Re: How close to decay?

Alan Pickup (alan@wingar.demon.co.uk)
Wed, 7 May 1997 19:30:59 +0100

In message <1.5.4.16.19970507093557.0e0fa468@mail.utexas.edu>, Ed Cannon
<ecannon@mail.utexas.edu> writes
>The following three objects, which I don't think I've seen in decay 
>predictions, have pass predictions below 320 km (200 miles) over 
>Austin in the next week.  I wonder how close to decaying they are.
>
>13985   Satcom 6 Rk    83 30B
>1 13985U 83030B   97125.59090769 +.00012750 -62377-5 +24813-3 0 06421
>2 13985 025.3439 253.2129 1146625 004.2044 356.7184 13.29029674620710

A straight extrapolation from the average drag over the first four
months gives this a lifetime of about 25 years. To last this long,
however, it would have to survive the increased atmospheric density
during two solar maxima (due in perhaps 2000 and 2011) - I don't think
it will. My guess is for decay around 2010.

>
>21892   GPS 2-12 PKM   92  9C 
>1 21892U 92009C   97127.17395889  .00480177  52067-6  11916-2 0  8271
>2 21892  34.4943  38.7019 3092378  81.5328 311.8759  9.41525898113255
>

An easier one this. Decay in 1998 April, give or take a month or 
three. :-)

>22583   GPS 2-19 Rk    93 17C
>1 22583U 93017C   97125.69345198 +.00012018 +23404-5 +19695-3 0 01321
>2 22583 036.1726 227.8344 0462079 040.4307 322.9820 14.83150613218383
>

My guess is year 2000.

Alan
-- 
 Alan Pickup | COSPAR site 2707:  55d53m48.7s N   3d11m51.2s W  156m asl
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