But there would likely have been no observers of the impact, since most life on Earth was still confined to the oceans at the time while the collision took place on land.
Britain might be a green place that's full of life today, but 1.2 billion years ago, it was a completely different place - the whole world was.
Scientists believe they have discovered the site of the biggest meteorite impact ever to hit the British Isles. Buried beneath layers of new rock and water in Minch Basin, the 25-mile-wide crater has been preserved for 1.2 billion years.
"The material excavated during a giant meteorite impact is rarely preserved on Earth, because it is rapidly eroded", Ken Amor, study lead author and researcher at the University of Oxford's Department of Earth Science, said in a statement.
Using data gathered from the field, the team of scientists determined the approximate direction from which the meteorite came and thereby located the crater.
"It was purely by chance this one landed in an ancient rift valley where fresh sediment quickly covered the debris to preserve it".
Although thousands of meteorites hit the Earth every year, they typically leave much smaller dents.
"The next step will be a detailed geophysical survey in our target area of the Minch Basin", Amor said. At that time, Scotland was around the equator, making it an arid, Mars-like landscape.
The team says that Earth and the other planets had more meteorite impacts in the distant past because the planets collided with debris left from the formation of the early solar system.
"It would have been quite a spectacle when this large meteorite struck a barren landscape, spreading dust and rock debris over a wide area", he adds.
Asteroids of the size of the one that hit the Minch are thought to strike between once every 100,000 years and once every one million years.