How to (Actually) Kill an Asteroid: A Deep Dive into NASA’s DART Mission and the Future of Planetary Defense
Sixty-six million years ago, a catastrophic asteroid impact, roughly 6 miles (10 kilometers) in diameter, brought an end to the Cretaceous period and the reign of the dinosaurs. While the probability of such a planet-killing impact happening today is relatively low, the threat from smaller, city-killer asteroids remains a very real and present danger. These smaller space rocks, numbering in the thousands, pose a significant risk of causing widespread devastation should they collide with Earth. The unsettling truth? We currently lack a fully viable defense plan.
Until recently, planetary defense against asteroid threats was largely relegated to the realm of science fiction, fuel for blockbuster movies like Armageddon and Deep Impact. However, with NASA’s Double Asteroid Redirection Test (DART) mission, reality boldly stepped onto the cinematic stage. In September 2022, NASA successfully crashed a spacecraft into Dimorphos, a small moonlet orbiting a larger asteroid, Didymos, demonstrating the effectiveness of kinetic impactor technology as a potential asteroid deflection strategy. Award-winning science journalist Robin Andrews’ captivating new book, How to Kill an Asteroid, offers an intimate and engaging account of the DART mission, painting a vivid portrait of the scientists, engineers, and the thrilling moments leading up to, and including, the historic impact.
Andrews’ personal connection to the DART mission began with a surprise. As he explains in an interview with Gizmodo, his initial fascination stemmed from a volcanologist’s perspective – a love for "dramatic, Earth-shifting stuff that makes you feel small." The prospect of an asteroid impact, quite literally “Earth-shifting,” resonated deeply. He points out the seeming disconnect between the significance of the DART mission and the relatively low-key attention it received, noting: "It just struck me as weird that that kind of subject of planetary defense hadn’t been covered that much, so I’d felt really stupid if I didn’t pitch it." This observation highlights a crucial point: the lack of sustained public and political focus on planetary defense despite its undeniable importance.
What sets Andrews’ book apart is its ability to blend rigorous science with a palpable sense of human drama. He notes the unique nature of the DART mission itself: "the point of this spacecraft was to die; if it missed and it kept living, then they had messed up." This inherent "perilous success" of the mission lends itself naturally to a compelling narrative, far removed from the typical longevity-focused goals of most space missions. The inherent risk and the one-shot nature of the mission added to the excitement and suspense.
The book isn’t just a dry recitation of scientific facts; it’s infused with humor and personality, a testament to Andrews’ skill in capturing the quirky personalities of the scientists involved. He emphasizes, "Sometimes when you speak to scientists for long enough, they sort of get more comfortable and I just got the sense that most of them are quite goofy." This approach humanizes the complex scientific endeavor, making it relatable and engaging for a broader audience. He successfully captures the atmosphere within mission control during the impact, painting a picture of palpable tension and exhilaration that culminates in a collective eruption of joy upon successful impact. "It was properly exhilarating… the buzz in that room was better than any sports game anyone has invited me to. There was so much riding on this one thing, and all the engineers looked so pale, white, nervous. You couldn’t make it up how dramatic it was—they only had one shot to do this."
Andrews draws a compelling parallel between the reality of the DART mission and the more Hollywood depictions in movies: "It was super surreal, and it felt more sci-fi to some extent rather than just straight science. …But it struck me how the science in the mission was relatively straightforward to just allow them to do something relatively simple, as in punch an asteroid." This highlights a subtle but important shift: the transition from fantastical solutions to real-world, practical approaches to planetary defense. The DART mission, while still involving impressive technological feats, focused on a relatively simple, yet highly effective concept.
A significant challenge Andrews highlights in his book is the historical underfunding of planetary defense initiatives. He describes the struggle to secure funding for the DART mission as a key hurdle: "It’s amazing that they even managed to fund this mission. It might be like the space debris problem; you just imagine that an astronaut is gonna get killed by a bit of flying debris or a piece of a rocket is gonna land on someone’s house, and maybe then someone will do something." The inherent difficulty in securing funding for a seemingly remote threat, even one with serious potential consequences, underscores the need for heightened awareness and proactive investment in planetary defense.
The book also emphasizes the crucial distinction between planet-killer asteroids and the more numerous, yet still devastating, city-killer asteroids. Andrews convincingly argues: "There’s so much written, fiction and non-fiction, about the planet killers, but these city killers—they come out of nowhere and cause damage to a random spot on Earth. As someone who wrote about volcanoes for so long, you can never stop those from erupting but you can just knock [asteroids] away." This distinction is vital in understanding the diverse range of threats and the need for a multi-faceted approach to planetary defense that addresses both large-scale and smaller-scale impacts.
Finally, Andrews expresses his hope that his book will inspire a new generation of scientists and engineers. He points out : "But [DART] is such a realistic, optimistic thing, and because the characters are so kooky and the whole idea of the mission is so pop culture, I just want it to reach younger readers. I hope it convinces them that science is cool. It’s nice to have a feel-good story for once." His desire to present planetary defense not as a bleak prediction of doom, but as a vibrant field of scientific endeavor with the potential for truly positive outcomes is both admirable and essential to galvanizing support for this critical area of research.
In conclusion, Robin Andrews’ How to Kill an Asteroid transcends the typical scientific account. It’s a gripping narrative of human ingenuity, scientific collaboration, and the determined pursuit of planetary safety. The book serves as a powerful reminder of the real and present threat posed by near-Earth objects and the urgent need for continued investment in planetary defense technologies and strategies. More importantly, it’s a story of hope, highlighting the remarkable achievements possible when science, engineering, and human determination converge on a common goal. The ultimate success of the DART mission is more than just a technological breakthrough; it’s a testament to the power of proactive measures, a beacon of hope amid the vastness of space, and a thrilling narrative deserving of a large and attentive audience.
