This August, new geochemical findings from an impact site in Chicxulub, Mexico have confirmed that it was the impact of an asteroid on earth which led to the mass extinction of the dinosaurs over 66 million years ago.
Since the 1980s it has been hypothesised that an asteroid was the cause of the mass extinction event, but these new findings published in Science have revealed the likely type of asteroid and its origins.
Mario Fischer-Gödde and his team took rock samples from the impact site in Mexico’s Yucatán Peninsula and compared them with rocks from eight other impact sites around the world, looking specifically at the presence of Ruthenium isotopes within them.
Looking at Ruthenium isotopes helped determine whether the asteroid was formed in the outer Solar System - outside the orbit of Jupiter, or from within the inner Solar System.
Their findings revealed the Ruthenium isotopes found within the Chicxulub impactor samples resembled those found in an asteroid from the Outer Solar system and did not match any from the inner Solar System.
The data disproves another long-running hypothesis, that the Chicxulub impactor was actually a comet. Though there was never any real geochemical evidence to support this theory, the Ruthenium isotopes found at the site are inconsistent with that of a comet, firmly putting this theory to bed.
These new findings in Mexico have enriched our understanding of the mass extinction event which has captured the interest of the masses for decades.