With scorching 2370°C heat, the home of delicious maple syrup has the hottest temperature ever recorded on Earth’s surface. Aye!
Millions of years ago, ancient meteorites crashed into our planet. This heated the collision zone with hellishly hot temperatures which later on changed young Earth's atmosphere and crust, consequently affecting its habitability.
However, calculating the temperature generated during the impact is difficult. As of now, only over 2000 °C temperature can be predicted. Also, the resulting shock waves of the ancient collision caused both the meteorites and the surface rocks to vaporise. This simply means that there's a lack of physical evidence to calculate the most extreme predictions...or so we thought.
“What kinds of records can survive an event capable of vaporising rocks?” asks Benjamin Black at the University of California, Berkeley.
Nicholas Timms at Curtin University in Perth, Australia, and his team had an answer. Deep inside the Mistastin Lake crater in Labrador, Canada (28 kilometres across) is a burning past. Around 40 million years ago, the site was struck by a space rock. And there are still clues left for us to figure out how hot it became.
What is it, you say? Gemstones.
When a place is hot enough, a common mineral called zircon can transform into zirconia--a gem-like cubic. Found in the crater, the zircon acted as a thermometer as the minimum temperature need for this change is 2370 °C. That's about half of the blistering heat at the sun’s surface!
“Nobody has even considered using zirconia as a recorder of temperatures of impact melts before,” says Timms. “This is the first time that we have an indication that real rocks can get that hot.”
“These new results underscore just how extreme conditions can be in the seconds to minutes after asteroids strike a planet,” says Black. Findings enable us to have a clearer picture of what Earth was before all those space bombardment.
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