Popigai crater

The Popigai crater (or astrobleme) in Siberia, Russia is tied with the Manicouagan Crater as the fourth largest verified impact crater on Earth. A large bolide impact created the 100-kilometre (62 mi) diameter crater approximately 35 million years ago during the late Eocene epoch (Priabonian stage). It is conjectured that it may have influenced the Eocene–Oligocene extinction event.

The crater is 300 km (190 mi) east from the outpost of Khatanga and 880 km (550 mi) NE of the city of Norilsk. It is designated by UNESCO as a Geopark, a site of special geological heritage. There is a small possibility that Popigai impact crater formed simultaneous with the approximately 35-million-year-old Chesapeake Bay and Toms Canyon impact craters.

For decades the Popigai crater has fascinated paleontologists and geologists, but the entire area was completely off limits because of the diamonds found there and the mines constructed by gulag prisoners under Stalin. However, a major investigatory expedition was undertaken in 1997, which greatly advanced understanding of the enigmatic structure. The impactor in this event has been identified as either an 8 km (5.0 mi) diameter chondrite asteroid, or a 5 km (3.1 mi) diameter stony asteroid.

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