Washington Post Staff Writer
Friday, February 15, 2008 12:00 PM
President Bush, acting on the advice of his national security advisers, has decided to attempt to
And researchers have
Washington Post staff writer Marc Kaufman was online Friday, Feb. 15, at Noon ET to discuss and answer questions about both stories.
A transcript follows.
Marc Kaufman: Good morning, folks. A hot topic today -- Navy plans to shoot down a falling satellite. Let's go to questions.
San Antonio, Tex.:
A back of the envelope calculation shows that the hydrazine hazard area of "two football fields" is less than one ten-billionth (1/10,000,000,000) of the area of the earth under the satellite's orbit. And hazard means everything from eye irritation up through, in extreme and even more unlikely cases, death.
You're at far greater risk every time you drive to the grocery store.
So why is the U.S. taking a fairly extreme action to --possibly -- remove such a tiny danger?
Marc Kaufman: I think it would be fair to say this is a question that many people are asking -- is there another agenda here. The White House says this is all about protecting people from the risk posed by the fuel, while others wonder if this is a way to test our weapons in a real life situation, and to show others -- particularly China -- that we dominate space. What do you folks think?
I-270, Md.: Have the designers of this spy satellite learned why it failed, thereby avoiding a repeat of this kind of malfunction in the future?
Marc Kaufman: All the information about the satellite is classified, so we know very little about why it failed, or even what it is. However, we do know that Boeing won a controversial contract in 1999 to build a new generation radar imaging satellite -- the first such contract of its kind for the company. But continuing technical and financial questions led to a rescinding of the contract. Whether the satellite that malfunctioned soon after takeoff was a result of that contract or a different one remains unknown -- to the public, that is.
Bloomington, Ind.: I remember the United States' criticism of the Chinese after they shot down a satellite. It was said that the resulting debris would make lower earth orbit less safe. Won't the U.S. satellite's destruction do the same?
Marc Kaufman: The shot planned by the Navy would hit the satellite at a much lower point than where the Chinese hit their satellite. Because the Chinese satellite is so high -- about 600 miles -- the debris doesn't descent. Administrator Mike Griffin said that because the Navy shot would be around 120 miles, the debris would fall to Earth --within a day or so, and most of the rest within two weeks. But some scientists I spoke with today said they worried that if the missile hits the satellite, the force of the explosion could sent some debris into higher altitude where it may interfere with the international space station or other spacecraft in the future.
Sterling, Va.: Why will this not burn up upon entering the atmosphere?
Marc Kaufman: The satellite will indeed break up on re-entry. The issue, as described by the military, is that they fear the tank of hydrazine, a rocket fuel, will not break up on its own, and that it will fall to Earth as a whole. They say it would then begin to leak out the hazardous gas. Some scientists find this implausible, saying that they expect the fuel tanks would indeed be breached and would explode on re-entry. But at this point, the military has a monopoly on real information -- what the tank is made of, it's ability to withstand heat and pressure, etc.
23112: Is the shootdown really going to reach the satellite in orbit, or is the orbit decayed enough that it's going to be relatively low and coming down soon anyway?
Marc Kaufman: The plan is to hit the satellite as it approaches the atmosphere, in other words after the orbit has decayed some more. They don't want to shoot while the satellite is still in what they consider to be space for a variety of reasons, and so they are waiting for the final descent. But that doesn't mean the final plunge -- they hope to be ready for a shot by Feb. 20, but they don't expect the satellite to actually plunge to Earth until March 6.
Washington, D.C.: A friend at NASA mentioned that all the boosters that lifted the space shuttles in the last 20 years all fell in the oceans. What if one landed on the ground?
Marc Kaufman: I believe they could potentially cause damage because they are quite large, but their fuel would be gone -- so they probably wouldn't explode. But NASA launches right next to the ocean in part because those boosters can safely fall into the ocean.
