In the new movie Don’t Look Up, available on Netflix on Friday, astronomers played by Jennifer Lawrence and Leonardo DiCaprio try to tell the world that a comet 9 kilometers wide will collide with the Earth in six months, utterly destroying most life and ending human civilization. This is decidedly not Armageddon but a dark comedy. When the astronomers appear on a talk show to get the message out, one host asks if the comet can land on his ex-wife’s house, and the other chides the astronomers for not being light enough for their morning segment. Media training is recommended.
It’s a cliché that every disaster movie begins with someone ignoring a scientist, because our real-life disasters start the same way. Don’t Look Up is a thinly veiled critique of society’s feeble response to scientists’ warnings about the existential threat of climate change, and has special relevancy now because of the inability of many of us to understand and act on what scientists tell us about how viruses work. As an astrophysicist, I have felt sympathy for scientists trying to convey these dangers: Climate change is happening on scales too large to perceive easily; viruses are too small to be seen directly. I have also smugly assumed that if a mountain-size comet, plainly visible in the sky, were barreling to Earth at 25,000 mph, my colleagues and I could communicate the dangers.
Don’t Look Up has made me seriously question that. No one in the film grasps what must be done, the astronomers included. Like anyone watching this movie, I rooted for the astronomers trying to save the world and booed the talking heads and other idiots who couldn’t see the danger. But as a scientist, too, I also found myself shaking my head and asking: Are we just as unteachable?
Scientists are expertly trained to imagine and quantify what might have happened in the past and how the future might unfold, and to plan accordingly. As depicted in the movie, there really is a Planetary Defense Coordination Office at NASA that plans and sponsors telescope surveys in Hawaii, Arizona, and around the world. Its congressional mandate is to find at least 90 percent of the estimated 25,000 near-Earth asteroids at least 140 meters in size (each capable of destroying a city with the energy of an H-bomb). Based on the rate of discovery, about half have probably been found; none found so far are on a collision course in the next century. Our ability to deflect any hazardous asteroid we discover is limited, but NASA is preparing for the eventuality. In November, it launched the Double Asteroid Redirection Test mission. In September 2022, as one spacecraft watches, another will collide with a small asteroid to see how much momentum can be transferred to it (just the momentum of the spacecraft, or extra momentum from ejected surface rock?). We are probably safe for centuries to come. But when astrophysicists extrapolate from familiar examples like the 2013 Chelyabinsk meteor or Meteor Crater in Arizona, the math tells us that “planet-killer” impacts are inevitable over hundreds of millions of years.
Indeed, they have happened, and the impact of a 10-km-wide asteroid near present-day Chicxulub, in Mexico’s Yucatán Peninsula, precipitated one of the largest mass extinctions on Earth, including the demise of all (non-avian) dinosaurs. The death of the dinosaurs had been an unexplained mystery until geologist Walter Alvarez and physicist Luis Alvarez in 1980 discovered traces of asteroidal iridium in a worldwide clay layer deposited about 66 million years ago.* They predicted an impact crater 100 miles wide and 20 miles deep. Incredibly, just such a crater was later found, buried under 2,000 feet of sediment in the Gulf of Mexico.
Planetary scientists studying craters on other planets and moons, with paleontologists, have pieced together and widely publicized the events surrounding this impact, and how it led to massive loss of life on Earth. Today, everyone “knows” an asteroid killed the dinosaurs. And yet it’s easy to believe Don’t Look Up’s premise that the public has not internalized how destructive this would be. As someone working in this field, I found myself wondering, as I watched the movie, what I would say if I were in the place of Lawrence’s and DiCaprio’s characters.
