Decay watch: 2000 May 17

From: Alan Pickup (alan@wingar.demon.co.uk)
Date: Wed May 17 2000 - 14:49:13 PDT

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    I have just posted a (big!) update to my Decay Watch page at
        http://www.wingar.demon.co.uk/satevo/dkwatch/
    with details on the following...
    
    
    #603 = 63- 22 B = Transit 5A3 Scout X-3 r
    
    Final estimates for this decay:
            SpaceCom: May 17 14:19 +-2h near 22.7 S,  61.7 W
            SatEvo  : May 17 13:22 +-45m     10.6 S, 131.1 E
    I estimate that this decayed while northbound over Indonesia, just after
    crossing Australia, though it is possible that re-entry may have
    occurred half an orbit earlier or later near a southbound crossing. My
    estimated elset for the start of the final rev:
    Transit 5A3 Scout X-3 r                          144 x 131 km
    1 00603U 63022B   00138.49809182  .86232800  10141+2  86458-3 0 96329
    2 00603  89.8657 207.1809 0009912 261.4674  98.4202 16.50793972979203
             _________________________________________
    
    #10135 = 77- 61 B = Cosmos 925 r
    
    Final estimates for this decay:
            SpaceCom: May 17 03:49 +-2h near 73.9 S, 139.7 E
            SatEvo  : May 17 03:27 +-40m      0.0  , 111.9 E
    I show decay near a southbound equator crossing over Borneo. My
    predicted elset for the final equator crossing is:
    Cosmos 925 r     3.8  2.6  0.0  5.1 v   11       119 x 112 km
    1 10135U 77061B   00138.11370463  .99587808  22059+2  34006-3 0 97657
    2 10135  81.1809 218.8404 0005878 252.3318 107.6040 16.59086701260186
             _________________________________________
    
    #20338 = 89- 94 A = Molniya 3-36
    
    Current decay predictions:
            SpaceCom: May 19 14:05 +-2d near 56.5 S, 126.7 E
            SatEvo  : May 19 18:34 +-15h
    SpaceCom appears to have lost this for a while yesterday. The latest
    elset has it 4.2 min late on the prediction I made two days ago -
    satisfactory, considering that the orbital period had decreased from
    179.5 to 138.9 minutes in the interval.
             _________________________________________
    
    #22726 = 93- 48 D = InSat 2B Spelda
    
    Current predictions:
            SpaceCom: May 20 00:22 +-2d near 7.0 N, 175.0 E
            SatEvo  : May 20 14:05 +-16h
             _________________________________________
    
    #23098 = 94- 26 B = USA 103 Titan 4 Centaur r
    
    No elsets were available for this until very recently; SpaceCom has just
    posted the first warning for a decay tomorrow.
    Current predictions:
            SpaceCom: May 18 11:44 +-10h near 1.7 N,   1.6 W
            SatEvo  : May 18 11:19 +-6h      61.1 S, 110.4 W
    I put decay near perigee (and southern apex) on the penultimate
    predicted orbit, above. SpaceCom predicts decay a little further only
    near the following northbound equator crossing. If it continues, it
    would cross E Europe from Malta at 11:54 UTC to Kiev at 11:59 and Moscow
    at 12:01.
             _________________________________________
    
    #26114 = 00- 17 B = IMAGE Delta 2 r
    
    Final estimates for this decay:
            SpaceCom: May 17 08:23 +-2h near 43.9 N, 166.0 W
            SatEvo  : May 17 08:03 -10m+2h   19.8 S, 160.6 W
    I show this decaying while northbound over the central Pacific, a little
    before SpaceCom's point. There is a chance that it could have survived
    more than one orbit more if it were subject to the effective decrease in
    drag as its perigee fell through the atmospheric flow transition region.
    It might even have survived to pass southwards over Ireland at about
    10:04 UTC, but the fact that no further elsets appeared seems to rule
    this out. My predicted elset for the final rev:
    IMAGE Del r      7.0  2.0  0.0  5.5 d  7.8       155 x 117 km
    1 26114U 00017B   00138.27811483  .48181565  22297+1  34686-3 0 91461
    2 26114  91.2793 195.0139 0029075 307.5084  52.2276 16.51169022  8044
             _________________________________________
    
    Latest elsets for objects yet to decay:
    Molniya 3-36                                     4871 x 82 km
    1 20338U 89094A   00138.73307815  .59065942  10485-5  11430-2 0  8704
    2 20338  63.4293 350.3374 2703832 247.3169 256.2936 10.42005411 77608
    InSat 2B Splda                                   1053 x 148 km
    1 22726U 93048D   00138.79447615  .12895684 -25790-4  36699-2 0  8702
    2 22726   7.1049 350.8954 0648821 343.5139  14.4386 14.89273654 99095
    USA 103 Titan Centaur r                          2276 x 82 km
    1 23098U 94026B   00138.78498821  .99999999  84829-5  11542-2 0    86
    2 23098  63.0752  51.3885 1451477 256.3785  87.0079 13.21609941  5307
    
    
    Alan
    -- 
     Alan Pickup | COSPAR 2707:  55d53m48.7s N  3d11m51.2s W   156m asl
     Edinburgh   | Tel: +44 (0)131 477 9144     Fax: +44 (0)870 0520750
     Scotland    | SatEvo page:   http://www.wingar.demon.co.uk/satevo/
    
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