Message posted by Tom on February 20, 2003 at 10:36:21 PST:
There is a group on Yahoo groups (debris-locators)that has been discussing possible shuttle debris along its ground path. It's a spinoff from meteorite hunting. One of the fairly knowledgeable members, Robert Matson, has been doing some ballistic modelling of where some of the initial debris could have landed, assuming the shuttle started shedding pieces over California. A potential zone passes just north of Rachel, and crosses Sand Springs Dry Lake. Remember that this is just one person's modelling, pieces would likely be small (even if they survived re-entry), few and far between, and it's a vast area already littered with unknown aircraft junk. But it would be worth keeping an eye out during travels out of Rachel, as many readers of this forum spend considerable field time in the area. Anything found this far "upstream" could be extremely valuable to the investigation. I've excerpted the pertinent part of Matson's post below: "The only timing clues I've got are John's frame #'s and his remark that the debris was visible for a "second or so", but it's not clear whether that was due to it dimming out or leaving his field of view. For now, I'll bound the possibilities at 1/4-second on the slow side, and 1/15-second on the fast side. The 1/4-second frame rate leads to a ballistic coefficient of 0.148 m^2/kg; the 1/15-second frame rate produces a ballistic coefficient of 2.1 m^2/kg. In either of these cases, we're talking about something rapidly decelerating, which means it has a fairly high surface-area to mass ratio. This is good! If I run the heavier case through my model, the impact point is somewhere between Reveille Peak, NV and a point about 5 miles north of Crescent, NV. There is a dry lakebed about 4 miles north of Rachel, NV that is pretty close to dead center of the footprint. (This prediction does not take into consideration the jet stream; however, I compute that this object would have spent no more than 2 minutes passing through the jet stream's range of altitudes, so the error in impact point would be less than 3 miles -- much less than the overall footprint dimensions.) For the lighter case (corresponding to the 1/15-second frame rate assumption), we're talking about something with the density of a Shuttle tile, so it'll take a lot longer to fall. I'd prefer to wait until I've coded the jet stream model to report predictions, but suffice to say that the impact area will be much closer to the point of release -- somewhere around the Columbus Salt Marsh (Nevada). --Rob"
This severely restricts the area of the impact footprint.
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