I would want to remind people that there was no warning. Until the instant the asteroid entered the Earth’s atmosphere, coming in at a steep angle from the northeast at 25,000 mph, it was probably a perfectly normal night in the Cretaceous. Everything changed in a blink of an eye. No triceratops had time to gaze at a space rock hurtling through the air, trailed by smoke, and contemplate its imminent demise; rather, literally one second later, the asteroid the size of Mt. Everest had buried itself most of a mile beneath the seafloor. The Earth’s crust stopped the planetary bullet, but tremendous energy was released in an instant, as much as 100 million H-bombs exploding simultaneously. More than 1 million billion tons of rock were launched into ballistic orbits. Seismic waves raced through the Earth’s crust outward in all directions. Much of the Earth would have experienced ongoing magnitude 9 earthquakes, stronger than any felt by any living person. Then came the fall of all the ejected rock back through the Earth’s atmosphere. One shooting star glowing from the heat of its reentry is pretty; the unrelenting glow from trillions of shooting stars turned the sky into an oven, and fern forests around the world into ash. Finally came the winds generated by the explosion, scouring every continent at hundreds of miles per hour, and then tsunamis taller than skyscrapers that would have crashed onto every shoreline across the world. In the years it took for the ash from the impact and the forest fires to settle out, no sunlight reached the ground. Would that convince the public of how unsurvivable a comet impact would be? Or would the media consultants explain to me that those numbers are just too unimaginable and meaningless?
Maybe I could evoke a response by telling the story of what happened to the creatures in one place, like the Tanis site in North Dakota, the location of a remarkable discovery announced by paleontologists in 2019. Sixty-six million years ago, a river flowed there into the shallow sea intersecting North America, 2,000 miles from Chicxulub. The seismic waves from Chicxulub generated 30-foot-high surges of water called seiches, that piled up local freshwater fish and saltwater fish from miles away into heaps on the shore. There are hints of a triceratops carcass in the mess of tangled bones. As the fish lay there gasping for breath, the rock reentering Earth’s atmosphere fell as white-hot molten glassy beads. As the fossils at Tanis reveal, these glass beads got stuck in tree sap, filled ants’ nests, and collected in the gills of the dying fish. At this one site, the death tableau was buried and preserved in sediment soon after, before the hurricanes and forest fires, but this destruction was repeated everywhere around the world. Nearly everything was killed, including almost all four-legged animals over 50 pounds. Only 25 percent of all plant and animal species managed to leave any descendants at all. Would hearing that spur people to act? Or would the media consultants admonish me for being too doom-and-gloom?
If I’m honest with myself, I doubt I would fare better than the astronomers in Don’t Look Up. Denialism is just too strong. Mammals are just lucky creatures whose ancestors happened to survive the Chicxulub impact, but it’s human nature to blame the dinosaurs for their own demise and believe our own rise was destined or deserved. If they really wanted to live, maybe the dinosaurs should have developed social media and a space program. (How would a tyrannosaur hold their smartphone anyway, with those tiny arms?) We forget what an evolutionarily perfect killing machine T. rex was. It was the largest predator in the Americas, and when it evolved, all medium-size predators went extinct. It was the master of its environment, and mammals were not—until that environment disappeared.
Astronomers, planetary scientists, and paleontologists have studied the Chicxulub impact and know what a comet impact today would entail. This is not the bailiwick of nonscientists. In Don’t Look Up, the politicians calculate exactly how the comet will affect their midterm chances, the billionaires build business plans to profit off the comet, and the media analysts test how well the comet is polling. Their denialism is the dark joke that bleakly rings true. But the scientists’ denial is equally tragic. Their own lives depend on them getting politicians and the public to recognize what to do, yet they have no clue how to craft and market-test a message. They are constantly admonished to get some basic media training, but they seem to blow it off, oblivious to its importance, They figure the message is enough; it never seems to register with them that they need to learn how to reach people. They do try their best to engage the public, but they aren’t very smart about it.
Scientific training prepares us to have excellent clarity of thought about the physical world; we are masters of understanding the physical environment. But the power to alter the physical world depends on collective effort, and therefore on changing hearts and minds in the human sphere. Politicians, industrialists, the media are masters of that human environment—until that environment disappears.
I’m not prepared to say that the uneasy alliance of these factions we call human civilization will go the way of the dinosaurs. But as Don’t Look Up reminds us, our inability to act effectively on threats from climate change to pandemics means we are a civilization of dinosaurs, each of us perfectly evolved to work with impressive efficiency within an environment that could disappear overnight.
Correction, Dec. 23, 2021: This piece originally misidentified Walter Alvarez as a physicist and Luis Alvarez as a geologist. Walter is the geologist, and Luis was the physicist.