Finally, a definitive, concrete answer is out: Dinosaur extinction, along with a host of other species 65.5 million years ago, was caused by a massive asteroid that crashed into the Gulf of Mexico, creating a worldwide impact, an international panel of researchers stated on Thursday.

The experts have unanimously endorsed evidence that a space impact was behind the mass extinction event that killed off the dinosaurs, the consensus of which was reached after conducting the most wide-ranging analysis yet of the evidence.

In the detailed study, published in Science journal, alternative theories such as large-scale volcanism have been entirely ruled out by the research panel.

A panel of 41 experts closely scrutinized and reviewed 20 years' worth of research, to determine the cause of the Cretaceous-Tertiary (popularly known as the K-T) mass extinction, around 65 million years ago.

According to the report, the “7.5-mile-wide asteroid” was traveling at a speed about “10 times that of a rifle bullet when it hit, releasing a billion times more energy than the Hiroshima atom bomb”.

What followed was a global catastrophe. The impact blew dirt and rock around the world, set massive wildfires, knocked down forests worldwide, triggered massive tsunamis and earthquakes of magnitude 11 or larger and caused parts of the continent to slip into the ocean.

More than half of all species were wiped out from the face of the planet due to the extinction, including the dinosaurs, bird-like pterosaurs and large marine reptiles, clearing the way for mammals to become the dominant species on Earth.