5.5-billion-year-old meteorite reveals tens of thousands of molecules from early solar system

Scientists have taken an unusually detailed look at the organic chemistry preserved inside two meteorites, revealing tens of thousands of carbon-based molecules and, for the first time in this study, images showing the structures of individual molecules. The research brought together scientists from the National High Magnetic Field Laboratory (MagLab), Florida State University, and Brookhaven National Laboratory. Using the MagLab’s ultra-high-resolution mass spectrometer and Brookhaven’s atomic-scale microscopy, the team examined fragments of the Murchison meteorite, which fell in Australia in 1969, and the Aguas Zarcas meteorite, which fell in Costa Rica in 2019. The findings were published in The Planetary Science Journal. Reading the chemistry preserved in ancient rocks Meteorites can act as chemical time capsules, preserving material from the period when the solar system was forming. Murchison is particularly valuable because it is a carbonaceous chondrite containing abundant organic material and has been studied extensively since its fall. The new analysis used the MagLab’s 21-tesla Fourier-transform ion cyclotron resonance (FT-ICR) mass spectrometer, which can distinguish an enormous number of compounds within extremely complex mixtures. Researchers dissolved tiny pieces of the meteorites in organic solvents before analyzing them. The technique revealed tens of thousands of carbon-based molecular compositions in small samples of each meteorite. That number does not mean scientists identified tens of thousands of completely unique molecular structures. Mass spectrometry primarily reveals the molecular formulas present, and different molecular structures can share the same formula. This is where the Brookhaven contribution became important. From chemical formulas to molecular structures Brookhaven scientist Percy Zahl used high-resolution, noncontact atomic force microscopy to examine individual molecules from the meteorite material. The technique uses an extremely sharp probe positioned above a surface. Rather than physically touching the molecule, the microscope measures interactions between the probe and the material to image its structure. Knowing a molecule’s elemental composition does not necessarily reveal how its atoms are connected. Different arrangements can produce molecules with the same chemical formula but different structures. The researchers said successfully imaging individual molecules in such a complex mixture can require anywhere from days to months of painstaking work. The study is only the third reported use of this type of microscopy on meteorite material, the research team said. The combination effectively gives scientists two complementary views: mass spectrometry provides a broad chemical inventory, while microscopy can reveal the architecture of selected molecules. Two meteorites, very different chemistry The comparison between Murchison and Aguas Zarcas produced another important result. Although both meteorites belong to the same broad family of carbon-rich meteorites and can look similar, their molecular fingerprints were substantially different. Only a relatively small fraction of their complex molecular compositions overlapped. That suggests the parent asteroids from which these materials came experienced different chemical environments during their formation and subsequent evolution. The result adds to evidence that the early solar system was not chemically uniform. Asteroids could undergo different combinations of heating, alteration, water-driven reactions, and other processes, leaving distinct chemical signatures in the material eventually delivered to Earth. Murchison itself is especially ancient. The researchers describe it as at least 5.5 billion years old, making it older than Earth and providing a window into material that predates the formation of our planet. What does this mean for the origins of life? The discovery does not show that life, or even the direct precursor to life, came from these meteorites. Instead, it demonstrates how chemically rich extraterrestrial material can be. Organic compounds are widespread in meteorites, and some meteorites preserve material that existed before or during the earliest stages of solar-system formation. Murchison has previously yielded evidence of presolar grains, tiny pieces of material that formed before the Sun and survived inside the meteorite. The Field Museum, which houses a major portion of the Murchison meteorite, describes it as one of the most extensively studied carbonaceous chondrites. The new work pushes that investigation toward something more precise: not simply asking which elements and molecules survived, but beginning to determine what individual extraterrestrial molecules actually look like.That combination of chemical mapping and molecular imaging could give researchers a more detailed picture of the organic inventory available in the early solar system, and help scientists better understand the chemical starting conditions from which planets, and eventually life, emerged.Get the latest in engineering, tech, space & science - delivered daily to your inbox.Kaif Shaikh is a journalist and writer passionate about turning complex information into clear, impactful stories. His writing covers technology, sustainability, geopolitics, and occasionally fiction. A graduate in Journalism and Mass Communication, his work has appeared in the Times of India and beyond. After a near-fatal experience, Kaif began seeing both stories and silences differently. Outside work, he juggles far too many projects and passions, but always makes time to read, reflect, and hold onto the thread of wonder.