The infamous and deadly asteroid that slammed into Earth some 66 million years ago and wiped out an entire species of dinosaurs has its origin in our solar system, beyond Jupiter to be precise. At least a recent report published on Aug 16 claims so.
The impact of this asteroid left geochemical fingerprints, such as elevated levels of the element iridium, in a thin layer of rock found in multiple countries around the globe.
The chemical analyses of these rock sediments, which mark the boundary between the Cretaceous and Paleogene periods (also known as KPg), are helping to create a forensic profile of the killer asteroid. The asteroid, which cratered into Chicxulub in present-day Mexico, was a C-type asteroid.
This new research refutes the earlier claims that say it was a comet that hit the Earth and destroyed dinosaurs.
Geochemist Mario Fischer-Gödde of the University of Cologne in Germany along with his colleagues measured five isotopes, or forms, of ruthenium in the KPg rock layers, as well as in five impact craters that occurred between 36 million and 470 million years ago and in Earth-based platinum ores.
“Our lab in Cologne is one of the rare labs that can do these measurements,” Fischer-Godde stated adding “and it was the first time such study techniques were used on impact debris layers.”
Ruthenium is a platinum-group element, rarely found in Earth’s crust but quite abundant in asteroids and other space rocks, just like iridium. However, the relative abundance of ruthenium isotopes varies among space objects depending on where they originate.
The ruthenium signatures in the KPg rocks were recognisable from one another, which links them all to the same event, the team said. The event was definitely extraterrestrial, not from ashfall due to intense volcanic eruptions that have also been implicated in the dinosaurs’ demise.
Most meteorites found on Earth are siliceous or stony, which are asteroids originating from the nearby asteroid belt between Mars and Jupiter. This belt was also the origin of the five non-Chicxulub impactors. But the Chicxulub impactor was a carbonaceous asteroid, which originated in the outer reaches of the solar system- the place that is an ancient asteroid belt beyond Jupiter.
“Now we can, with all this knowledge… say that this asteroid initially formed beyond Jupiter,” Fischer-Godde told AFP.
(With inputs from agencies)