Extinction is a fascinating subject to me as a writer, especially if it has a dystopian plot line around a group of humans barely surviving a decimated landscape from any one of natural or manmade calamities. It’s all about the human equation, but what makes it really compelling, is a natural disaster by which we have no control. I’m obsessed with The Apocalypse Waiting Beneath Our Feet, and other earth-based, regularly-scheduled natural disasters mentioned in an article I wrote a couple years ago. Not to say meteor impacts are passé, it’s been a hotly debated subject for decades, but I viewed heavenly body impacts as random events, like chances of winning the lottery (or in this case … losing).
My attitude changed when I read a recent book review by Jim Al-Khalili of the WSJ, The Science of Shooting Stars, which discusses a unique theory fostered by Harvard cosmologist, Lisa Randall, in her new book, Dark Matter and the Dinosaurs. You can get a synopsis of Randall’s book by following the Amazon the link provided, but since you have to be a subscriber to read Khalili’s review, I’ll highlight a few part parts that caught my interest.
Randall’s book suggests “there is persuasive evidence that large bodies have smashed into the Earth on a regular basis – every 20 million to 30 million years or so.”
Randall’s theory involves one of my favorite subjects, dark matter, as an influence for bolide events, geologic term for very large impactors, hitting the planet surface.
We’ve lots of cosmic garbage floating in three orbiting junkyards; the Asteroid Belt, Kuiper Belt, and the comet spawning Oort Cloud. You can see crater-sized acne on our own moon with the naked eye. Plenty of large body impact evidence in the neighborhood. I just didn’t think big chunks of it as candidates for regularly-scheduled impacts.
Al-Khalili’s review paraphrases Randall’s book with “the solar system wobbles up and down as it orbits round the center of our galaxy”, and “passes through a disk of dark matter every 20 or 30 million years“. In simple terms, the gravitational influences of this dark matter region of our galaxy, alters the forces keeping our planetary flotsam in stable orbits with each pass.
I checked out a current roster of extinction events and the last known impact blamed for a major extinction event was 64 million years ago. Reviewing the chronology of all known large body events, three major impacts are recorded between 34-35 million years ago, with one on the American continent about 11,000 years ago that killed millions, eradicated dozens of large mammal species, and considered by some to be responsible for Noah’s flood.
Does this mean we made it through the dark matter curtain Randall is researching unscathed? Kind of hard to tell when dealing with geologic time spans measuring in millions.
It’s given me a heightened respect for Einstein’s spooky action at a distance I mentioned in Quantum Field of Dreams, and wondering if the worst is yet to come. Hopefully we have a couple more thousand years to figure out how to deal with falling cosmic junk before it happens.
Meanwhile, check out the Bolides animation of the 45,000 meteorites that have fallen since 2500 BC. Is it my imagination, or has the action kicked up a notch after 1800 AD and still going strong?
Other Reviews and commentary of “Dark Matter and the Dinosaurs” can be found here.
A primer on Meteor Terminology, from amsmeteors.org.