Friday, December 29, 2017

NOVA: “Day the Dinosaurs Died” (WGBH/PBS-TV, aired December 27, 2017)

by Mark Gabrish Conlan • Copyright © 2017 by Mark Gabrish Conlan • All rights reserved


Artist’s reconstruction of the Chicxulub crater from Science magazine

Two nights ago I watched a fascinating special on the NOVA series, “Day the Dinosaurs Died” (notice the title does not begin with the definite article, though it occurs as the second word), an engaging documentary of an expedition to an undersea crater in the Gulf of Mexico called Chicxulub (after the Mexican village on the shore near the crater) that scientists believe was formed about 66 million years ago when an asteroid seven miles in diameter slammed into the Earth and created such cataclysms the world’s temperature permanently changed, millions of species died off, and the dinosaurs’ reign as the most advanced life forms on earth ended in a matter of weeks, The expedition went out in March 2016 (there’s an advance article about it from Science magazine online at http://www.sciencemag.org/news/2016/03/scientists-gear-drill-ground-zero-impact-killed-dinosaurs, and a followup from November 2016 during the expedition by the same author, Eric Hand: http://www.sciencemag.org/news/2016/11/updated-drilling-dinosaur-killing-impact-crater-explains-buried-circular-hills) and essentially used offshore oil drilling equipment to dig up rock cores from the crater’s so-called “peak ring.” This is an inner ring of a crater formed only after the most significant impacts from the largest objects. Only two other craters on Earth have been known to have had peak rings, the 2 billion-year-old Vredefort crater in South Africa, and the 1.8 billion-year-old Sudbury crater in Canada — and those are both so old the peak rings have long since eroded away. The nearest crater to Earth with a peak ring aside from Chicxulub is on the moon. 

In order to explore it they took an offshore oil drilling rig (appropriate because Chicxulub had been discovered in the first place by an offshore oil drilling crew from Pemex, Mexico’s state-owned oil company) and instead of drilling for oil, drilled for rock samples that would tell the history of the crater. They found quite a few anomalies, including a great rift at the impact of the crater that both brought up granite to the surface (granite is a rock usually formed inside the earth and it generally comes up from volcanic eruptions) that had been embrittled and literally crumbled in the researchers’ hands. There were also anomalies in the rock itself that supported the theory that a) the dinosaurs died off relatively quickly and b) the Chicxulub asteroid crash was the cataclysmic event that triggered it. The show briefly explored what kinds of life could have survived in the post-crash environment and suggested — as other theorists have come to believe — that the modern-day descendants of dinosaurs are not reptiles but birds. Though it’s annoying that one of the funders of NOVA is the “David H. Kock Fund for the Advancement of Science” when David Koch and his brother Charles, both mega-billionaires from their investments in fossil fuels, are simultaneously running political super-PACs that deny science, particularly when it comes to climate change, and helping elect the goons in the Republican Party that are empowering the fossil-fuel industry to destroy the planet even faster than they were doing before, this is still an interesting program and it had the added fringe benefits that one of the scientists in charge of the project, Sean Gulick of the University of Texas at Austin, was a quite sexy long-haired blond man whom it was fun to look at even though this show didn’t show the bare-chested glimpes of some of the male participants in previous NOVA-funded scientific experiments. And certainly the show’s basic message that life is fragile and even the seemingly best-adapted species can fall victim to a climate event and die out in a remarkably short period of time is one that should piss off the Koch brothers but we reality-based people should take to heart!