I saw with great interest the predictions issued here by Moritz and Denis. Let me add a few remarks from a view of an old forecaster and analyst: It is absolutely impossible to predict today the decay of the ISS (and also other objects with an estimated lifetime of over 16 months) with an accuracy of better then +/- 5 %. The decay window for a reentry on end of October 2005 would be roughly +/- one month. My friends from the military surveillance community would say: Please work at this time better with a decay window of +/- 10%. The main player in this game is the sun... The reason: You need for a more precise prediction with the Special Perturbation method (SP) a reliable estimate of the solar flux (SFX) and AP development over the next 18 - 20 months. You have the same situation also for a sophisticated Semi - Analytic method (SALT). An error for the mean SFX value of +/- 5% over the coming 18 months produce alone a decay window of about +/- 35 days. The exact value depends from the used density model. In my case is it a modified Jacchia-70 model, nearly identical with the model that USSTRATCOM used. My analysis shows: SP ; 25 October 2005 +/- 40 days SALT: 31 October 2005 +/- 42 days Harro Harro.Zimmer@t-online.de Berlin, Germany ------------------------------------------------------------------------- Subscribe/Unsubscribe info, Frequently Asked Questions, SeeSat-L archive: http://www.satobs.org/seesat/seesatindex.html
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