Asteroid Bennu Samples Reveal Ingredients for Life on Earth

Asteroid Bennu has emerged as a significant source of insights into the building blocks of life, following the analysis of samples brought back to Earth by NASA's OSIRIS-REx mission. Recent findings confirm that all essential ingredients for life as we know it have been identified in the Bennu samples.

According to New Scientist, the mission, which collected samples from Bennu in 2020 and returned them in 2023, revealed that the asteroid contains water, carbon, organic molecules, amino acids, formaldehyde, and the five nucleobases found in RNA and DNA.

Most notably, researchers have now identified ribose, a five-carbon sugar, as well as other sugars like glucose, in the Bennu samples, which was previously unconfirmed in extraterrestrial materials. Yoshihiro Furukawa from Tohoku University led the study that detected these bio-essential sugars through gas chromatography-mass spectrometry, marking a pivotal moment in understanding the molecular ingredients required for life.

This discovery supports the RNA world hypothesis, indicating that ribose may have been more prevalent than deoxyribose in the early solar system, which aligns with the theory that early life forms relied primarily on RNA.

Furukawa noted this finding guarantees the results were not a product of contamination, as had been a concern with previous findings in Earth meteorites. NASA's analysis also identified a gum-like substance not seen before in astromaterials, described by Scott Sandford of NASA's Ames Research Center.

This ancient material, rich in nitrogen and oxygen, is thought to have formed in the early solar system as Bennu's parent asteroid warmed. This gum could have provided chemical precursors pivotal for life.

Additionally, researchers found an unexpectedly high abundance of dust from supernovae in Bennu's samples, indicating that the asteroid's parent body was formed in a region enriched with materials from dying stars.

These findings collectively enhance our understanding of how asteroids like Bennu may have delivered the essential ingredients for life to early Earth, and possibly to other celestial bodies. The ongoing analysis of Bennu's samples continues to unravel the complexities of life's origins and the potential for extraterrestrial life, with implications that could reshape our understanding of biology across the universe.