12,900 Years Ago: North American Comet Impact Theory Disproved
Tuesday, January 27, 2009 - 02:35
in Earth & Climate
New data disproves the recent theory that a large comet exploded over North America 12,900 years ago, causing a shock wave that traveled across North America at hundreds of kilometers per hour and triggering continent-wide wildfires. Scientists tested the theory by examining charcoal and pollen records to assess how fire regimes in North America changed between 15 and 10,000 years ago, a time of large and rapid climate changes.