Re: FSW-1 decay

Rainer Kracht (
Mon, 19 Feb 96 21:16 +0100

>Date:  Mon, 19 Feb 1996   11:39:11  +0100
>Subject: FSW-1 decay

>The actual decay is almost linear since Aug.-95, with
>superimposed oscillations, with its maximum decay rates
>when perigee is near the equator ( around Jul.26, Nov.04
>and Feb.04). If this were to continue, FSW should survive
>until end of April !

There is a surprising coincidence of Bjoern's dates (of perigee
near the equator) with the dates given by Desmond King-Hele
(in his book "Observing Earth Satellites") for the semi-annual
variations in density during the course of the year (near 250 km
during the years 1972-75, after removal of day-to-night and solar
activity effects).

	Bjoern	King-Hele
	Jul 26	Jul 21  (Minimum)
	Nov 04	Nov 05  (Maximum)
	Feb 04	Jan 24  (Minimum)
			Apr 05  (Maximum)

The density of the atmosphere (near 250 km) is rising in Feb/Mar,
so one would expect an early (March) decay!

 Rainer Kracht   1996 Feb 19
+9.6626E, +53.7695N, 9m