Cosmic Chemistry and the Origins of Life: Prebiotic Molecules Born Among the Stars

In a story that reads more like science fiction than lab science, researchers at the University of Hawaiʻi at Mānoa have uncovered compelling evidence that life’s earliest ingredients may have formed not in Earth’s bubbling primordial soup—but far earlier, in the frigid, silent reaches of deep space. Their work suggests that the fundamental molecules driving life’s metabolic engine were synthesized in the dark voids between the stars—long before our planet even existed.

Published in the Proceedings of the National Academy of Sciences, this groundbreaking study from the W. M. Keck Research Laboratory in Astrochemistry explores how prebiotic molecules—specifically, a complete family of complex carboxylic acids essential to metabolism—can form under the extreme, life-less conditions of interstellar space. It’s a discovery that reshapes our understanding of how life might emerge not only on Earth, but throughout the cosmos.

Before Earth, There Was Chemistry

To understand just how revolutionary this discovery is, we need to first consider one of biology’s most important processes: metabolism. At the heart of metabolism is a chain of chemical reactions that convert food into usable energy. The central hub of this process is the Krebs cycle, also known as the citric acid cycle—a well-oiled biochemical engine that churns through organic acids to power nearly every living cell on Earth.

Now, imagine these same complex molecules—tricarboxylic acids like citric acid, succinic acid, and fumaric acid—existing long before any cell, ocean, or even planet had formed. That’s exactly what the Hawaiʻi researchers found.

Using a lab setup that mimics the brutal cold and radiation of deep interstellar clouds, the team showed that these organic acids could form in ice-coated grains of dust drifting in space. These are the same compounds detected in ancient meteorites like Murchison and Ryugu—celestial bodies that have crashed onto Earth bearing traces of carbon-rich, biologically interesting molecules.

A Simulation of the Stars, Made on Earth

How do you recreate the conditions of deep space in a terrestrial laboratory? The researchers turned to an environment that’s a stark contrast to the tropical paradise that surrounds them.

In their custom-built chamber, simple gases like carbon dioxide, water vapor, and methane were cooled to near absolute zero—just a few degrees above −273°C. At these ultracold temperatures, molecules behave more like statues than dancers. Then, using high-energy particles as stand-ins for galactic cosmic rays, the researchers bombarded the ices to mimic the relentless radiation that permeates interstellar clouds. Finally, they gently warmed the samples, echoing the thermal evolution of cosmic dust as stars ignite and planetary systems form.

This method produced not just one or two types of carboxylic acids—but a full set of them, including mono-, di-, and tricarboxylic acids, all essential components of the Krebs cycle. It’s as if nature had assembled a starter kit for biochemistry in deep space and left it in the care of comets and asteroids, waiting to be delivered to fertile worlds.

Meteorites as Molecular Time Capsules

The idea that organic molecules from space helped kickstart life on Earth isn’t entirely new. For decades, scientists have found amino acids, sugars, and even nucleobases (the building blocks of DNA) in meteorites. But this new study adds a critical missing piece: the carboxylic acids central to metabolism.

Carbon-rich meteorites like Murchison, which fell in Australia in 1969, have long fascinated researchers for their treasure troves of organic chemistry. Similarly, asteroid Ryugu, recently sampled and returned to Earth by Japan’s Hayabusa2 mission, showed clear signs of prebiotic compounds. These space rocks are relics of the early solar system—frozen records of what was drifting between the planets before Earth had even taken shape.

Now, thanks to the Hawaiʻi team, we have a mechanism by which those very molecules could have been forged in the interstellar medium. It’s an elegant explanation, linking the origins of life’s chemistry not just to the conditions of early Earth, but to the greater theater of star and planet formation itself.

The Cosmic Connection: Life as a Universal Phenomenon

If the building blocks of metabolism can be made in deep space, that has profound implications—not just for Earth’s past, but for the potential ubiquity of life throughout the universe.

Stars are born within dense molecular clouds, where temperatures plunge and radiation penetrates with ease. These regions are filled with icy dust grains that can host the same kinds of chemistry now demonstrated in the lab. As stars form, the surrounding material collapses into disks that give rise to planets. The icy bodies within those disks—comets, asteroids, and planetesimals—act as delivery systems, ferrying prebiotic molecules to emerging worlds.

This cosmic chemistry suggests that the seeds of life might be universal, sown on countless planets across the galaxy by the same processes that worked their magic billions of years ago in the cradle of our solar system.

Professor Ralf I. Kaiser, co-author of the study, put it succinctly: “This work shows that the basic ingredients for life’s chemistry could have been made in space, long before Earth even formed.”

Indeed, it paints a poetic picture—one in which life on Earth began not with a lightning bolt in a primordial pond, but with a whisper of radiation and a dusting of cosmic snow, drifting silently across interstellar space.

Hawaiʻi’s Hidden Role in the Search for Life

It may come as a surprise that such cutting-edge space research is happening in Hawaiʻi, more commonly associated with volcanoes and beaches than the birth of biology. Yet the islands are home to some of the most sophisticated astrochemical research in the world.

Lead author Mason McAnally, a graduate student in the Department of Chemistry, emphasized the global significance of the work. “The unique research happening in the islands puts Hawaiʻi at the forefront of astrobiology and space chemistry,” he said. And he’s right. Hawaiʻi’s position as a leader in astronomical observation—with the Maunakea Observatories—and in laboratory-based astrochemistry is helping rewrite our understanding of how life begins.

The Keck Laboratory’s approach combines the observational with the experimental. While telescopes peer into deep space to detect the faint signatures of molecules in faraway clouds, researchers like McAnally and Kaiser are recreating those same environments right here on Earth to test their hypotheses. It’s a feedback loop of discovery, bringing us closer to answering the age-old question: Are we alone?

New Frontiers: What Comes Next?

With this success, researchers are now setting their sights on expanding the list of cosmic molecules that may be involved in life’s origin. Could even more complex compounds—like those involved in DNA and RNA synthesis—form under similar conditions? Could lipid precursors, which form the membranes of cells, also be born in space?

There’s also growing interest in how these molecules survive the fiery journey through planetary atmospheres. How much of the cosmic cargo gets delivered intact? And how does it interact with early Earth environments like hydrothermal vents, tidal pools, or volcanic soils?

These questions are more than academic. They directly inform the search for life beyond Earth. Missions to icy moons like Europa and Enceladus, as well as rovers exploring Mars and sample-return efforts from asteroids, are all potential proving grounds for the theories being tested in labs like the one in Hawaiʻi.

The Stardust Within Us

In the grandest sense, this research brings us full circle. It validates the notion that we are made of stardust—not just in the poetic sense of Carl Sagan’s famous quote, but in the literal, chemical sense. The organic acids that course through your body, powering your every breath and heartbeat, may have once floated in the void between stars, waiting patiently for a chance to spark life.

This cosmic origin story elevates the quest for understanding life. It transforms it into a journey not just of biology or geology, but of astronomy and chemistry, intertwined. It reminds us that life’s emergence isn’t a miracle reserved for Earth—it may be a natural consequence of the universe itself.

In discovering how these molecules form, the University of Hawaiʻi team hasn’t just solved a puzzle—they’ve opened a door to a deeper truth: that life, in all its complexity, may be the inevitable result of physics and chemistry playing out across time and space.

And if that’s true, then perhaps the universe is not just a place where life can exist. Perhaps it’s a place where life wants to exist—where the chemistry of creation is written into the fabric of the stars themselves.

Reference: Mason McAnally et al, Abiotic origin of the citric acid cycle intermediates, Proceedings of the National Academy of Sciences (2025). DOI: 10.1073/pnas.2501839122