Seeds from the Stars: Important New Insights on How Life May Have Started on Earth
Today’s posting offers an article by David H. Barad, MD, MS, a Director of Clinical ART and Senior Scientist at the Center for Human Reproduction. In a recent lecture he attended at the Lamont-Doherty Earth Observatory of Columbia Climate School in Palisades, New York, he learned about some valuable discoveries and research that may eventually help explain how life started on Earth. Though the article mainly addresses Earth and space-related science, arguably nothing is more relevant to reproductive biology than how life started in the first place. As always, we are welcoming comments and further discussion from our readers.
The CHR’s Editorial Staff
Seeds from the Stars: Important New Insights on How Life May Have Started on Earth
By David H. Barad, MD, MS, one of the CHR’s REI physicians, Associate Editor of CHR Publications, Director Clinical IVF, Director of CHR-Research and a Senior Scientist. He can be reached through the editorial office of the CHRVOICE and The Reproductive Times.
On a cool evening in late April, I had the pleasure of attending a lecture at the Lamont-Doherty Earth Observatory of Columbia Climate School in Palisades, New York. Founded in 1949 and perched atop the scenic Palisades overlooking the Hudson River, the Observatory has long been a leader in the world of Earth sciences. The talk was part of a free public lecture series hosted on site.
The speaker, Senior Research Scientist Kerstin A. Lehnert, PhD, presented “NASA’s Billion $$$ Samples: Space Rocks, Open Science, and the Era of AI.” Her lecture focused on extraterrestrial materials returned to Earth through NASA missions. Dr. Lehnert and her team have played a central role in cataloging these samples and maintaining a comprehensive, publicly accessible database that integrates both the materials themselves, and the growing body of research derived from them.
Midway through her fascinating lecture, she turned to the OSIRIS-REx mission to the near-Earth asteroid 101955 Bennu. This NASA-led mission was designed to collect and return pristine samples in order to better understand early solar system formation and the origins of life.
Launched in September 2016, the spacecraft arrived at Bennu in December 2018, where it conducted detailed mapping and compositional analysis using advanced imaging and spectroscopic instruments. In October 2020, it executed a brief touch-and-go maneuver, successfully collecting more than 70 grams of material—exceeding its target.
On its return, as the spacecraft approached Earth in September 2023, it released a small sample-return capsule that parachuted into the Utah Test and Training Range, while the spacecraft itself continued onward on an extended mission to another asteroid.
The most striking aspect of the returned 101955 Bennu samples was the richness of their organic chemistry. Early analyses identified carbon-containing compounds, nitrogen-bearing molecules, water-bearing clay minerals, and several classes of compounds considered important to prebiotic chemistry. In space science, the term “prebiotic” refers to “Complex Organic Molecules” (COMs): molecules that are not themselves alive, but that serve as the chemical precursors to life. These compounds represent the raw ingredients—the “recipe”—from which essential biological structures such as DNA, RNA, proteins, and cellular membranes can eventually arise.
Scientists detected amino acids, nucleobase-related compounds, and simple sugars in the Bennu samples, molecules that on Earth play central roles in biology. Importantly, these materials were recovered directly from space and returned under carefully controlled conditions, minimizing terrestrial contamination and making the findings especially compelling.
Researchers emphasized that these discoveries do not represent evidence of life itself, but rather evidence that the chemical building blocks associated with life can arise through entirely abiotic processes. This distinction is important. In chemistry, “organic” simply refers to carbon-based molecules and does not imply a biological origin. The Bennu samples support the growing understanding that complex organic chemistry may be a natural consequence of planetary and interstellar processes, rather than something unique to Earth. Primitive asteroids such as Bennu appear capable of acting as long-term reservoirs, preserving materials formed during the earliest history of the solar system.
These findings are further supported by observations from the James Webb Space Telescope (JWST), which has recently revealed what many scientists describe as a “treasure trove” of prebiotic chemistry throughout the universe. Using its Mid-Infrared Instrument (MIRI), JWST identified multiple complex organic molecules frozen within icy grains surrounding the young star ST6 in the Large Magellanic Cloud. These included ethanol, acetic acid, methanol, acetaldehyde, and methyl format—molecules considered important intermediates in the formation of amino acids and nucleotides.
Remarkably, this represented the first detection of several such “prebiotic seeds” as ices outside the Milky Way. JWST has also identified rich organic chemistry within heavily obscured galactic cores, including the first detection beyond our galaxy of the highly reactive methyl radical (CH3), an important intermediate in organic synthesis pathways.
In addition, JWST has detected polycyclic aromatic hydrocarbons (PAHs)—large, carbon-based molecules composed of fused aromatic rings—in galaxies more than 12 billion light-years away. These observations suggest that the universe was capable of producing chemically sophisticated organic compounds only about 1.5 billion years after the Big Bang. Together, the Bennu samples and JWST observations support a profound shift in perspective: the ingredients associated with life may not be rare or uniquely terrestrial but instead may emerge naturally wherever suitable physical and chemical conditions exist.
Equally important was the evidence of water-related chemistry within Bennu’s parent body. The presence of hydrated minerals suggests that the asteroid, or the larger body from which it originated, once interacted extensively with liquid water. Such environments are thought to facilitate complex chemical reactions, potentially allowing simple compounds to evolve into more sophisticated prebiotic molecules. This has strengthened scientific interest in the possibility that asteroids and comets may have delivered not only water to the early Earth, but also a rich inventory of organic materials that contributed to the emergence of life.
Taken together, these discoveries invite a profound reconsideration of humanity’s oldest question: how life began. The early Earth may not have been an isolated cradle struggling to invent biology from nothing, but rather a chemically fertile world repeatedly enriched by material arriving from space. One can imagine the young planet as a receptive and dynamic environment—oceans, minerals, atmosphere, lightning, and volcanic energy interacting with a continual rain of carbon-rich asteroids and comets carrying the molecular seeds of complexity.
In this view, bodies such as 101955 Bennu were not just inert rocks drifting through space, but cosmic couriers delivering the ingredients from which biology could eventually emerge. Whether life itself is common or exceedingly rare remains unknown, but missions such as the OSIRIS-REx mission and observations from the James Webb Space Telescope suggest that the chemistry leading toward life may be woven deeply into the fabric of the universe itself.