Re: 80-008B tumbling? plus a couple of other items

Bjoern Gimle (b_gimle@algonet.se)
Mon, 24 Mar 1997 07:16:46 +0100

Oops - the perils of writing a reply on-line without checking your
figures or formulae. I dismissed the correct formula, because I
calculated /2 instead of *2 :

In message <9703221039.AA25724@cds.plasma.mpe-garching.mpg.de>, I wrote:

>>Q decreases at higher MM. For elliptic orbits, Q is much higher,
>>but seldom more than 2*(16.6-MM)
>
Alan Pickup corrected me:
>Using King-Hele's definitions, Lifetime = Q/ndot
>
>Elsets give you ndot2 which is half ndot, so Lifetime = Q/(2*ndot2)
>
>Q is about about 0.1 rev/day for a circular orbit at 16.2 revs/day MM
>(mean motion). However, at 15.8 revs/day (as per this object) it is
>closer to 0.14 (using King-Hele's graphs).
>Taking ndot2 = 0.00044 and Q = 0.14 about day 97080:
>        Lifetime = 0.14 / (2 * 0.00044) days = 159 days

With the correct definition, Qmax for elliptic orbits should be 16.6-MM.

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