Was the Chicxulub bolide 65 million years ago an asteroid from beyond Jupiter?
According to a new study, the Chicxulub bolide that impacted the Yucatan 65 million years ago and is thought to have been a major cause of the extinction of the dinosaurs was likely a carbonaceous-type asteroid from beyond Jupiter.
The researchers attempted to pinpoint the nature of that bolide by analyzing the isotope samples from the thin layer of materials found worldwide that corresponds to the impact (dubbed the K-Pg boundary) as well number of different impact samples from different layers.
To address these questions, Mario Fischer-Gödde and colleagues evaluated ruthenium (Ru) isotopes in samples taken from the K-Pg boundary. For comparison, they also analyzed samples from five other asteroid impacts from the last 541 million years, samples from ancient Archaean-age (3.5 – 3.2 billion-years-old) impact-related spherule layers, and samples from two carbonaceous meteorites.
Ficher-Gödde et al. found that the Ru isotope signatures in samples from the K-Pg boundary were uniform and closely matched those of carbonaceous chondrites (CCs), not Earth or other meteorite types, suggesting that the Chicxulub impactor likely came from a C-type asteroid that formed in the outer Solar System. They also rule out a comet as the impactor. Ancient Archean samples also suggest impactors with a CC-like composition, indicating a similar outer Solar System origin and perhaps representing material that impacted during Earth’s final stages of accretion. In contrast, other impact sites from different periods showed Ru isotope compositions consistent with S-type (salicaceous) asteroids from the inner Solar System.
My headline poses this result as a question because these results are unconfirmed, and based on a very small sample of data. Nonetheless, this research not only gives us a better idea of the nature of the Chicxulub impactor, it does the same for a number of other important past impacts. That data in turn will help theorists refine their theories describing the early formation history of the solar system.
Sidebar: As always, there are numerous stories today in the mainstream press going ga-ga over this paper and declaring with certainty the utter truth of its conclusions. This of course is junk reporting, as there is no utter truth here, only some educated speculation based on some new data.
According to a new study, the Chicxulub bolide that impacted the Yucatan 65 million years ago and is thought to have been a major cause of the extinction of the dinosaurs was likely a carbonaceous-type asteroid from beyond Jupiter.
The researchers attempted to pinpoint the nature of that bolide by analyzing the isotope samples from the thin layer of materials found worldwide that corresponds to the impact (dubbed the K-Pg boundary) as well number of different impact samples from different layers.
To address these questions, Mario Fischer-Gödde and colleagues evaluated ruthenium (Ru) isotopes in samples taken from the K-Pg boundary. For comparison, they also analyzed samples from five other asteroid impacts from the last 541 million years, samples from ancient Archaean-age (3.5 – 3.2 billion-years-old) impact-related spherule layers, and samples from two carbonaceous meteorites.
Ficher-Gödde et al. found that the Ru isotope signatures in samples from the K-Pg boundary were uniform and closely matched those of carbonaceous chondrites (CCs), not Earth or other meteorite types, suggesting that the Chicxulub impactor likely came from a C-type asteroid that formed in the outer Solar System. They also rule out a comet as the impactor. Ancient Archean samples also suggest impactors with a CC-like composition, indicating a similar outer Solar System origin and perhaps representing material that impacted during Earth’s final stages of accretion. In contrast, other impact sites from different periods showed Ru isotope compositions consistent with S-type (salicaceous) asteroids from the inner Solar System.
My headline poses this result as a question because these results are unconfirmed, and based on a very small sample of data. Nonetheless, this research not only gives us a better idea of the nature of the Chicxulub impactor, it does the same for a number of other important past impacts. That data in turn will help theorists refine their theories describing the early formation history of the solar system.
Sidebar: As always, there are numerous stories today in the mainstream press going ga-ga over this paper and declaring with certainty the utter truth of its conclusions. This of course is junk reporting, as there is no utter truth here, only some educated speculation based on some new data.
