinose—as well as glucose and galactose in a 603-milligram sample of homogenized Bennu powder. Using sophisticated gas chromatography-mass spectrometry techniques, the team carefully distinguished these sugars from potential contaminants, confirming their extraterrestrial origin through rigorous procedural blanks.

The significance of finding ribose cannot be overstated. This five-carbon sugar forms the structural backbone of RNA, linking together the nucleobases that carry genetic information. Previous analyses of Bennu samples had already revealed all five nucleobases found in DNA and RNA—adenine, guanine, cytosine, thymine, and uracil—along with phosphate. With ribose now added to the list, every molecular component necessary to assemble RNA exists within this 4.5-billion-year-old asteroid.

Perhaps equally intriguing is what researchers did not find: 2-deoxyribose, the sugar that forms the backbone of DNA. This absence carries profound implications for understanding life’s earliest chemistry. The RNA world hypothesis, first proposed in the 1960s and refined over subsequent decades, suggests that RNA preceded DNA as the primary carrier of genetic information. RNA’s unique ability to both store genetic data and catalyze chemical reactions—a dual function that neither DNA nor proteins can accomplish alone—makes it a prime candidate for the original molecule of life.

According to scientist, Yoshihiro Furukawa, “Present day life is based on a complex system organized primarily by three types of functional biopolymers: DNA, RNA, and proteins. However, early life may have been simpler. RNA is the leading candidate for the first functional biopolymer because it can store genetic information and catalyze many biological reactions.”

The detection of glucose adds another dimension to the discovery. While ribose captures attention for its role in genetics, glucose serves as life’s most fundamental energy currency. Nearly all organisms on Earth—from ancient anaerobic bacteria to complex mammals—rely on glycolysis, the metabolic breakdown of glucose, to power cellular functions. Finding this sugar in Bennu suggests that not only the informational molecules but also the energy sources for primitive metabolism were present in the early solar system.

The Bennu findings slot into a growing body of evidence that asteroids carried the molecular precursors of life throughout our solar system. Earlier this year, researchers announced that Bennu samples contained 14 of the 20 amino acids used by terrestrial life to build proteins, along with remarkably high concentrations of ammonia. Just last week, a separate analysis tentatively identified traces of tryptophan—an essential amino acid never before definitively found in extraterrestrial material—bringing the tally to 15 out of 20 protein-building amino acids.

These discoveries transform our understanding of what the early solar system contained. Bennu likely originated from a larger parent asteroid that formed in the cold outer reaches of the solar system, beyond Saturn’s orbit, where ices and organic compounds could accumulate. At some point, this parent body warmed enough for liquid water to percolate through its interior, driving chemical reactions that produced the diverse organic molecules now found in Bennu’s regolith.

The researchers propose that Bennu’s sugars formed through the formose reaction, a process in which formaldehyde molecules combine to create increasingly complex sugars. Formaldehyde has been detected both in interstellar space and in Bennu samples themselves. When this simple compound reacts in the presence of alkaline fluids and divalent metal ions like calcium and magnesium—both abundant in Bennu—it can generate ribose and other sugars. The slightly alkaline pH measured in Bennu extracts, around 8.23, supports this formation pathway.

Ribose, however, is not a particularly stable molecule. Its relatively high abundance in Bennu, comparable to that in the well-studied Murchison meteorite, puzzled researchers initially. Laboratory simulations suggest that under certain conditions—particularly longer-duration reactions at elevated temperatures with calcium catalysts—ribose can form efficiently alongside other pentoses. The sugar distribution in Bennu closely matches these experimental products, indicating that the same abiotic chemistry that scientists recreate in laboratories occurred naturally within Bennu’s parent asteroid billions of years ago.

The absence of 2-deoxyribose tells its own story. This DNA sugar possesses more than two orders of magnitude higher chemical reactivity than the sugars detected in Bennu. If 2-deoxyribose ever formed in the parent asteroid, subsequent aqueous reactions likely consumed it long before the material reached Earth. This differential survival of ribose over deoxyribose in asteroidal environments provides additional support for theories that RNA-based life preceded DNA-based life.

This week’s publications included additional surprises from Bennu. A separate paper in Nature Astronomy describes a never-before-seen “space gum”—a flexible, polymer-like material rich in nitrogen and oxygen that formed in the earliest days of the solar system. This ancient substance, which researchers compare to a kind of space plastic, could have provided chemical precursors that helped trigger life on Earth. Another study revealed that Bennu contains six times more supernova dust than any previously studied astromaterial, hinting at the asteroid’s origins in a region of the protoplanetary disk enriched by the remnants of dying stars.

According to Scott Sandford, NASA Ames Research Center, “With this strange substance, we’re looking at, quite possibly, one of the earliest alterations of materials that occurred in this rock. On this primitive asteroid that formed in the early days of the solar system, we’re looking at events near the beginning of the beginning.”

Together, these discoveries paint a picture of an early solar system teeming with the raw materials for life. Carbonaceous asteroids like Bennu’s parent body acted as chemical factories, concentrating organic molecules in their interiors and distributing them throughout the inner solar system through collisions and fragmentation. Earth, along with Mars and potentially other worlds, would have been showered with these building blocks during the period of heavy bombardment that characterized our solar system’s youth.

The implications extend beyond our own planet. Similar brines and organic-rich materials have been detected or inferred on the dwarf planet Ceres and Saturn’s moon Enceladus. If the molecular ingredients for life were common throughout the solar system four billion years ago, they may have seeded multiple environments where life could potentially arise.

“Data from OSIRIS-REx adds major brushstrokes to a picture of a solar system teeming with the potential for life,” noted Jason Dworkin, OSIRIS-REx project scientist at NASA Goddard. “Why we, so far, only see life on Earth and not elsewhere—that’s the truly tantalizing question.”

The majority of Bennu’s returned sample remains unstudied, carefully curated at NASA’s Johnson Space Center for future generations of scientists. Like the Apollo moon rocks before them, these asteroid fragments will continue yielding discoveries for decades to come. As analytical techniques improve and new questions arise, researchers will return to this precious material, extracting ever more secrets from the ancient rubble that once drifted silently between Mars and Jupiter.

For now, the sugar discovery completes a remarkable scientific narrative: all three fundamental building blocks of life—amino acids for proteins, nucleobases for genetic information, and sugars for both structure and energy—have been found together in the same pristine extraterrestrial sample. Whatever else remains unknown about life’s origins, we now know that the raw ingredients were available, scattered across the cosmos, waiting to fall to Earth.

Sources

1. Furukawa, Y. et al. “Bio-essential sugars in samples from asteroid Bennu.” Nature Geoscience (2025). https://doi.org/10.1038/s41561-025-01838-6
2. NASA. “Sugars, ‘Gum,’ Stardust Found in NASA’s Asteroid Bennu Samples.” NASA Press Release, December 2, 2025. https://www.nasa.gov/missions/osiris-rex/sugars-gum-stardust-found-in-nasas-asteroid-bennu-samples/
3. Glavin, D.P. et al. “Abundant ammonia and nitrogen-rich soluble organic matter in samples from asteroid (101955) Bennu.” Nature Astronomy (2025). https://doi.org/10.1038/s41550-024-02472-9
4. NASA. “NASA’s Asteroid Bennu Sample Reveals Mix of Life’s Ingredients.” NASA Press Release, January 29, 2025.
5. Sandford, S. et al. Nature Astronomy (2025). https://doi.org/10.1038/s41550-025-02694-5
6. NCBI Bookshelf. “The RNA World and the Origins of Life.” Molecular Biology of the Cell. https://www.ncbi.nlm.nih.gov/books/NBK26876/