million years, and most likely it is as young as the last Ice Age [which ended around 12,000 years ago],” Larsen explained to Gizmodo. “We are currently trying to come up with ideas on how to date the impact. One idea is to drill through the ice and get bedrock samples that can be used for numerical dating.”
An example of the topographic data used in the new study. (Image: University of Kansas)
Also, the incident was severe enough such that evidence of the impact should be detectable elsewhere on the planet. The impact likely triggered a global cooling event by delivering copious amounts of debris, dust, and water vapour into the atmosphere, blocking incoming solar radiation. At the same time, melting ice from Greenland’s ice sheet would have reached the North Atlantic, causing a weakening or shutting down of the North Atlantic current—the current that provides western and northern Europe with its relatively mild climate. Evidence of the impact should thus exist within our planet’s stratigraphy, allowing for more precise dating of the impact. Archaeologists and anthropologists could also help in this regard, to see if and when ancient populations of humans were affected by an asteroid strike dating back to this time period.
The discovery of this previously unknown impact crater in Greenland is welcome news, both in terms of our learning about it, and the future scientific work it’s sure to inspire. Confirming the existence of this crater is just the first step—there’s now plenty of related work to be done. [Science Advances]