The Pentagon says it has to shoot down a malfunctioning spy satellite because of the threat of a toxic gas cloud. Space security experts are calling the rationale highly unlikely. "Having the US government spend millions of dollars to destroy a billion-dollar failure to save zero lives is comedic gold," one tells DANGER ROOM.

Yesterday, Deputy National Security Advisor James Jeffrey said the satellite's tank full of hydrazine rocket propellant was the main reason the military was planning to blast the orbiter. There's a small but real risk that the hydrazine tank could rupture, releasing a "toxic gas" over a "populated area," causing a "risk to human life."

But, as we noted yesterday, Joint Chiefs of Staff Vice Chairman Gen.

James Cartwright cast the threat from the satellite in much less dire terms. Even if the hydrazine were released, he noted, the effects would likely be mild – akin to chlorine gas poisoning, which can cause burning in the lungs, and elsewhere. The area affected would be "roughly the size of two football fields [where you might] incur something that would make you go to the doctor."

And that doesn't sound like much of a risk at all.

Especially when you consider that several other hydrazine-filled object have come crashing down to Earth. Not only did the space shuttle Columbia have a similar tank, which survived re-entry, with no toxic gas cloud. Several other hydrazine-laced objects have also crashed into the atmosphere, with no ill effects. Space researcher Ed

Kyle notes that there were 42 major reentry objects for 2007, including 9

satellites – at least one of which contained a form of hydrazine, UMDH (unsymmetrical dimethylhydrazine).

In addition, roughly 8-12 upper stages that originally contained UDMH

reentered during 2007. Some of these could very well have contained some residual propellant. [One particular] upper stage probably contained several hundred [kilgograms] of residual propellant, for example.*

Which leads one military satellite observer to tell DANGER ROOM, "Everything they said made sense except for the reason for doing the intercept in the first place."

"The hydrazine tank is a 1-meter sphere containing about 400 liters of hydrazine. The stated hazard area is about 2 hectares, something like

1/10,000,000,000 of the area under the orbit," he adds. The potential for actual harm in unbelievably small. Which means the hydrazine rationale just doesn't hold up, literally not within orders of magnitude."

"The cynic in me says that the idea that this is being done to protect the lives of humans is simply a feel-good cover story tossed to the media," another veteran space security specialist adds. "It is true that hydrazine is very toxic and could result injury or death, but the odds of this happening are minuscule. The average person in American is many thousands of times more likely to be killed in a car accident than by any falling debris. In fact, no one has ever been killed by space debris (I have heard of one or two being struck but only minor injuries). So pretty much everything else you can think of (including getting hit by an asteroid/comet) is many times more likely than dying from this. Having the US government spend millions of dollars to destroy a billion-dollar failure to save zero lives is comedic gold."

"There has to be another reason behind this," said Michael Krepon, co-founder of the Henry L. Stimson

Center, tells the Washington Post. "In the history of the space age, there has not been a single human being who has been harmed by man-made objects falling from space."

So what could that other reason be?

Our veteran space security specialist believes there are several.

To him, the satellite shot is a chance for the military to try out its missile defense capabilities; a way to keep secret material out of the wrong hands; and a warning to the Chinese, after they destroyed a satellite about a year ago. He shared some educated guesses:

My first thought is that MDA [Missile Defense Agency] is always looking for ways to pimp their systems and provide further justification that they work. The upcoming change in Administration is almost guaranteed to result in missile defense losing the top-level advocacy that it has enjoyed for the last several years. Any additional missions and justifications that the missile defense community can provide would increase the likelihood of their systems (and budgetary power) surviving.

An additional reason could be that destroying the satellite would prevent any chance of another nation getting access to any of the potentially sensitive technology on board. However, I have heard from other sources that supposedly the NRO [National Reconnaissance Office - the country's spy satellite shop] is actually against the

"shootdown" (and I hate that term - the satellite is not flying and is coming down regardless of whether or not it gets hit by a missile).

Their absence at the press briefing could lend some weight to this rumor, although it could also be explained by the nature of the satellite and its still classified link to the NRO.

My real concern is that this is simply a knee-jerk reaction made by the Administration in response to the purported threat by the Chinese.

Since the April 2007 ASAT [anti-satellite] test, there have been rumors and whispers going around that the Administration and like-minded individuals are looking for more sticks (instead of carrots) to use against China.

While this "shoot down" is not a direct action against China, it would be a clear signal that the US can possess an active ASAT capability at any time if it so desires. That is a serious development as the previous US ASAT system using F-15s was mothballed in the 1980's.

There are many significant political ramifications that would happen as a result of this. The US has been berating the Chinese on their ASAT test but now demonstrate that it is okay as long as it occurs at a low enough altitude to prevent long-lasting debris and can

"save lives". This is close to an implied "ok" for the US and other nations to conduct more ASAT tests, which could open another arms race. I am also certain that Russian and China would also see this as a slap in the face as they are trying to revive the Peaceful Uses of

Outer Space treaty discussion and ban on space weapons. It would further negatively affect the relations between them and the US. Which could lead to increased tensions, arms buildup, etc etc etc. Nothing good for anyone outside of arms manufacturers and politicians that need a bogeyman to scare people into voting for them.

Oh, and [NASA Adminsitrator Mike] Griffin's presence at the briefing was also an indicator to me that they are trying to spin this as a safety issue and not a missile defense / ASAT test. NASA has absolutely nothing to do with

US Strategic Command using a Navy missile to blow up a broken NRO satellite.

This is a military/national security op from the start and the only reason you trot the NASA Administrator out is to try and convince people otherwise.

UPDATE: Regardless of the central rationale for the anticipated intercept of a dying satellite, the action almost certainly would offer the Pentagon useful data on conducting antisatellite missions, our own Jeffrey Lewis tells Global Security Newswire.

*The dead U.S. satellite is to be struck at a significantly lower altitude than other space assets. However, that could prove even more of a challenge to the Navy than any future antisatellite operation because spacecraft on lower orbits typically travel at higher speeds,

Lewis said. * The upcoming shot — using a sea-based Standard Missile 3 developed for regional and tactical missile defense — could thus prove to be a useful test for less demanding intercepts that might someday follow, he said. “The higher a satellite is [in space], the slower it moves, more or less,” Lewis said. “This is a perfectly good ASAT test.” ...Asked if it would be fair for other nations to regard the Standard

Missile 3 as an antisatellite-capable weapon if the upcoming mission is successful, Cartwright said it was “a fair question and a good question.” However, he said, the Navy has implemented for this action a

“one-time” modification to the three ships and missiles, which “would not be transferable to a fleet configuration.” For their part, “the Chinese are going to use this to excuse their otherwise inexcusable test,” Lewis said. “And those other countries who we count on to create a norm against debris-creating ASATs will be less willing to help us” in that effort, he said. That said, Lewis added, “maybe they’ll buy the hydrazine story.”

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