Spy Satellite Shootdown
Wednesday, February 20, 2008; 2:00 PM
High seas in the north Pacific may force the Navy to wait another day before
The attempted shootdown was approved by President Bush last week out of concern that toxic fuel on board the satellite could crash to earth and potentially harm humans, the Defense Department has said.
Ivan Oelrich, vice president of Strategic Security Systems at the
A transcript follows.
Ivan Oelrich: Hello. This is Ivan Oelrich. I am the Vice President for Strategic Security Programs at the Federation of American Scientists. It is a real honor to be here. I am here today to talk about the intercept of the dying satellite.
Eastern Montana: Much has been made about the onboard hydrazine as being the What To Worry About ... making me wonder -- is there a radioisotope package on the satellite generating electricity?
Such a generator would be heavily shielded and so would be much more likely to survive reentry.
Hydrazine seems more like a red herring here ... your thoughts?
Ivan Oelrich: We and the Russians used to put radioisotope generators on satellites in Earth orbit. In fact, many years ago one reentered the atmosphere over Canada and scattered radiatation. Now we only use radioisotope generators in deep space probes, for example, to other planets, not in orbit around Earth. There is no radioisotope generator on this satellite.
Washington, D.C.: If the Navy is unable to shoot down the satellite, will its reentry pose any threat to airplanes?
Ivan Oelrich: Of course, there is some tiny danger. But the Earth is a big place; any given spot has a tiny chance (I am estimating about one chance in a billion, but don't hold me to that exactly) of being hit, and an airplane would have about the same chance.
Washington, D.C.: Why won't this administration tell us WHERE they expect the satellite to impact? We know that they know; why won't they tell us?
Ivan Oelrich:"Why" requires I read minds and I am not good at that. In fact, it is hard to predict where. When a satellite is in high orbit, we can predict very accurately years in advance where it will be, but when it gets into the uppermost reaches of the atmosphere, it gets trickier. And remember, this thing is going 18,000 miles an hour. That is 300 miles a minute. If I am wrong about WHEN it reenters by only a minute, that translates into being wrong about WHERE it reenters by 300 miles.
Philadelphia, Pa.: How many roundhouse kicks would it take Chuck Norris to destroy the satellite?
Ivan Oelrich: Satellites are very delicate, so approximately 17 kicks. The problem is that in space, for ever action there is a reaction and after the first kick, Norris would fly off in the opposite direction.
Harrisburg, Pa.: What are the approximate odds that this satellite will be shot down, and how embarrassing would it be if we shoot and miss?
Ivan Oelrich: The odds that the satellite will be intecepted are high. Although it is traveling fast, the satellite is in a fairly predictable orbit even at this late stage. So the interceptor will know when it is coming. BUT, you can't "shoot down" a satellite. It is not like a hunter with a gun shooting down a duck. BANG! It falls to the ground. The satellite is in orbit and following a trajectory and when the 40 pound interceptor hits the 5000 pound satellite, it will break the satellite into pieces but those pieces will travel, on average in pretty much the same orbit. Some will come down sooner than the satellite would have and some later. The "shooting down" image is in all the news reports but this is nothing like shooting down an airplane.
Alexandria, Va.: Wouldn't it be more practical to launch a satellite that would match orbits with the spy satellite and then destroy it at point blank range with little if any relative motion between them?
Ivan Oelrich: This is precisely how the old Soviet anti-satellite systems worked. So the answer is yes. These are called co-orbital systems. There is some fear that hostile countries might put tiny satellites into near orbits and we would not even know. Then they could be used as anti-satellite weapons in some sort of surprise attack.
Artlington, Va.: ABC says that the satellite is going 22,000 miles per hour (366 miles per minute). I think it is pretty impressive to hit something that is moving that fast. I'd like to be on the Navy ship west of Hawaii when that missile gets launched!
Ivan Oelrich: I think this intercept is a mistake and unneeded but there is no question that the technology is cool. And if the debris reenters the atmosphere where it is night, it will make a spectacular light show, like a slow motion meteor shower.
Reston, Va.: Doesn't the satellite have thrusters it could use to shoot itself out into space?
Ivan Oelrich: Yes, normally. That is precisely the problem. Many similar satellites have been launched and a small amount of thruster fuel is saved for the end and then the thrusters are used to bring the satellite down in the Pacific. The satellite was launched in December 2006 and we lost radio contact almost immediately, so we have not been able to send the signals that would fire the thrusters. Hence the current pickle.
Arlington, Va.: How big is the estimated debris field?
Ivan Oelrich: For a satellite this large, piece might land over an area a hundred miles across and almost a thousand miles long. The debris will actually be spread over a larger area if the intercept is successful (but of course, there won't be any MORE debris, just the same stuff will be spread out more).
Alexandria, Va.: NASA has given assurances previously that the satellite was not a danger. What changed?
Were they wrong? Or is this simply a thinly veiled weapons test?
