A number of exciting scientific achievements were reported last month, including the first photograph of a black hole, the unearthing of a fossil belonging to a previously unknown cousin to Homo sapiens who lived 50,000 or so years ago, and the discovery of a new fossil site in North Dakota that marked the extinction of dinosaurs 66 million years ago.

The latter event received the most press, and rightly so. Just image what it would be like to watch a small, glowing moonlike object traveling 45,000 mph approaching the earth and growing larger and larger. When it strikes, it will blast a hole in the atmosphere and generate a supersonic shock wave. The aftermath would be firestorms that incinerate the landscape for miles. Even creatures thousands of miles away would be doomed, if not by fire and brimstone, then by mega-earthquakes and waves of unimaginable size. This may have happened when a gigantic asteroid struck a shallow sea off the coast of Mexico where the Yucatan peninsula is today. At that very moment the Cretaceous period ended and the Paleogene period began.

The event was described in a fascinating article in the New Yorker on April 8. According to the author, computer models predicted that, "within two minutes of slamming into the Earth, the asteroid which was at least six miles wide, had gorged a crater about eighteen miles deep and lofted twenty five trillion metric tons of debris into the atmosphere. The energy released was more than that of a billion Hiroshima bombs, but the blast looked nothing like a nuclear explosion, instead the initial blowout formed a ‘rooster tail,’ a gigantic jet of molten material, which exited the atmosphere, some of it fanning over North America. Much of the material was several times hotter than the surface of the sun and it set fire to everything within a thousand miles. In addition, something truly strange occurred. An inverted cone of liquefied, superheated rock rose, spread outward as countless red-hot blobs of glass, called tektites, blanketed the Western Hemisphere. Within hours or perhaps minutes of the titanic collision, sea creatures were swept inland by tsunamis and earthquakes, tossed together and deposited with a diverse array of landlocked life including trees, flowers and vanished types of freshwater fish. The tektites raining into water, clogged the gills of fish, which were then killed by surges of water."

These contents formed the North Dakota deposit that paleontologist Robert DePalma uncovered and were described in the New Yorker article. As evidence, the gills of the fish were isotopically dated to 65.8 million years ago. As the earth rotated, the airborne material converged on the opposite side of the planet where it fell and set fire to the entire Indian subcontinent. About 75% of all species went extinct, more than 99.9999% of all living organisms on earth died.

Much of what DePalma found confirmed work done in 1980, when Luis Alvarez and his son Walter, a geologist, made public their theory that the dinosaurs (except birds) were killed by a massive asteroid strike. In the early 1980s, the discovery of a clay layer rich in iridium, an element found in asteroids, at the end of rock record of the Cretaceous at sites around the world led researchers to link an asteroid to the End Cretaceous mass extinction. A wealth of other evidence has persuaded most researchers that the impact played some role in extinctions. But no one other that DePalma has found direct evidence of its lethal effects. DePalma and his colleagues say the killing is captured in forensic detail in the North Dakota deposit, which they say formed in just a few hours, beginning perhaps 13 minutes after impact.

DePalma and others have been working on their find since 2012, and he also recruited Walter Alvarez to the team. Alvarez provided the meticulous archeological approach required for such a massive undertaking. It should be mentioned, however, that other scientists question DePalma's interpretations.

According to Blair Schoene, a geologist at Princeton University, the site does not definitively prove the impact event alone triggered the extinction. He and some others think the environmental turmoil caused by the volcanic activity in what is now central India may have taken a toll even before the impact. And until a few years ago, some researchers had suspected the last dinosaurs vanished thousands of years before the catastrophe.

Several more papers about DePalma's discovery are now in preparation and they will likely more fully describe the significance of the fossil findings. It may be the best evidence yet that at least some dinosaurs may have been alive to witness the asteroid impact or that dinosaurs truly died on that very day.

Max Sherman is a medical writer and pharmacist retired from the medical device industry.