If a 440-kiloton atomic bomb exploded on the earth today, people would notice. After all, the A-bomb that exploded about 1900 feet over Hiroshima, Japan, on August 6, 1945, was only around 16 kilotons; even so, it killed at least 90,000 people–and perhaps as many as 166,000.
So it’s interesting that on February 15, 2013, the skies above Chelyabinsk, Russia, erupted with the equivalent of a 440-kiloton nuclear bomb. This explosion, though, occurred some 30 miles above the earth’s surface; it was caused by an asteroid-strike from space. Thankfully, nobody was killed, although there were a great many injuries and much property damage on the ground below.
Yet since the Chelyabinsk strike carried no human “fingerprints,” it didn’t attract much attention. In the way we humans think, “Acts of God,” such as an asteroid-strike, are not really worth worrying about–no matter how devastating they might be. Instead, countries prepare for “Acts of Men” and then go to war.
But what if, in the future, human action could mimic an Act of God? What if humans could direct an asteroid strike against earth?
Today, in 2014, this is no longer a completely idle question. It’s now possible to imagine the weaponization of space in a new way: Call it Directed Deep Impact (DDI).
And as so often has been the case, this potential weaponization, this DDI, could come about through what could be considered an ironic process–that is, inverting a peaceful intent into a warlike outcome.
As for the peaceful intent, that was provided by the European Space Agency’s Philae lander. On November 12, the Philae, carried aboard the Rosetta spacecraft, completed a 10-year, four-billion-mile voyage and touched down on the comet 67P/Churyumov-Gerasimenko. According to reports, the Philae mission has not been a complete success; the lander touched down in a shadow, and is thus deprived of the solar power it needs to operate. Since November 14, the Philae lander has been asleep, although, according to its Twitter feed, it has been merely napping. Perhaps, if the sun’s rays once again reach it, Philae will come back to life; in any case, the Europeans have proved a valuable concept. They can put down a spacecraft on a comet going 80,000 mph. Is it the sum total of their ambitions to simply know more about comets?
Indeed, insofar as humans have shown that they can land on a comet, they have done something more consequential than man’s landing on the moon back in 1969. Yes, the Apollo mission was “one giant leap for mankind,” but the Philae landing is potentially even bigger–for better for worse, we could soon have the capacity to affect the course of a comet.
Yes, it’s possible that a Philae-like lander could help the earth, by knocking a comet off a deadly collision course. That was the plot of the 1998 movie ArmageddonDeep Impact. Coincidentally, that same year, Hollywood produced another movie about a bolide that struck the earth and killed hundreds of millions: .
Yet there’s another possibility: Now that humans have “touched” a comet, we must ask: What if such touching could also alter the course of a comet in a harmful manner–to guarantee a Deep Impact? That is, what if humans could alter a comet’s course in such a way as to guarantee that it struck the earth? Even a particular target on the earth? A 2011 article on space.com downplayed the idea, but one opinion piece is hardly the final word in the annals of human genius–or malevolence.
Indeed, the Europeans in particular don’t seem very warlike anymore. But dozens of countries have some sort of space program; moreover, history tells us that all technologies have a “dual use”–a use that can help, and a use that can kill. And over time, humanity explores every possible use of a new technology.
Indeed, just on November 29, Japan launched its own rendezvous-with-an-asteroid mission; a Japanese H-IIA rocket lifted off from the Tanegashima Space Center. It will travel for six years to reach the 1999 JU3 asteroid. And what will the Japanese probe do when it gets there? “It will blast a crater in the asteroid to collect virgin materials unexposed to millennia of solar wind and radiation, in the hope of answering some fundamental questions about life and the universe.” In other words, it’s all for research–but once a few more countries get in the business of blasting asteroids, something else could happen, including by accident.
But wait a second, one might say: Is it really possible that one group of humans could attempt to divert a comet to strike the earth? How could they achieve such precise targeting to hit an enemy? Or would it just be a suicide strike against the earth–say, if we don’t meet our greenhouse gas targets? As noted, over time, humanity explores every possible use.
The Chelyabinsk asteroid–the term for an object that hits the earth is a bolide–was about 56 feet wide. But, traveling at a speed of at least 40,000 mph, it exploded with enormous force when it hit the earth’s atmosphere. Once again: An object about the size of trailer truck exploded with the force of 440 kilotons of plutonium. If it had been bigger, it could have done infinitely more damage. The P-67 comet upon which Philae landed, by comparison, is a full two miles wide.
It’s estimated that the bolide that wiped out the dinosaurs 66 million years ago was between six and nine miles wide; that’s all it took to wipe out most of the living things on earth. Moreover, scientists now believe that this the “Cretaceous-Paleogene extinction event” was not the first; there had been several others earlier. In other words, every so often in planetary history, some giant object hits the earth and destroys most every living thing. So today, the risk of a bolide is both small, and yet profound. It’s highly unlikely to happen in any one year, or even one lifetime, but it’s highly likely to happen eventually, and highly likely to be profoundly destructive when it does.
So luck is a variable, and so is location; the human race was fortunate that the 2013 bolide hit a a mostly unpopulated area. Russia, being as huge as it is, understandably receives many hits; perhaps the most famous “deep impact” came in 1908–again, in a depopulated part of Siberia.
Meanwhile, today, almost three-quarters of the earth’s surface is water, and just three percent of the land surface is urbanized. So we can simply hope that we continue to stay lucky, and that bolides hit only in empty quarters. Still, the recent experience of tidal waves–the 2004 Indian Ocean tsunami killed at least 280,000 people–reminds us that a population near the ocean can be at great danger from anything that makes a sudden impact on the water level.
And yes, from the sky, there’s great danger: NASA is currently tracking some 10,000 Near Earth Objects, although the true number of NEO’s is in the millions. And of course, the universe, consisting, as it does, of at least 100 billion galaxies, has a near infinite capacity to put space stuff on a collision course with Earth.
In fact, the earth has been hit a number of times by bolides, and so have other celestial bodies: The pockmarked surface of the moon is a vivid indicator of just how many objects have gone zipping around the universe.
Revealingly, the Chelyabinsk bolide took us by complete surprise. We literally didn’t see it coming. So in that sense, Spaceship Earth is flying blind.
Except for one thing: Some humans now have eyes, at least of a kind. With the success of Philae, they can now see the potential to manipulate the course of a comet.
So what might they do with this DDI, this Directed Deep Impact? History affords us no sure answer. But it gives us a warning: We’ll find out.