Do you really believe that scattering space debris across a wide expanse of space in thousands of different directions into unknowable orbits that may present a threat to satellites and manned missions long into the future, is better than letting a lone satellite fall out of the sky?
Sky lab was bigger, no?
Ivan Oelrich: This is a question that not enough people are asking. We lost radio contact almost immediately. At that point the satellite was doomed. But we were told that the danger was minimal. Now, a few weeks ago, the government tells us that they are going to save us from this danger that we didn't even know existed. I believe the public safety argument is hollow. It does not stand up to any sort of cost/benefit analysis. Perhaps that is why the announcement of the intercept attempt was delayed to the last minute. SUPERFICIALLY this looks quite reasonable, a great idea, but it doesn't stand up to analysis. But analysis takes time.
I can't read minds so I don't know motivations but I suspect that one motivation is that this is a great political boost to the missile defense system. People don't make much distinction between missile defense and anti-satellite intercepts. So here is this "grave" danger from space, we fire a rocket at it and, poof, the danger is gone. Aren't you glad we spent the billions of dollars on that missile defense system?
Arlington, Va.: Who exactly owns the satellite?
Ivan Oelrich: It is the property of the US Government.
Hiding Under My Desk: But if the intercept is successful, won't the new smaller (in theory) debris mostly burn up in reentry leaving a smaller actual debris field?
Ivan Oelrich: Depends on how you measure "small." More will burn up in the atmosphere (but not that much more, when the satellite hits the thicker air, it will break up anyway) but even if the smaller debris is spread over a larger area, then the debris field would be larger. It really isn't very important. The important point is the statistical probability that any one big piece will hit anything important on Earth and the size of the debris field doesn't much change that probability.
NYC: Why can't the Shuttle crews go up to the satellite and try fixing it (have they done this)?
Ivan Oelrich: They might have at first but now the satellite is in FAR to low an orbit for the Shuttle to safely operate. And the Shuttle has fixed satellites before, most famously the Hubble Space Telescope.
Remember, each shuttle launch cost close to a billion dollars (as I recall) so it is probably cheaper just to launch another satellite.
Hartford, Conn.: How big is the satellite?
Ivan Oelrich: Everything about the satellite is highly classified and the government is giving few details. But they say it weighs 5000 pounds. I have heard it described as the size of a Chevy Suburban or a small school bus.
Alexandria, Va.: Dear Mr. Oelrich,
With all due respect, safety has nothing to do with why this event is occurring. The general consensus is that the real reason for this shoot-down stunt is to show the Russians and the Chinese that we can destroy their satellites whenever we choose to do so. It has been proven numerous times that the Bush administration will lie in order to achieve political advantage. Why should anyone believe that Bush is telling the truth this time?
Ivan Oelrich: I believe that a reasonably skeptical person can be forgiven that there is more going on here than the administration claims. I too believe that there are primarily political and military motives at work and the claims of concern for public safety are just a cover.
To put this in some perspective, the US produces 36,000,000 pounds of hydrazine every year. The world 130,000,000 pounds. This is transported around the country in trucks and on trains. At any given moment FAR more hydrazine is being shipped on the country's highways, through towns and cities and inhabited areas, than the amount on this satellite. (And far more dangerous materials, like chlorine.) So I do not buy the public safety argument. If the administration were concerned about public safety, they would take the millions of dollars spent on this intercept and spend it on traffic lights at a dangerous intersection or on vaccines for children.
Bethesda, Md.: From the story, it seems that the plan to shoot down the satellite came about only weeks ago ("hurry-up program to adapt the missile for this anti-satellite mission was completed in a matter of weeks"). If this satellite was non-functional and falling why did the decision to shoot it down happen so recently?
Ivan Oelrich: I don't know. But my personal suspicion is that this is superficially a good idea that does not stand up to analysis so don't give people time to think too much about it.
Fairfax, Va.: If I were on a beach in Maui looking up at the night sky (I wish!) would I be able to see the explosion/impact?
Ivan Oelrich: During the day, I doubt it, but at night, you might be able to. If the pieces reentered the atmosphere over you at night, you would definitely be able to see the trail of debris.
Washington, D.C.: So just how much has this whole satelite escapade cost the taxpayer - to build it, send it up, and now shoot it down since it isn't working?
Ivan Oelrich: This is a good question but the biggest cost is the cost of the satellite and that is completely secret. We here at the Federation of American Scientists have a Government Secrecy Project, headed by Steve Aftergood, that has been trying for years to get the intelligence budget published. And recently the government has agreed to publish the entire budget but things like individual satellites are still classified. The interceptor costs $3M. Getting the ship there will cost millions more.
Shoot down like a duck: The duck does not drop straight down. If follows a trajectory, albeit an interrupted and shorter trajectory. I know this from personal experience.
Ivan Oelrich: Your right, but you get my point. In the air, the duck stops flying and falls down, although it does continue forward a bit. A satellite isn't "flying" so the debris will keep going, certainly further than a duck!
