NASA Confirms 'Asteroid Bennu' Samples Contain Extraterrestrial Building Blocks of Life

NASA’s OSIRIS-REx mission has delivered groundbreaking insights into the origins of life, thanks to pristine samples collected from the asteroid Bennu.

The findings, published in Nature Astronomy and other journals, reveal that Bennu contains the essential building blocks of life, including amino acids and nucleobases—key components of proteins, DNA, and RNA.

This discovery suggests that the conditions necessary for life may have been widespread across the early solar system, raising tantalizing questions about the potential for life beyond Earth.

The mission, which returned 120 grams of material (about the weight of a banana) to Earth in 2023, marks the first time the U.S. has conducted such an in-depth analysis of extraterrestrial samples. Initial studies confirmed the presence of high-carbon content and water, but the latest research goes further.

Scientists found that Bennu’s parent asteroid once harbored liquid water, which evaporated and left behind a “briny broth” of salts and minerals. These compounds, some never before seen in space samples, provide “the raw ingredients of life,” according to Tim McCoy, curator of meteorites at the Smithsonian National Museum of Natural History and co-lead author of one of the studies.

The samples also contained 14 of the 20 amino acids used to create proteins on Earth, alongside ammonia and formaldehyde—chemicals that react to form amino acids. This suggests that complex organic molecules could have formed naturally in the early solar system. “This is rewriting everything we know,” said Nicky Fox, head of NASA’s Science Mission Directorate.

The pristine nature of the Bennu samples is crucial. Daniel Glavin of NASA noted, “The clues we’re finding are incredibly fragile and could never survive Earth’s contamination.” This ensures that the organic molecules detected are genuinely extraterrestrial, not contaminants from Earth.

The findings also hint at Bennu’s history as a “water world,” with minerals like calcite, halite, and sylvite indicating the presence of liquid water during its formation 4.5 billion years ago. “These processes probably occurred much earlier and were much more widespread than we had thought before,” McCoy added.

This discovery fuels speculation about life elsewhere in the solar system. Could icy bodies like Europa or Enceladus, or even the dwarf planet Ceres, host similar briny environments? “Even though asteroid Bennu has no life, the question is could other icy bodies harbor life?” said Nick Timms of Curtin University.

While the findings don’t confirm extraterrestrial life, they provide compelling evidence that the ingredients for life are not unique to Earth.

As Sara Russell, a cosmic mineralogist at the Smithsonian, put it, the research has made “huge progress in understanding how asteroids like Bennu evolved, and how they may have helped make the Earth habitable.”

The age-old question remains: Are we alone in the universe? Bennu’s secrets suggest the answer might be written in the stars.