Scientists have thrown light on the day when a giant asteroid smashed into our planet - unleashing a terrible firestorm which blotted out the sun, and killed the dinoaurs.
Scientists dug retrieved cores 4,265 feet (1,300m) below the submerged 'Chicxulub' crater, where an asteroid hit Earth 66 million years ago.
It revealed proof of an explosion with the force of 10 billion atomic bombs of the size used in World War II.
The charcoal, granite and other sediments revealed details of how the impact unleashed huge tsunamis and wildfires across the planet - along with a cloud of sulphur which blotted out the sun.
Professor Sean Gulick, a geoscientist at The University of Texas at Austin, said: 'They are all part of a rock record that offers the most detailed look yet into the aftermath of the catastrophe that ended the Age of Dinosaurs.'
Three quarters of animal species were wiped out - including the dinosaurs.
Some were burned alive or drowned - but most shivered and starved to death.
The impact blasted so much sulphur into the atmosphere it blocked out the sun, say the British and US led team.
Prof Gulick described it as a short-lived regional inferno - followed by a long period of global cooling.
He said: 'They fried or froze.
'Not all the dinosaurs died that day - but many dinosaurs did.'
The researchers analysed a 425 feet long core extracted from the 'peak ring', a circle of hills 60 feet underwater at the centre of the crater.
The material was deposited within a day of the impact - a rate that's among the highest ever encountered in the geologic record.
The crater was filled with debris in hours - either produced at the impact site itself or swept in
by seawater pouring in from the surrounding Gulf of Mexico.
This breakneck rate of accumulation means the rocks record exactly what was happening within and around the crater at the time.
Lead author Prof Gulick said: 'It's an expanded record of events that we were able to recover from within ground zero.
'It tells us about impact processes from an eyewitness location.'