Scientists have discovered that meteorites, specifically unmelted asteroids, may have played a key role in bringing the essential ingredients for life to Earth.
Researchers from the University of Cambridge and Imperial College London have used the chemical fingerprints of zinc found in meteorites to understand how Earth got its supply of volatile elements – materials that easily change into gas and are essential for life, including water.
Volatile elements, such as those found in living organisms, are critical for life to exist.
By studying the zinc in meteorites, researchers were able to trace the origin of these elements.
Their findings suggest that without certain types of meteorites, Earth might not have received enough of these life-supporting compounds to allow life to emerge.
The team found that Earth’s zinc came from different parts of the solar system.
About half of it came from areas far beyond Jupiter, and the other half from closer regions.
This research helps answer one of the biggest questions about the origin of life: where did the materials necessary for life to develop come from?
The building blocks of planets, known as planetesimals, are small objects that stick together during the early stages of a solar system’s formation.
However, not all planetesimals are alike. Some of them, called “melted” planetesimals, were exposed to high levels of radiation, causing them to lose their volatile elements.
Others, known as “unmelted” planetesimals, formed later and were able to keep more of these essential materials.
In the study, the researchers analyzed a large sample of meteorites from different planetesimals. They found that while the melted planetesimals contributed about 70% of Earth’s overall mass, they only provided 10% of its zinc.
The remaining zinc came from unmelted, primitive materials, which were crucial for delivering the volatile elements needed for life.
The findings show that having the right materials, like water and volatiles, is not guaranteed for planets, even if they are in the right position to support life.
This research could help in the search for life on other planets, as it gives scientists more clues about what to look for when searching for habitable worlds beyond our solar system.
