Scientists Link 3.5 Billion-Year-Old Asteroid Strike To Dawn Of Life On Earth

by Aaron Leong — Friday, June 12, 2026, 11:18 AM EDT

A small stone discovered in the sands of Mali is reimagining what we know about the early solar system. By examining this rare lunar meteorite, planetary scientists have mapped out a sequence of cosmic collisions that retell the history shared by Earth and the Moon.

Thanks (or no thanks) to plate tectonics, erosion, and volcanic activity on Earth, finding pristine physical evidence of what happened here billions of years ago is nearly impossible. To uncover our planet's earliest chapters, scientists must sometimes look to the Moon, a geologically quiet place where the lack of an atmosphere or weather acts as a permanent cosmic museum.

lm nwa 12593 6445 dustin dickens 1920 — *Two views of Northwest Africa 12593. (Credit: Washington University in St. Louis)*

The meteorite, called Northwest Africa (NWA) 12593, is a lunar breccia, essentially a natural concrete formed when fragments of different rocks are fused together by extreme force. A research team at the University of Colorado Boulder subjected the stone to radiometric dating and chemical analysis, revealing that it survived three distinct impacts. The last collision launched it off the Moon toward Earth, while a prior mid-history strike smashed and welded the fragments into its current concrete-like form.

However, it is the first and oldest impact that is the most interesting. Dated to roughly 3.5 billion years ago, this colossal asteroid strike released enough energy to turn the lunar surface into a sheet of liquid rock. The heat was so intense that it generated cubic zirconia, a mineral that requires extreme, controlled temperatures to form. Though the mineral fragilely dissolved as the magma cooled, researchers successfully identified its chemical fingerprints locked inside the meteorite.

scientists discover a 7 — *Electron backscatter diffraction data of NWA 12593 baddeleyite (grain C 13) with cubic parent. (Credit: Geology)*

This 3.5-billion-year-old timestamp coincidentally mirrors known impact records found in ancient crusts on Earth, as well as on 4 Vesta, one of the largest objects in the asteroid belt. Finding an identical bombardment signature across three completely separate bodies suggests a coordinated, system-wide event. This possibly indicates that the inner solar system was transitioning away from the constant chaos of planet formation toward a sudden, massive wave of debris, perhaps caused by the breakup of a giant asteroid.

It is curious that on Earth, the earliest fossil evidence of microbial life appears around 3.5 billion years ago, isn't it? One one hand, such extreme impacts are usually viewed as destructive forces capable of sterilizing whole environments, whereas on the other, other models show a dual nature to these events.

In this scenario, hypervelocity impacts fractured the early terrestrial crust, plowing up the surface and generating highly permeable channels. When coupled with Earth's internal heat, these fractured zones created extensive underground hydrothermal systems (a la the geyser networks in Yellowstone National Park). Water circulating through these hot, mineral-rich environments could have provided the exact chemical means and energy sources needed for early life to take root and evolve.

Main image: XRF map of 7.53 g slice of NWA 12593: calcium (Ca) and iron (Fe) (Credit: Crow et al)