Tonight between 02:30 and 05:00 UTC (6:30 PM and 9:00 PM central time), the US Navy will fire a series of SM3 (standard missile 3) interceptors at a disabled National Reconnaissance Office satellite. The satellite went out of control several weeks ago, and is currently spiraling down into the atmosphere. Without any intervention, it will re-enter sometime next month. The satellite is supposedly “the size of a school bus” and may weigh “upwards of 20 tons.” The Bush administration, with agreement from the Pentagon (or at least the civilian side) and NASA (or rather, NASA’s chief administrator), has chosen to accelerate that timetable. They argue that the satellite’s propellant tanks, which contain a small but dangerous amount of hydrazine fuel, could survive re-entry and hit the ground, releasing the hydrazine in a populated area. This is apparently Very Bad, and so we are going to shoot it down. Now, let’s examine these assertions one by one.

First, what is the National Reconnaissance Office? The NRO is basically NASA’s spoiled little brother. They build spy satellites. They have a budget of about $7 billion a year to do so, and they do it…. err… poorly. Like most military space programs, NRO programs are often over-budget and behind-schedule. Sometimes billions of tax dollars are spent and no functional satellite is built. In 1996, the NRO “lost” four billion dollars of their budget. The NRO definitely serves a useful purpose. Military spy satellites allow us to keep tabs on our enemies…and our allies. They are doing the same to us. That’s a good thing. As long as we know exactly what, say, China and Russia are building, and they know exactly what we have, it is a lot easier to trust each other. However, the NRO’s cost control and reliability are very poor. This is the same criticism that many apply to NASA, and that is true in some ways. However NASA makes the right choices almost all the time, in fact far more often than any other agency with such broad responsibilities, but the NRO’s record isn’t so great.

Second, what is an SM3? The SM3 is a theater anti-ballistic missile weapon launched from a cruiser, frigate, or destroyer equipped with the Aegis anti-missile radar system. It is designed to intercept intermediate range ballistic missiles in the boost phase. After much money spent by every President since Reagan, it works. Quite well, in fact, but only against preplanned targets in controlled test situations. The SM3 does not have the range to be used as an anti-satellite weapon except in situations like this one where the satellite is already about to crash. However, this low-flying satellite target makes the Navy very happy, because they get to test their missile against a target that is moving much faster than the usual test subjects. They get more data to improve their missile this way.

Next, the satellite. First of all, it is not the size of a bus. It may look that big with the solar panels extended, but those will fall off and burn up as soon as the satellite enters the atmosphere. It’s more like the size of a small hybrid car. Second, this satellite does not mass 20 tons. It’s more like two and a half tons. Most of that will burn up on re-entry, leaving only a pieces massing a few kilograms each to reach the ground. That will happen whether we shoot it down or not. I hope none of them fall on your head. However, we know from the Columbia disaster in 2003 that lightweight, heat resistant components like fuel tanks often survive re-entry. There is a risk that the hydrazine propellant tank will survive all the way to the ground and then crack open, contaminating an area… about one hundred meters square. And make people sick enough that they will “want to go to the doctor” (I owe you a citation for this, it’s from Aviation Week and Space Technology two weeks ago). However, if we can hit the satellite with a kinetic-kill missile, we might be able to crack the fuel tank open so that it leaks out into the upper atmosphere, where the hydrazine will burn up and harm no one. OK, that’s very true. However the risk from a tank full of hydrazine is very low, unless it lands in the middle of New York City. And that is not likely. The public safety argument for intercepting the satellite is not valid. Neither is the national security argument. Anything sensitive aboard this satellite will be burned up in the atmosphere, missile or no missile. All we’re getting is a tank of fuel.

