A kilometer-wide asteroid that crashed into Earth 58 million years ago is thought to have caused an enormous impact crater.
The impact that killed off most dinosaurs was eight million years ago.
The crater was thought to have been made by a meteorite between 12,000 and 3 million years ago.
The last ice age ended around these dates, and the asteroid that created it seemed to have crashed into an already formed ice sheet.
It is mostly based on circumstantial evidence, like radar scanning. Researchers have been trying to figure out the true age of the 31 kilometer-wide indent since it was first discovered.
Direct evidence has proved difficult because much of the evidence lies beneath a kilometer of ice.
Researchers from Sweden andDenmark have both landed on the same date using two different dating methods.
"Determining the new age of the crater surprised us all," says Michael Storey from the Natural History Museum.
The crater's actual age is much older than people thought.
There is an outline of the impact crater. The Natural History Museum ofDenmark is a museum.
Rocks and sand from the bedrock beneath the ice sheet can be seen on the riverbanks downstream of the glacier. The impact event can be dated by using melt rock samples.
Researchers at the Museum of Natural History in Sweden focused on the riverbank's rocks, which contain the mineral zircon. When this mineral is hit by a meteorite, it forms new crystals, which are radioactive and reject lead.
The age at which this crystallization began can be revealed by the ratio of uranium to lead.
Researchers used a technique called argon-argon dating. The team was able to release gas from individual grains by heating sand downstream of the glacier.
The amount of radioactive decay that had occurred since the meteorite hit was determined by the amount of gas used to calculate it.
According to the argon-argon method, the Hiawatha asteroid hit Earth sometime between 56 and 66 million years ago, while the uranium-lead technique landed on a date 58 million years ago.
If the Hiawatha had crashed into ice, it would have looked like this. Carl Christian Tofte is a person.
The event that caused the extinction of the dinosaurs was eight million years ago, but the Hiawatha crater is six times smaller.
The impact of the Hiawatha would have been a million times more powerful than an atomic bomb, which would have had a huge impact on the local and global climate.
The late Pleistocene would not have looked like this today. An abundance of animal life is likely to have existed on the island.
The Hiawatha meteorite may have altered the climate millions of years ago.
Science Advances published the study.
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