Welcome back to the Abstract!
Since we are all super-chill and bereft of any existential dread these days, let’s take a moment to envision the grand-daddy of all apocalyptic scenarios: Death by asteroid. We have a small rock potentially incoming in December 2032 and a big rock potentially incoming in September 2182. Pick your fighter!
Then, want to make two Grand Canyons in ten minutes? I know a trick. Finally, time to calm down with some whale songs and a fish fry with libations. We’ve earned it by surviving this long in a cosmic shooting gallery. Bottoms up!
Sir Bennu the Bummer
We all know the tale of the giant dino-killing asteroid, a freak deathbringer that measured about 10 miles wide and delivered a TKO to most life on Earth. Fortunately, asteroid impacts of that scale are extremely rare, occurring once every 150 million years or so. It’s far more likely that we will get roughed up by a medium-sized asteroid, measuring a half-mile or smaller, which crash into Earth once every 150,000 years on average.
Indeed, recently scientists have been tracking 2024 YR4, a rock that is about 200 feet across and has roughly a 1 in 50 (2%) chance of hitting Earth on December 22, 2032 (Merry Christmas!). Those are very high odds for an asteroid impact, which is actually good news, because they are objectively low odds. Hazardous asteroids are extremely unlikely to hit Earth in the near term, and most never break 1% risk.
In other words, 2024 YR4 will almost certainly NOT strike Earth in seven years. But if it did, it would explode in the atmosphere and produce a powerful airburst that could kill millions of people if it occurred near a populated area (it would be the Chelyabinsk meteor on roids). As terrifying as that is to imagine, a rock the size of 2024 YR4 would still only deal regional damage and casualties could be mitigated by evacuation efforts among other preparations.
Scientists are more worried about asteroids the size of Bennu, a rock that measures a third of a mile and has a 0.037% chance of impacting Earth on September 24, 2182 (Save the date!). Obviously, that is just a teeny tiny sliver of a chance—1 in 2,700 odds—but a study this week outlines why we should take it seriously nonetheless.
“Depending on the collision parameters, an impact between a medium-sized asteroid and Earth could cause regional to large-scale devastation,” including “non-negligible threats to the habitability of our planet,” said researchers led by Lan Dai of Pusan National University.
“Beyond immediate effects such as thermal radiation, earthquakes, and tsunamis, asteroid impacts would have long-lasting climatic effects by emitting large quantities of aerosols and gases into the atmosphere,” the researchers continued.
More specifically, the team used advanced climate simulations to predict that a run-in with Bennu would inject up to 400 million tons of dust into Earth’s atmosphere. Global temperatures would subsequently plummet by about 4°C and precipitation rates would fall by about 15%. The ozone would be depleted by about 32%, exposing life on our world to high doses of harmful UV radiation.
“The initial reductions in ecosystem productivity on land and in the ocean would disrupt food availability and threaten global food security.” the researchers said. “The abrupt cooling and ecosystem collapses caused by asteroid collisions would severely reduce the habitat suitability for humans, wildlife, and terrestrial ecosystems,”
In simpler terms: we ded (skull emoji). At least, a lot of people would perish in this scenario. Of course, by the year 2182, we are all going to be pushing daisies anyway, except the Peter Thiel types that have managed to subsist on the blood of the young.
Still, I am not paying inordinate sums for daycare just to have my future descendents get whacked by some space rock. To that end, NASA has already visited Bennu with its OSIRIS-REx mission, which returned samples from the asteroid back to Earth in 2023 to get a better sense of its composition. NASA also memorably punched an asteroid in the face with the DART mission in 2022, which shifted the rock’s orbit.
These missions (among others) are building the know-how to knock dangerous asteroids off-course with spacecraft impactors, as part of a “redirect” strategy. If the odds of an impact with Bennu get higher, we may ultimately have to send a spacecraft out to give it an uppercut that will push it away from a collision course.
Deadly impacts do not make for light reading, but they are a reminder that we only exist at the mercy of weird gravitational perturbations in the asteroid belt. We are in more or less the same bind as T-rex, and Triceratops, and Mosasaurus, and all the other fantastic beasts felled by an extraterrestrial rock 66 million years ago. We may share their fate, or perhaps take a cue from the intelligent hadrosaurs who escaped that extinction (source: Star Trek: Voyager).
In any case, if you’re interested in keeping tabs on deadly space rocks (including 2024 YR4), I recommend following Robin George Andrews, who is an expert on killer asteroids and killing asteroids—a double whammy.
