Humanity dodged a bullet a week ago. By “bullet” I mean “100-metre wide rock travelling at a hundred times the speed of sound”. And by “dodged” I mean “sailed on blissfully ignorant of our possible doom”.
Asteroid 2019 OK streaked past Earth at lunchtime (NZ time) on 25th July, getting within 80,000 km, which in space terms is thinner than an after-dinner mint.
The asteroid was only noticed a day before its closest approach - no time for any planet-saving heroics, even if we knew what to do.
The only comparable event in recent history is the Tunguska event in 1908, when an asteroid or comet about the same size came down over Siberia, causing an explosion that flattened 80 million trees over 2,000 square km. Fortunately, Siberia is only slightly more populated that interplanetary space.
Asteroids, Climate Change, Farming, and Measles
Asteroids, appearing unbidden from the black emptiness of space, make for a great plot device when you need some unlikely magic to push your story along.
12,000 years ago the climate cooled rapidly. Nobody knows what caused the change, but one candidate is an asteroid strike. An asteroid strike at the dawn of human history is too good for a pseudo-archaeologist to pass up and this asteroid strike also gets the blame for destroying Atlantis.
Try searching for anything serious on this prehistoric cold snap, known as the Younger Dryas, and you’ll soon be neck deep in lost civilisations.
The Younger Dryas may have triggered the shift from foraging to farming, which in turn gave us measles, a disease originally transmitted from domesticated sheep. Now the same online recommendation engines that are twisting our early history are also helping to bring back our ancient diseases. (See my post Measles Goes Viral.)
T. rex and the Crater of Doom
The asteroid impact that we all know best is the one that killed the dinosaurs. For a readable and lively retelling of the scientific detective story that led to the discovery of the impact crater in Mexico, see T. rex and the Crater of Doom.
From the book of rocks comes the history of the Earth
The book is written by Walter Alvarez, the son in the father-son team that made the discovery. It vividly describes what happened that day 65 million years ago, the battle between the gradualists, who believed nothing in geology happens quickly, and the catastrophists, and the final discovery of the vast submerged Chicxulub crater.
This short, personal story is an easy, fun introduction to one of the milestone events in Earth’s history.
Asteroids are not all death and destruction. They’re also a trillion-dollar opportunity. Metallic asteroids contain vast quantities of valuable raw materials. Commercial ventures are already under way, looking to stake their claim, and NASA recently announced construction of its first mission to a metallic asteroid, Psyche, which will launch in 2022.
For what happens when a quadrillion dollars worth of gold shows up, see my recent post: Who Wants to Be a Trillionaire.
Try and avoid any extinction events before next week. Until then, thanks for reading,