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To: AFPhys
Nothing as high as Indium is remotely in danger from this rapidly decaying very-LEO satellite or its even more rapidly decaying fragments. Neither is the Shuttle or the ISS.

Not "Indium" (atomic number 49). Iridium (atomic number 77).

Iridium was so named because the first proposals envisioned 77 satellites in low earth polar orbits (seven planes, with 11 sats in each). It didn't work out that way. Iridium chose six planes, with 11 sats in each, for a total of 66. "Dysprosium" is not nearly as sexy a name as "Iridium" (It sounds like a acid-reflux med). So, Iridium it remained.

The junk propelled by explosion or impact won't necessarily decay all that fast. As one big object, it was a self-contained trash bin which proved no threat to other orbiting objects. But as a shotgun blast of debris it could produce exaggerated orbits of sufficient apogee to take it through the orbital paths of Iridium sats. Probability of impact: P > 0. I would have preferred P == 0.

98 posted on 02/15/2008 11:15:37 AM PST by nonsporting
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To: nonsporting

LOL... oops... wrong element... mind blank... does not change my argument, though, as the more eccentric the orbit of a given fragment, the more quickly that orbit will decay - thus my “100 day risk” suggestion for people to calculate/ estimate.

I am convinced that there is a tendency for people to associate this destruction of a satellite at very low, and dying orbit, with the very different situation of the Chinese killing a satellite at 500miles AGL, in a very stable orbit. The average fragment in that case would remain in orbit for many years... which is definitely not true for this case.

I was not aware of the origin of the Iridium name. Thanks for that story.


99 posted on 02/15/2008 11:47:48 AM PST by AFPhys ((.Praying for President Bush, our troops, their families, and all my American neighbors..))
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