2004 MN4 – just a few numbers and letters. Couple it with April 13, 2029 – Friday the 13th, however, and you have something just a bit more than a few numbers and letters – the possible end of civilization.
Nobel laureate Luis Alvarez and his son Walter startled the world back in 1980 when they published their findings that a very large near-Earth object had impacted the Earth, and very likely caused the extinction of the dinosaurs and probably nearly everything else about 65 million years ago. Their clear implication was that this could happen again, and that we should use our technology to find potential culprits.
The Alvarez’s spent little time talking about what we should do in the event we found such an object, but they did say that it was worth the effort to look.
When we were concerned with the Cold War (this was back in the 1980s) and the potential destruction of civilization (or even “Nuclear Winter, if you believed Carl Sagan), when we were fighting world-wide HIV-AIDS, when we believed the stock market was teetering, did it really make sense to spend any time on something that apparently had happened 65 million years ago, and that might happen again some time in the future, but that certainly had no immediate impact on anything at all?
Most people thought not, except for a small band of amateur and professional astronomers. These guys “got it” as they say, and perhaps a couple dozen people from around the world have been spending regular time since then looking for and cataloging space objects that have the potential for becoming “near-Earth objects.”
Basically two kinds of space objects can potentially pose a danger to the Earth. Comets are a collection of ice, dust, and gas – something like a large, dirty snowball – several miles in diameter that can cause a great deal of damage should one impact the Earth. Comets are especially threatening, because typically we don’t discover them until nine or ten months before they arrive, which gives us precious little time to do anything about a potential hit. Fortunately, they make up only about 1 percent of the potential danger.
Asteroids, on the other hand, consist of stone and iron (and other minerals and metals). They are usually dense and compact, and they show up much farther out. The asteroid belt between Mars and Jupiter contains literally millions of these objects. Over the years since Galileo first observed the moons of Jupiter with his primitive telescope in 1609 many asteroids have been identified and named, and a significant number have been tagged as near-Earth, in that their orbits bring them near our orbit, although rarely at the same time that the Earth is near by.
Following the Alvarez announcement, this small loosely knit group of astronomers commenced a systematic survey of the heavens to find and catalog potential near-Earth objects. On June 19, 2004, David Tholen spotted something with the University of Arizona's Bok telescope. Tholen and his team got three photos that night and three the next. Then clouds moved in, and they lost it. They reported their findings to the Minor Planet Center in Cambridge, Mass. They calculated that it was 1,000 feet in diameter, and that its chance of colliding with Earth was 1 in 170.
Six months later astronomers in Australia found 2004 MN4 (its new name) again, got several good observations, and refined their calculations. Right after Christmas they announced to the world that 2004 NM4 had a 1 in 38 chance of striking Earth on Friday the 13th, in April, 2029.
But it was Christmas – few listened. And then the Asian tsunami struck, and the world watched in horror as thousands were swept away by the largest natural disaster to hit our planet in many lifetimes. And nobody noticed that twenty-four years out another, far larger disaster was speeding toward Earth along an unalterable track.
Further calculations eventually showed that 2004 NM4 would actually pass between 15,000 and 25,000 miles from Earth – close, but no actual danger.
Brian G. Marsden is the director of the Minor Planet Center at the Harvard-Smithsonian Center for Astrophysics. He oversees the Center’s hunt for near-Earth objects. He said of the near-miss in 2029, “You don't know what the gravitational effect of the Earth will be.” And he went on to explain that, “In 2029, the [close encounter with] Earth will increase the size of the orbit, and the object could get into a resonance with the Earth. You could get orbit match-ups every five years or nine years, or something in between.”
In real terms, this means that 2004 MN4 could come close again in 2034, 2035, 2036, 2037, 2038 or later, and there is no way to predict today exactly what these encounters will be like, because there are too many variables to make any exact predictions.
So, if it does impact, what will happen? Astronomers call 2004 MN4 a “regional” hazard. It carries the wallop of 10,000 megatons of TNT – that is 10 thousand million tons - more than the power of all the world’s nuclear weapons combined. It could take out New England, Texas, or a significant part of Central Europe. If it hit an ocean (which is more likely), it would create the “mother of all tsunamis.”
But it would be survivable for the human race – at least in principle.
So what can we do about this danger? The movies “Deep Impact” and “Armageddon” solved the problem by nuking the intruder into small pieces that would burn up in Earth’s atmosphere. Actually, this is easier to do in a Hollywood studio than in real life. One point made abundantly clear in these movies is that we will have only one chance to solve the problem, which means we had better do it right the first time.
Former Apollo astronaut Russell L. “Rusty” Schweickart is a board member of the B612 Foundation. You may recall that B612 is the asteroid home of Antoine de Saint-Exupery’s “Little Prince.” The modern B612 is a group of space experts that wants to send a “space tugboat” into orbit by 2015, and then dock it with a near-Earth object, and gently alter the object’s orbit by a significant amount – all to demonstrate that we really can do this, so that we really can do it to 2004 NM4 when the time comes.
The European Space Agency also has a small project designed to study near-Earth objects. NASA spends about $14 million yearly on its JPL asteroid database, and for associated research at the Minor Planet Center, and at research centers in Arizona, California, Hawaii, New Mexico and Australia, to catalog and track near-Earth objects.
But nobody except B612 has a plan, and B612 has no money.
The bottom line is that we “know” it’s going to happen, and we absolutely know how to prevent it. But we need to test and refine our methods before it is immanent, or we never will get the job done during the actual emergency – no matter what Hollywood thinks.