Saturday Links

Dangerous asteroids, writing online, a life of Leonardo, becoming an art collector, and more.

Walter Steggles, Essex Landscape with Pollards (1932)

Good morning! The latest issue of The American Scholar contains a number of reviews and essays that are likely to interest readers of this email. Jessie Wilde, for example, writes about the scientists and engineers who track dangerous asteroids:

Asteroid scares are the stuff of science-fiction movies. Think of Bruce Willis, Ben Affleck, and the nuclear bomb in Armageddon; Téa Leoni in Deep Impact; or Meryl Streep as the president scoffing at scientists in the dark comedy Don’t Look Up. But asteroids large enough to damage our planet have actually hit Earth, and it is a statistical certainty that they will do so again. All you have to do is go to Meteor Crater in Arizona to see the evidence: at 1.2 kilometers across and 180 meters deep, the impact crater was formed 50,000 years ago by an iron asteroid. Or if you’re in the mid-Atlantic, take a look at Chesapeake Bay, thought to have been formed by an object three to five kilometers in diameter that hit Earth 35 million years ago. The crater, now buried 300 to 500 meters beneath the surface, was filled in by water. It is the seventh-largest confirmed impact crater on Earth. And, of course, the asteroid that killed the dinosaurs was the Chicxulub impactor, more than 10 kilometers in diameter, which hit 66 million years ago in what is now the northern part of Mexico’s Yucatán Peninsula.

Most asteroids are found far from Earth, between the paths of Mars and Jupiter, in a region fittingly known as the main asteroid belt. But every so often, asteroids make their way into the inner solar system. With both Earth and the asteroids traveling around the sun, orbits will occasionally intersect. The damage potential depends on the size of the asteroid, what it’s made of, its speed, and where it hits. Small asteroids approach Earth all the time but disintegrate in the atmosphere, sometimes leaving behind small pieces of space rock. These are the most frequent impacts, though some asteroids are large enough to make it all the way to the ground and form an impact crater. You may have seen a meteorite collection on a field trip. Perhaps you have held in your hands a cold stone that crashed through the Earth’s atmosphere and made it to the ground intact. Maybe if you’re a space enthusiast, you even have meteorite earrings. It’s possible that the asteroids (and comets) that hit Earth billions of years ago might have brought the raw materials needed to form life. They also brought devastation.

With a larger asteroid, the event could create a blast wave with serious thermal consequences. Alternatively, a fall into the ocean could cause tsunamis that could kill coastal residents and damage coastlines. Emergency management personnel draw the damage levels in circles surrounding an impact site like a bullseye, with “shattering windows” on the outside ring of the circle and “devastation, structures flattened or burned” at the center. But asteroids of the size that could do damage are not nearing Earth every day. As of this writing, we know of just one significant impact threat to Earth in the next century—and that asteroid, 2024 YR4, has a less than 0.002 percent chance of hitting us in 2032.

Jay Parini reviews the new Robert Frost biography: “Adam Plunkett is an eloquent and meticulous writer, and his new biographical study of Robert Frost, Love and Need, is a welcome addition to a long list of excellent books on the poet. In it, Plunkett sets out to trace connections between Frost’s life and his work—an inherently precarious undertaking. As one of Frost’s many biographers, I have skated on the same thin ice, and I appreciate the dangers. Poems arise from many sources, most of them hidden. Yet Plunkett seems to have understood the difficulties before him, and his work adds handsomely to our understanding of Frost, bringing us closer to the poems themselves.”

And Priscilla Long takes stock of Paul Hawken’s Carbon: The Book of Life: “For each fusillade of facts and statistics, I have attempted to check Hawken’s sources, all of them secondary. They are solid, if scant for such an enormous synthesis. And why he would throw in the notion that kale is bad for you because it tends to take up heavy metals is beyond me. (Full disclosure: I eat a lot of kale.) Kale does take up heavy metals, as do broccoli, cabbage, and Brussels sprouts, depending on the amount of heavy metals in the soil. I would not eat vegetables I knew to have been harvested from a toxic waste dump. And though I am nitpicking, a passage on coal asserts that “source vegetation, heat, and age determine whether coal is soft brown lignite or lustrous black anthracite.” What about bituminous coal, the main type mined in the United States? And more than a nit: the chapter on soil contains no mention of David R. Montgomery’s essential work on regenerating topsoil. Further, what happened to the important topic of worldwide plastics pollution? Yet Hawken’s book contains much excellent natural history, including the good news that when we treat Earth right, it regenerates itself, even rather quickly.”