
A 70-kilometer-wide (43-mile) impact structure in the Australian Outback has been dated to 2.2 billion years old, making it the oldest known asteroid crater on Earth. Fascinatingly, this asteroid likely plunged into a massive ice sheet, triggering a global-scale warming period.
New research published today in Nature Communications confirms the Yarrabubba crater in western Australia as the oldest accepted impact crater on Earth. At an estimated 2.229 billion years old, it’s nearly 210 million years older than the 200-kilometer-wide (120-mile) Vredefort Dome in South Africa and 380 million years older than the 180-kilometer-wide (112-mile) Sudbury impact structure in Ontario, Canada.
The first author of the new study, Timmons Erickson from NASA Johnson Space Center and Curtin University in Australia, along with his colleagues, also presented evidence suggesting the 7-kilometer-wide asteroid that formed the Yarrabubba crater hit a massive ice sheet, sending tremendous amounts of water vapor into the atmosphere and potentially warming the climate around the globe.
https://www.nature.com/articles/s41467-019-13985-7
https://gizmodo.com/world-s-oldest-known-impact-crater-confirmed-in-austral-1841130758