Washington, D.C.: It seems to me that this mission is really about either making sure that no one gets their hands on our satellite technology, or testing our capability to do this offensively in the future, or both.
Ivan Oelrich: That was an early theory. The Pentagon has specifically said that is NOT the reason. We have been launching these things for decades and certainly someone has thought that this might happen. Maybe the satellite is specifically designed burn up the super-secret parts. I don't know but maybe.
San Antonio, Tex.:
The news that the shot may be delayed by weather seems strange to me. Looking at current wave height maps, it doesn't seem to be all that bad in the closure area. And the SM-3 missile is an operational military system that, presumably, isn't expected to wait for fair weather before the ship can launch it.
Ivan Oelrich: I just heard this report this morning and it does seem strange. And a little worrying. Does it mean that this system, as an anti-missile system, can be relied on only if the North Koreans fire missiles during nice weather?
Saginaw, Mich.: More on the "toxic fuel," please, commenting on its hazard, survivability, & changes made in powering satellites for both safety & reliability issues.
Ivan Oelrich: The "fuel" or propellant is hydrazine. Chemically it is H2N2H2, somewhat similar to ammonia chemically. Definitely not good to breath but not extremely dangerous. We produce millions of pounds chemical that are more toxic, for example, cyanide, phosgene, chlorine, and others, that are shipped around the country on trucks and trains.
Hydrazine does not provide electrical power to the satellite but powers the thrusters that control the satellite.
Arlington, Va.: China was able to hit a satellite in space several months ago. Will the U.S. use a similar method to reach this satellite?
Ivan Oelrich: The technology the Chinese and Americans use is basically similar. The American system is almost certainly more sophisticated and smaller.
Hartford, Conn.: So what exactly is the "interceptor"?
Ivan Oelrich: The interceptor is a small camera basically, with some jet thrusters. The launch rocket gets it into the right area but not with enough accuracy to actually hit the satellite. The interceptor picks up the satellite and on-board computers calculate the pushes need from the thrusters to put the interceptor right in the satellite's path. When it hits, the kinetic energy is enough to shatter the satellite.
San Diego, Cal.: What are the security ramifications involved in anti-satellite weapons? Is there any way to prevent the loss of our satellites if a hostile country wishes to destroy them?
Ivan Oelrich: It is extremely difficult to protect satellites from attack. That is why I believe that we and the Russians and Chinese and other space-faring nations should work on a ban on anti-satellite weapons.
Blacksburg, S.C: If they miss this object, could it potentially kill anyone on Earth?
Ivan Oelrich: The interceptor is small and they can launch it from a position such that, if it misses, it will fall back into the ocean. That is one advantage of firing the missile from a ship: the ship can move around and get into an optimal firing position.
Annandale, Va.: If we can successfully shoot down this satellite, will we be able to destroy larger meteors (don't want to risk sending a shuttle to set explosives)?
Why don't we ask the Russians or anyone else that has the technology to take a shot at it?
Ivan Oelrich: here is an interesting thought experiment: If we were really only interested in the public safety issue, why don't we invite the Chinese to destroy the satellite for us? I bet if you suggested that to anyone in the government, they would just laugh.
23112: Individually, each reason doesn't seem like a big enough one to warrant a launch, but collectively, you've got a decent sized satellite with a toxic chemical and sensitive technology on board, in a low and decaying orbit that may or may not present a risk to a populated area, and you've got a missile system that the Navy wants to get a practical test launch out of and maybe flash a little techno-muscle. Put it all together, and there's the rationale for the launch. The Pentagon is just being a little obtuse about the why, but I bet FAS is just as curious as a lot of us about what'll happen if that SM-3 hits the bullseye.
Ivan Oelrich: My suspicion is that the public safety is being used at the excuse to do something they want to do for military and political reasons. But I agree, I am a scientist by training and I love this stuff from a technical point of view. The technology is really impressive. I just wish the administration worried more about the international political implications. We should be working toward a treaty to ban anti-satellite tests, not looking for dodgy reasons to conduct them.
Missoula, Mont.: Clarifying an earlier question from Arlington: will this "test" be expandable in to higher orbits? In other words, is the Navy ABM system able to shoot down low-earth orbiting satellites? And is this the same altitude it is expected to hit potential warheads? I gather this satellite is exceptionally low (about to re-enter) and therefore not a true anti-satellite test.
Ivan Oelrich: I have to get going so this will be my last question.
The SAM-3 is limited in how far it can loft the satellite. But intercepting the satellite will be pretty much the same in low orbit or slightly higher. We would need to put the interceptor on a slightly larger rocket but that would be easy.
Ivan Oelrich: It turns out that I have an actual job so I have to get going. This has been fun. A lot of interesting questions. I wrote a piece on the FAS blog, you can see it by going to fas.org and clicking on Strategic Security Blog. I think I am still the first article you will see. It is a great blog!!! Thanks for all the great questions.
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