Asteroid Bennu rocks sugar discovery guym substance early solar system

Recent studies of asteroid Bennu samples, returned to Earth by NASA’s OSIRIS-REx mission, have revealed surprising compounds that could inform our understanding of the early solar system and the origins of life.
Published Tuesday in Nature Geosciences and Nature Astronomy, the findings include sugars vital for biology and a gum-like substance not previously observed in astromaterials. These discoveries provide scientists with new perspectives on the potential delivery of life's building blocks to early Earth.
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A research team led by Yoshihiro Furukawa of Tohoku University identified ribose, a five-carbon sugar crucial for RNA, and, for the first time in an extraterrestrial sample, glucose, a six-carbon sugar essential for energy in living cells. Their presence, alongside previously detected amino acids and nucleobases in Bennu material, suggests these components may have been widespread in the early solar system.
Ribose and deoxyribose are central to the structure of RNA and DNA, respectively. In living organisms, DNA stores genetic information, while RNA is involved in various biological processes. The detection of ribose, but not deoxyribose, in the samples is notable. According to the research, this may mean ribose was more common in early solar system environments.
“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,” said Furukawa. “The new discovery of ribose means that all of the components to form the molecule RNA are present in Bennu.”
Scientists believe that the presence of ribose, combined with the absence of deoxyribose, supports the “RNA world” hypothesis, which posits that RNA played a central role in the earliest forms of life. This finding, combined with the detection of glucose, suggests that basic energy sources for life existed in the early solar system as well.
Ribose and glucose are sugars essential to life on Earth. RNA uses ribose for its structure. Glucose provides cells with energy and is used to make fibers like cellulose.
Alongside these sugars, a team led by Scott Sandford at NASA’s Ames Research Center and Zack Gainsforth at the University of California, Berkeley, identified a gum-like material in Bennu rocks never previously seen in space samples.
This nitrogen- and oxygen-rich polymer may represent early chemical processes that contributed to life’s emergence.
“With this strange substance, we’re looking at, quite possibly, one of the earliest alterations of materials that occurred in this rock,” said Sandford. “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.”
Sandford also described his team’s methods as “blacksmithing at the molecular level” to analyse these carbon-rich grains.
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