Friday, February 22, 2008

Houston: There is no problem

I contend with the previous post on three points: The threat posed by hydrazine was negligible, the U.S. shot NRO 193 for national security reasons not altruistic concerns over toxicity, and the debris emitted from recent explosion are not a significant threat to orbiting satellites.

First of all the idea that thesatellite could kill thousands of people, much less thousands of Chinese, is hyperbole. The odds of it landing in China are slim, and hitting population center slimmer yet. Further, all of the hydrazine would need to survive reentry, and then be distributed in aerosol through an enclosed area. Think falling into Rupp Arena this weekend during the Arkansas game. Again, the chance of this happening is so remote that it makes me want to laugh aloud. On a side note only one person has died from hydrazine, ever.

More info on hydrazine here: ENVIRONMENTAL HEALTH CRITERIA 68 HYRDRAZINE (Seriously check it out! Hydrazine is used to deploy airbags AND its in cigarettes!)

Second, the U.S. did not hit the satellite due to the hazardous fuel it contained but due to the technology this asset possessed. The satellite was launched in 2006 and, logic dictates, that satellite 193 was probably one of the most advanced reconnaissance systems we have launched. An uncontrolled re-entry by a satellite is difficult to predict - there are no guarantees that it would have been completely destroyed during re-entry or that it would land in the ocean. The possibility of a rival military getting a look at some of our treasured technology certainly ruffled a few feathers at the Pentagon and, to soothe their collective nerves, our military officials decided to blow it to tiny bits. This had the added benefit of showing China, Russia, Iran, and everyone else that “Yes, we are that damn good.”

Lastly the threat posed by debris from the missile intercept of satellite 193 is also exaggerated. The U.S. missile strike, as opposed to the Chinese ASAT exercise, occurred just prior to reentry. This means that most of the debris ejected from the strike will continue to de-orbit and burn up. No harm no foul. In contrast, the Chinese chose to hit their satellite, Fengyun 1C, at a comparatively higher orbit. This is much, much worse because it means that the debris will be orbiting in LEO for an inordinate amount of time. NASA has playfully described the Chinese test as “the worst satellite breakup in history”.

You can read more about orbital debris in NASA’s stellar (pardon the pun) Orbital Debris Quarterly: Now on Volume 12!

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