Re; Your first post: More to the point, as reported on the news last night, is the fear that pertinent bits of it could fall into the wrong hands, and reveal what we've been up to, espionage-wise.
Marc Kaufman: General James Cartwright was asked about this issue yesterday and said categorically that it did not play a role. But in the world of classified intelligence gathering, clearly, all may not be the way it appears to be, or is said to be.
Greenbelt, Md.: It's really rather sloppy reporting to call this a 'shoot down,' isn't it? The Navy can no more 'shoot down' this vehicle with a Standard SAM than they could keep it in space. The spacecraft is inevitably coming down, irrespective of whether a missile is flung at it or not. 'Shoot down' implies something fundamentally different -- such as what the Chinese did a couple of years ago. So why the misleading and irresponsible Star Wars-Cowboy rhetoric?
Marc Kaufman: Well, the Navy does indeed intend to shoot the satellite down. You're correct that it will be coming down on its own whatever happens, but it seems like a fair characterization to say that the military wants to shoot down the craft instead of letting it fall.
Alexandria, Va.: Isn't there a good chance that we could miss the satellite?
Marc Kaufman: General Cartwright seemed to think the chances were good that it could be hit, though he acknowledged that the missile -- or missiles -- could miss. As China showed last year when it shot down an orbiting satellite 600 miles up -- and the U.S. and Russia showed during the 1980s -- it isnt that hard to hit a "bird" when it's still in orbit. The difficulty increases as it starts to plunge.
Washington, D.C.: If the U.S. government has the capability to potentially eliminate this risk of hydrazine -- I'm not sure I understand why the uproar over attempting to use it. Imagine the reaction if this thing landed in Anytown, USA and hurt, maimed or killed Americans and it was uncovered that the government could have prevented it, but chose not to.
Marc Kaufman: Many people, and seemingly key members of Congress, do support the effort. They agree that the government has a responsibility to limit the risk to people as much as possible.
Those who are skeptical say the chances of the hydrazine tank lands anywhere near people is very, very small. (Three-quarters of the Earth is covered in water, afterall.) In addition, the fuel could be harmful only with substantial exposure, and it is by no means like a chemical weapon. Add to this the military's often-stated concern about protecting space assets and testing ways to do that, and you have some reason for questioning.
Palmyra, Va.: Read your article with interest. Some facts and a question, not necessarily for you.
Fact: Unless someone changed the laws of physics recently, once a satellite is in orbit, it doesn't need any fuel to power it to stay in orbit.
Fact: Unmanned satellites use solar power efficiently and effectively to perform their functions when in orbit. They don't need another fuel source to continue their operations.
Fact: When satellites are launched, one of the objectives is to minimize weight and space.
Question: Why would they need 1,000 lbs. of hydrazene in an unmanned satellite that should use solar power, and take up as little weight and space as possible?
Marc Kaufman: As I understand it, the satellite is launched into a low orbit, and then needs fuel to boost up to a higher one. This satellite lost contact with ground control before that boost took place. The satellites also need propulsion periodically to maintain their orbits, and also to be controlled when they are brought back to Earth.
Washington, D.C.: Why hasn't the danger of hydrazine been a factor in past rocket and satellite launches? Isn't it always used and, if so, wouldn't it be a major risk to humanity if a problem occurs in launching? If not a major risk, what makes this one so different?
Marc Kaufman: In the past, the hydrazine was generally burned up well before the satellite came to Earth. This was also the case when Skylab re-entered and when Columbia broke up over Texas. But I think you may well be correct that this is not the first time that a satellite with tanks still filled with hydrazine lost contact with the ground. So it's a point that we reporters should pursue.
Sterling, Va.: Why will this not burn up upon entering the atmosphere?
Marc Kaufman: The administration says that the hydrazine fuel -- which is frozen solid -- is in a tank likely to survive the breaking up of the satellite as it falls through the atmosphere. They also say it will likely survive a crash landing and will then slowly leak the gas.
