A second asteroid may have struck Earth when the dinosaurs died out

The person is Michael Le Page.

A 9 kilometer-wide crater has been found buried beneath the sea floor. It was made around the time of the large impact that wiped out most dinosaurs, leading to speculation that it was caused by a piece of the asteroid that broke.

It fits the bill for an impact crater according to Uisdean Nicholson.

The feature in the data was noticed by Nicholson. The crater is on the continental shelf a few hundred kilometres off the coast of Guinea and is buried beneath around 300 metres of silt.

Nicholson says the structure has all the characteristics of an impact crater, including a raised rim and signs of ejected material outside the crater itself. Veronica Bray is a team member at the University of Arizona in Tucson.

The same time as the 180 kilometer-wide Chicxulub crater in Mexico, the Nadir crater formed. It is thought that it was made by a piece of the asteroid that broke off.

The two craters are very close to each other. Nicholson thinks that the asteroid could have been broken apart by gravity when it passed close to Earth.

The comet was ripped into pieces by Jupiter in 1992 and then hit the planet in 1994. Over the course of six days, at least 21 fragments hit Jupiter.

There is a chance that the asteroid broke up into several pieces. Other impact craters may have been destroyed by the earth's movement. Most of our oceans are formed when asteroids hit the water.

The discovery of the Chicxulub impact is exciting according to the researcher. There are a lot of features that are consistent with an impact origin.

Collins doesn't think that the event is linked to the impact of the Chicxulub. He thinks that the two events are not related.

Nicholson thinks it's possible. A proposal has been put in by his team to drill through the Nadir crater to confirm if it is an impact structure.

A major extinction wouldn't have been caused by the impact alone. The study states that the event would have affected the surrounding region by creating waves that were 500 metres high. He says it would have been a big event.

The asteroid could have caused some global warming by releasing carbon from the black rocks it struck and also by destabilizing methane on the sea floor.

Within a few hours, the entire planet was covered in dust from the Chixculub impact. All dinosaurs were wiped out and the long period ended with a bang. The fossils of animals killed by the impact have been found in North Dakota.

Science Advances was published in the journal.