Paleontologists have captured the exact moments after an asteroid struck Earth almost 66 million years ago with newly discovered fossils that show how dinosaurs died in the catastrophe. “This is the first mass death assemblage of large organisms anyone has found associated with (the end of the Cretaceous Period),” University of Kansas paleontologist Robert DePalma said of the graveyard of fossils recently discovered in North Dakota’s Hell Creek formation. The graveyard is reportedly made up of fossils of fish, microorganisms, tree trunks, part of a Triceratops carcass, insects, dead mammals, and mosasaur bones. DePalma reportedly spent the past six years excavating the site, a snapshot of how 75 percent of life on Earth was wiped out almost instantaneously when the asteroid struck.  After crashing into waters near Mexico, the asteroid is said to have left a 90-mile-wide crater and sent parts of the earth straight up into space, sending molten rock and glass raining down on wildlife in what is known as the Cretaceous-Paleogene extinction. “You’re going back to the day that the dinosaurs died,” Pennsylvania State University paleoceanographer Timothy Bralower told The Washington Post. “That’s what this is. This is the day the dinosaurs died.”