priroda timings

richard.keen@filebank.com
Fri, 26 Apr 96 17:02:36

                                             
 Bill and everyone -
 There seems to be some confusion about how far Priroda trailed
Mir before today's docking.  I believe I saw Priroda twice, and
since I didn't have any elements for the module, I used lag times
(following Mir) computed from the Priroda Rendezvous and Docking
Timeline posted to Seesat by Stu@huston.mdc.com (thanks!).
 Using the following orbital periods, extracted from the
Timeline:
 orbit  priroda  mir
 0      89.837   92.4
 17     90.9
 32     91.9
 47     92.0,
 I computed the following time differences between the passages
of Mir and Priroda past an arbitrary point (the numbers in
parantheses are observed timings):
 Orbit  April  UT    Priroda - Mir (minutes)
 1      23   10.8     69.5
 2      23   12.4     66.9
 3      23   13.9     64.4
 4      23   15.5     61.8
 5      23   17.0     59.2
 6      23   18.5     56.7
 7      23   20.1     54.1
 8      23   21.6     51.6
 9      23   23.2     49.0
 10     24   0.7      46.4
 11     24   2.2      43.9
 12     24   3.8      41.3
 13     24   5.3      38.7
 14     24   6.9      36.2
 15     24   8.4      33.6
 16     24   9.9      31.1
 17     24   11.5     29.6
 18     24   13.0     28.1
 19     24   14.6     26.6
 20     24   16.1     25.1
 21     24   17.6     23.6
 22     24   19.2     22.1
 23     24   20.7     20.6
 24     24   22.3     19.1
 25     24   23.8     17.6
 26     25   1.3      16.1
 27     25   2.9      14.6
 28     25   4.4      13.1    (13, Keen)
 29     25   6.0      11.6
 30     25   7.5      10.1
 31     25   9.0      8.6
 32     25   10.6     8.1
 33     25   12.1     7.6
 34     25   13.7     7.1
 35     25   15.2     6.6
 36     25   16.7     6.1
 37     25   18.3     5.6
 38     25   19.8     5.1   (4.6, Tristan Cools)
 39     25   21.4     4.6
 40     25   22.9     4.1
 41     26   0.4      3.6
 42     26   2.0      3.1
 43     26   3.5      2.6   (2.8, Keen)
 44     26   5.1      2.1
 45     26   6.6      1.6
 46     26   8.1      1.1
 47     26   9.7      0.7
 48     26   11.2     0.3
 49     26   12.8     -0.1
 I know this is too late to help anybody see Priroda now, but
maybe the methodology will help someone in the future.  And,
since it seemed to work (I wasn't sure it would), I'll try to
post similar tables in the future.
 cheers, Rich