Next, who is behind the decision to shoot down this satellite? President Bush, for one. He wants to show the American people that the missile defense system he has poured money into and lapsed a treaty for actually works. Of course, there is a risk that it won’t work and he’ll be embarrassed, but he’s willing to take it. Fair enough, although flawed, because intercepting this satellite will do more harm internationally than lapsing the ABM treaty in the first place. Second, the Pentagon. But who in the Pentagon? The Air Force and Navy are generally against the weaponization of space. They believe in protecting space assets, but not with weapons. After all, if protecting your satellite costs more than the satellite, why bother? Instead, the Air Force is a big proponent of “operationally responsive space,” a doctrine in which small, inexpensive satellites are prepared for launch at a moment’s notice. So if we lose a satellite, we just put up another one. It’s cheaper, faster, more reliable, and doesn’t create big clouds of debris (see The Space Show, a couple weeks ago, interview with guy from Air Force Research Lab) . Ironically, this particular satellite is a prototype for operationally responsive space! (Aviation Week and Space Technology online, February 17, here). So who in the Pentagon favors this test? Civilian analysts! And MDA, the Missile Defense Agency. They want to test their hardware. What about NASA? NASA is a civilian agency, why are they involved in shooting at a defense department satellite? Well, they’re not, not really. Michael Griffin, the chief administrator of NASA, is basically a Bush yes-man. He’s very intelligent and usually makes good engineering choices, but he’s a Bush hard-liner. More importantly, he was part of the team that built and tested the first US anti-satellite (ASAT) weapon in 1985. He was not connected with NASA at the time. So it’s not NASA’s expertise Bush is counting on, it’s NASA’s good public image for being smart, and Griffin’s personal expertise.

So we have a satellite that isn’t really a threat being shot down by a missile that needed testing anyway, thanks to a decision by the president, a bunch of civilian analysts, and Michael Griffin (which means Bush). Why bother? Well, for one thing it lets us stick our tongue out at China, who conducted a much more dangerous test against one of their own satellites a year ago. That satellite was flying much higher, and so the debris from that test will take centuries to come down. The debris from our test will re-enter in hours to months, and pose little threat to anyone. Good choice of target, I suppose. However, if we conduct this test, we will further alienate Russia and China. China argues that their ASAT test was just to make a point about the danger of ASAT weapons. For the laymen out there, let me explain the concept of a debris cascade. Basically, the more objects you have flying around in low earth orbit (LEO), the more likely they are to collide. When they collide, they fragment. Then you have more things flying around on unpredictable paths. A tiny little screw or fragment of an antenna, moving at several kilometers per second, can destroy a multi-billion dollar satellite or kill somebody. This is bad. The more debris you have, the more collisions you have, and the more debris you get. Eventually you have a cloud surrounding the Earth, and then you can no longer launch satellites! No more weather satellites, no more comsats, no more imaging, no more internet in third world countries, no more research…OK, we don’t want that. Granted, this particular test does not pose the risk of a debris cascade. However, it is a bad precedent. The last thing we need is an arms race in space. The long term consequences of repeatedly testing these things could be more dangerous than above ground nuclear testing. Nuclear tests make people sick. ASAT tests could permanently blind the world. China did something very stupid last year. Let’s not repeat their mistake, and make it more likely that someone like India, the European Union, Russia, or Israel will follow up on our act and make the problem even worse.

I’d like to say “I hope we miss.” But I don’t. Because if we do, the public will irrationally blame NASA, which really has nothing to do with this. I wish we weren’t doing this. It’s just stupid. It’s a political move to make us look tough versus China, to give the anti-ballistic missile system good public relations, and an engineering move to test the system against a harder target. If we had signed the ASAT ban that Russia and China proposed recently, we wouldn’t have to do any of these things. I can only think of one good thing that can come out of this. Barack Obama now knows what the National Reconnaissance Office is, and maybe now he will cease telling the public that he plans to use NASA to spy on people for national security reasons. If he’s going to be president, it will be good for him to have his agencies straight. And you, like Senator Obama, will know who is responsible and not blame NASA. NASA doesn’t spy on people or shoot at things. NASA does research and develops technology to improve peoples’ lives. The NRO builds spy satellites. Their job is indeed necessary. They could certainly do it with better cost control and reliability. The Air Force thinks ASAT weapons are stupid. Pentagon civilian analysts think they’re incredibly cool. Bush wants good PR. Michael Griffin will do whatever Bush wants, but he’d like this to be over so he can go back to doing useful work, which he is actually very good at.