The Río Cuarto Craters
A pilot spotted a line of long, shallow hollows in the Argentine pampas that looked as if something had skimmed the ground.
What was reported
In 1989 a pilot flying over farmland near Río Cuarto, in Córdoba province, noticed a group of long, oval hollows in the ground, the largest about 4.5 km long, all pointing the same way. In 1992 a study in the journal Nature proposed they were made by an asteroid striking at a very low angle, within the last 10,000 years.
Pieces of glassy rock found nearby seemed to support the idea.
Explanations offered
Later studies argued that the hollows are natural, wind-carved features like others found across the pampas, and that the glass came from different, older events. The question is still argued over.
- When
- Spotted in 1989
- Where
- Río Cuarto, Córdoba, Argentina
- Witnesses
- A pilot flying over the pampas
- Status
- Disputed
Famous cases are real, widely reported events. Each file sets out what witnesses said and the explanations that have been offered, without taking a side.