‘This was one of the most arduous expeditions I’ve ever done’: Scientists confirm that 15-mile-wide pit found on Google Maps is ancient meteor crater

A large pit discovered by an amateur astronomer on Google Maps in 2024 is actually a 390 million-year-old meteor impact crater, scientists have confirmed.

Joël Lapointe was planning a camping trail through Quebec’s Côte-Nord region when he stumbled upon a large indentation in the terrain, CBC reported at the time. The pit, centered around Lake Marsal, was about 25 kilometers (15.5 miles) in diameter and a near-perfect ring — it didn’t seem like a normal ditch. Lapointe eventually got in touch with French geophysicist Pierre Rochette, who said that the surrounding topography was “very suggestive” of an impact crater.

Initial testing of samples retrieved from the site contained a mineral called zircon often formed during meteor impacts. However, zircon’s presence alone was not enough to prove the crater’s extraterrestrial origin story. So a team of scientists had visited the pit in person.

“One of the key things we look for is evidence for shock metamorphism, which can only occur due to the immense pressures created by asteroid or cometary impacts — or nuclear explosions,” Gordon Osinski, a professor of planetary geology at Western University, told Live Science in an email. “Most of these features are microscopic, so you can only confirm in the lab with samples.”

But there is one feature Osinski said can be seen with the naked eye: grooves or lines in the rock’s surface called shatter cones, which are caused by shockwaves passing through the ground.

In October 2025, Osinski and a team of geologists visited the site to investigate whether any of these features were present. “This was one of the most arduous expeditions I’ve ever done — and I’ve done 25 expeditions to the Arctic and 6 continents,” he said. “The terrain was incredibly rough and rugged, plus [there were] lots of bugs.”

But they eventually found what they were looking for — shatter cones. They also discovered big cliffs of impact melt rock, created by the intense temperatures and pressures produced by a meteor impact. “You can melt literally tens of cubic kilometres of the Earth’s crust when you get a big enough asteroid hitting,” Osinski told CBC.

Taking samples from the rocks, the team dated the crater at 390 million years old.

Osinski, who runs a website called Impact Earth dedicated to verifying meteor impact sites, is used to getting emails about strange looking satellite images. “I get lots of messages from the public thinking they have found a crater and 99/100 turn out not to be the case,” he told Live Science. “This is one of those rare examples that shows this is possible.”

So far, we know of roughly 200 impact craters on Earth, 31 of which have been found in Canada. “Typically about 1 or 2 craters are discovered per year, but these are typically less than 5-10 km [3 to 6 miles] in size,” Osinski said. “[A crater of this size] is pretty rare.”

The last meteor crater confirmed in Canada was in 2010.

After the new investigation confirmed the pit was punched out by a meteor impact, Osinski, Rochette and their team named it Uhaachatik Crater following discussions with the Ekuanitshit Innu council, a council representing the indigenous people in the area. The researchers will present their work at the Annual Meeting of the Meteorological Society in Germany next month.

Speaking to Radio-Canada, Lapointe said that he was very happy to hear his discovery had been confirmed as a genuine meteor crater. “It’s not every day that an ordinary citizen finds a 390-million-year-old crater,” he said. “I encourage everyone to not ignore intuition or an observation, even if it isn’t part of your field of expertise.”

Osinski and the team will continue their work on the collected samples to learn more about the impact site. “Any crater discovered offers us insight into how craters form and the effects that they can have on Earth’s geology, biology, and climate,” he told Live Science.