Other scientists have told me this seems implausible -- and that the tank would likely break up and then explode on re-entry. At this point, the military has the key information -- what is the shell of the tank made of, how much temperature and pressure can it withstand, etc.
Richmond, Va.: Marc,
How good an idea will the military have of where the remains of the satellite will fall after it gets blasted? Do they want it to fall in the ocean?
Marc Kaufman: They say they want it to fall in the ocean, and I suspect that they will have a decent idea of generally where the pieces will land if they have a direct hit. But because this is an unprecedented effort, there are quite a few unknowns.
Washington, D.C.: If the ulterior motive is to send China a statement, that might explain why we are using Navy Aegis platforms rather than F-15s (as in 1985) or B1 bomber platforms. The Japanese have Aegis cruisers and could probably be outfitted with this intercept technology. That would impress China and North Korea.
Marc Kaufman: Interesting point.
Rockville, Md.: Could a cluster of parts be more danger than one structure? I don't see this as a clear-cut decision.
Marc Kaufman: The parts themselves are not the issue -- nobody has ever been harmed by falling space debris. The question is the hydrazine fuel and whether it would make it to Earth and then leak.
Terrestial Planet Finder: Mr. Kaufman,
The recent discovery of two Jupiter- and Saturn-like planets reminds me of the Terrestial Planet Finder project. This powerful telescope is supposed to be able to actually allow us to see earth-sized planetsaround nearby (within 50 light years) stars.
What's more, I hear it can actually take readings on these planets' atmosphere to determine if signs of life are present. What is the state of funding for this project? Will it ever see the light of day, or in this case, nearby stars?
Marc Kaufman: This question is about another story that ran today -- the discovery of two additional planets in distant solar systems. The writer is referring to a planned telescope that would vastly improve the ability of astronomers to detect faraway rocky planets like Earth. As I understand it, plans for the telescope are on hold, and are expected to remain on hold for some time. There is a raging debate now regarding the NASA budget -- whether it is sufficient to meet the demands, and also how it is divided. The terrestrial planet finder has been a loser in the recent decision-making about which projects should go forward.
washingtonpost.com: 2 Planets Found In Solar System That Is Similar To Our Own ( Post, Feb. 15)
Herndon, Va.: Is this what we would do if an asteroid came? How can the missle fly in space? Will the fins still work?
Marc Kaufman: As I understand it, any danger from an asteroid would be identified years before it arrived in our vicinity, and so any attempts to destroy or deflect it would take place far from Earth (to avoid the space debris.)
Regarding the rocket to be used on the satellite, I believe it doesnt have fins. And it flies in space like any rocket -- with a boost from a lot of burning fuel. These rockets will go as far as their fuel will allow, and then will fall to earth -- unless they hit the satellite first. I havent seen any suggestion that they would go into orbit.
M Street NW, Washington, D.C.: Will we be able to see the satellite explosion from the ground? Naked eye or with binoculars or small telescope?
Marc Kaufman: Very good question, and I'll try to get an answer to be reported in future stories.
Washington, D.C.: This might sound a little Tom Clancy. Maybe the satellite never malfunctioned. The whole operation could be a covert ruse to bluff the Iranians or North Koreans into believing that we already have the capability to shoot down their ICBMs. Such a bluff would be much cheaper than an actual SDI capability. This would be part of a broader plan to discourage them from pursuing ICBM technology.
Marc Kaufman: Doubtful. Amateur astronomers picked up on the botched launch of the satellite in Dec. 2006, and have watched as the orbit has degraded. There may be complex reasons behind the administration's decision to shoot it down, but the satellite is indeed coming down.
Lakeside, Calif.: About what states will the satellite be over when it is shot down? Thanks.
Marc Kaufman: Navy hopes to shoot it down from vessels in the north Pacific, so I presume the satellite would be in that area.
Many thanks for you questions today.
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