The Moon Has Grand Canyons to Spare
Kring, David et al. “Grand Canyons on the Moon.” Nature Communications.
Hey, want a break from thinking about space rocks crashing into things and wreaking havoc? Hahaha, not a chance. I’m a sadist and I have been given too much power!
Don’t worry, the next impact I want to bring to your attention happened a long time ago (about 3.8 billion years in the past) and affected a location where humans are only occasionally present: the Moon. A new study reconstructed the catastrophic backstory of the Schrödinger impact basin, which stretches across 200 miles of the lunar south pole.
“Schrödinger basin is the best analog surface expression for Earth’s buried Chicxulub impact crater, which is linked to the extinction of dinosaurs and most life at the end of the Cretaceous,” said researchers led by David Kring of the Lunar and Planetary Institute. “The Schrödinger impact basin is remarkable for streams of rocky debris that it ejected, carving two canyons that are comparable to Earth’s Grand Canyon in width and depth.”
Kring and his colleagues used photogeologic mapping of the canyons, Vallis Schrödinger and Vallis Planck, to reconstruct their catastrophic backstory. The team’s models suggest that they were forged by rays of rocky ejecta traveling at about 2,800 miles per hour, which violently tore gashes into the lunar landscape within ten minutes of impact. Ten minutes! Imagine blasting out two Grand Canyons in the time it takes to boil an egg. You have to hand it to space rocks: They know how to make a lasting impression.
Fun fact: Schrödinger crater is also the location of the fictional Schwarze Sonne, a Nazi Moon fortress that is literally shaped like a swastika, featured in the 2012 film Iron Sky. Now you know.
Look Who’s Talking Too (It’s Whales)
Youngblood, Mason. “Language-like efficiency in whale communication.” Science Advances.
After all that rough-and-tumble, I shall offer you the best relief planet Earth can offer: Whale songs. Is there any better salve for a mind troubled by cosmic collisions than the choruses of our oceanic cousins? It’s well-known that cetaceans, the group that includes whales and dolphins, have evolved complex acoustic repertoires that include clicks, whistles, screeches, serenades, and pulses. Often, they even have regional or familial dialects.
Now, a researcher has shown that the vocalizations of some cetaceans obey two linguistic patterns, known as Menzerath’s law and Zipf’s law, that measure linguistic efficiency. By analyzing more than 65,000 sequences from 16 cetacean species, Mason Youngblood of Stony Brook University has now confirmed that many whale songs are as efficient—if not more efficient—than human languages, revealing another layer of complexity to cetacean communication.
“One of the simplest ways to increase efficiency is by reducing vocalization time. Individuals who convey the same information in less time incur lower metabolic costs and are less likely to be detected by predators and potential prey,” Youngblood said in a new study.
“On average, whales tend to shorten elements and intervals toward the end of sequences, although this varies by species,” he noted. “Overall, the results of this study suggest that the vocalizations of many cetacean species have undergone compression for increased efficiency in time.”
Whales: They’re just like us! Well, mostly like us, except for living in the sea and being absolutely ginormous. But hey, we’ve all got lactation and linguistic efficiencies in common and that’s a good start!
Party at Patos Lagoon
Last, time to go back in time 2,000 years to party with the pre-Columbian peoples of Patos Lagoon in southern Brazil. This coastal wetland region is one of many places where ancient communities built earthen mounds called Cerritos that are packed with pottery shards, human and animal remains, and agricultural byproducts like seeds and beans.
A team has now analyzed residues preserved in 54 pottery shards recently retrieved from two cerritos dating back 1,200 and 2,300 years, which are affiliated with the Charrua and Minuano cultures. The results suggest that these pots held cooked fish and may have even been vessels for alcoholic beverages made from fermented crops, such as maize. The researchers speculate that these ancient peoples may have timed boozy festivals to coincide with seasonal runs of migrating fish, such as the Whitemouth croaker.
“Intriguingly…food residues from Cerritos ceramics show that vessels were used for either cooking estuarine fish, or plant products,” said researchers led by Marjolein Admiraal at the University of Alaska Fairbanks (the research was conducted during her previous position at the University of York).
“Microbial-derived lipids were predominantly associated with the latter, suggesting that plants were fermented, presumably to make alcoholic beverages,” the team said. “We suggest that these sites, at least in part, functioned as prominent monuments in a frequently flooded landscape conducive to seasonal mass capture of fish, and that social aggregation and ritual feasting were major activities.”
There’s nothing like social aggregation and ritual feasting around earthen mounds to start off the weekend. Let the good vibes drown out the bad.
Thanks for reading! See you next week.