New Research Reveals Mars as a Significant Source of Meteorites Hitting Earth
Meteorites striking Earth is a phenomenon as old as time. While some of these space rocks originate from distant corners of the universe, many come from much closer to home—Mars. Recent scientific findings have revealed that hundreds of meteorites that have hit Earth in recent years have originated from just five specific impact craters on Mars.
Martian meteorites: A new understanding
Severe impact events on Mars have sent debris hurtling into space, some of which eventually reached Earth. According to researchers, at least ten significant meteorite-forming events have occurred on Mars in the recent past. These events release debris that escapes Mars’ gravitational pull, entering orbit around the sun before eventually colliding with Earth.
“Now, we can group these meteorites by their shared history and then their location on the surface before coming to Earth,” said Chris Herd, co-author of the study, professor of earth and atmospheric sciences, and curator of the University of Alberta’s Meteorite Collection.
Tracing the Meteorites’ Origins
Over the years, scientists have discovered hundreds of Martian meteorites, with around 200 of them traced back to five specific craters on the Red Planet. The University of Alberta researchers have pinpointed their origins to two major volcanic regions on Mars: Tharsis and Elysium. These findings suggest that these regions have played a significant role in the generation of Martian meteorites that have impacted Earth.
NASA estimates that Earth is bombarded with approximately 48.5 tonnes of meteorite material each day. However, studying these materials is often challenging because many of them are reduced to mere specks of dust by the time they reach Earth’s surface.
A breakthrough in meteorite research
The journey to understanding the origins of Martian meteorites began in the 1980s when scientists identified a group of meteorites with volcanic origins dating back 1.3 billion years. The volcanic nature of these rocks pointed to Mars as their likely source. This was confirmed when NASA’s Viking landers compared Mars’ atmospheric composition with trapped gases found in these meteorites.
However, tracing the precise origins of these meteorites had long been challenging due to the limitations of a technique called spectral matching. This method, which identifies and compares materials by analyzing light absorption and emission patterns, was hindered by Mars’ terrain variability and extensive dust cover.
Herd emphasized that the recent findings represent a “major advance” in meteorite research, allowing scientists to refine previous calculations. “I call that the missing link—to be able to say, for example, the conditions under which this meteorite was ejected were met by an impact event that produced craters between 10 and 30 kilometers across,” he said.
Implications for Mars’ Geological History
The new research offers a deeper understanding of Mars’ geological past, shedding light on the planet’s volcanic activity and impact history. By tracing the origins of these meteorites, scientists hope to uncover more about the conditions and events that shaped Mars’ surface, offering valuable insights into our neighboring planet’s history.