Status and Identity of Iridium 30 and Iridium 31

From: Walter Nissen (wnissen@tfn.net)
Date: Sun Jul 20 2003 - 14:22:39 EDT

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    Last fall, Iridium 31 apparently began preceding Iridium 30.
    
    Iridium P29 30
    1 24949U 97051F   02258.91546253 -.00000220  00000-0 -85738-4 0  8857
    2 24949  86.3994  18.8408 0002195  57.6507 302.4894 14.34214726262098
    Iridium P2A 31
    1 24950U 97051G   02259.41018753 -.00000501  00000-0 -18604-3 0  8875
    2 24950  86.3995  18.6190 0002224  61.9927 298.1491 14.34212506262171
    Iridium P2? 30
    1 24949U 97051F   02277.34068691  .00000643  00000-0  22253-3 0  9119
    2 24949  86.4020  11.1598 0001962  83.2909 276.8506 14.34217860264736
    Iridium P2? 31
    1 24950U 97051G   02277.82272857  .00001148  00000-0  40283-3 0  9153
    2 24950  86.4041  10.9316 0002413  76.5065 283.6398 14.34213879264816
    
    I have been hoping for some explanation to be offered, but I haven't
    seen one.  I suppose the minor changes in eccentricity and argument of
    perigee (changes which are better viewed within more elsets) may
    conceivably suggest that STRATCOM or OIG confused the two objects.  Or
    perhaps Boeing swapped them for some mysterious operational reason, a
    possibility I think unlikely (something frequency related, possibly?).
    
    This change is a potential challenge to the logical operational
    nomenclature (see below) in which designations incorporate the order of
    progression of the objects across the sky.  In this nomenclature, object
    Ir P28 is followed by P29 is followed by P2A, with the 11 objects within
    a plane numbered 0-9 and A.
    
    Any thoughts on why the apparent swap?  On what I should do?  If
    desirable, I can easily designate 24950 as Ir P29R 31 and 24949 to be
    Ir P2AR 30; however, the nomenclature will become awkward if many such
    changes are made.
    
    Thanks.
    
    Cheers.
    
    Walter Nissen                   wnissen@tfn.net
    -81.8637, 41.3735, 256m elevation
    
    
    P.S.  In a certain well-known web site this statement appears:
    
    > There are now 6 separate orbital planes of operational satellites
    > spaced approximately 30 degrees apart.
    
    This is not a particularly accurate statement.  There is a substantial
    operational reason for the deviation from perfect consistency in
    separation.  Those of you not familiar with the operational details
    might enjoy puzzling out that reason.
    
    ---
    
                  Structural Diagram of the Iridial Constellation
    
        P00  64     P10  46*    P20  32     P30   5     P40R 84     P50  39
        P01  65     P11  47     P21  33     P31   6     P41  10*    P51  80
        P02  66     P12R 11*    P22  57     P32   7     P42  54*    P52  17
        P03  67     P13  49     P23  58     P33   8     P43  12     P53  15
        P04  68     P14  26     P24  59     P34   4     P44  13     P54  81
        P05  74     P15R  3     P25  60     P35  37*    P45R 83     P55  38
        P06  72     P16  22     P26  55     P36  61     P46  16     P56  41
        P07R 75     P17  23     P27  28     P37  19     P47  50*    P57  43
        P08  70     P18  76     P28  29     P38  34     P48  56     P58  18*
        P09  62     P19  25     P29  30)    P39  35*    P49  52*    P59  42
        P0A  63     P1A  45     P2A  31)    P3A  36     P4A  53*    P5A  40
    
       P0 C 73      P1 B 69     P2 B 90     P3 B 51     P4 B 86     P5 B 77
        P0 D 14*    P1 D 20*    P2 C 91     P3 C 97      P4 S 911   P5 C 82
        P0 E 21*   P1 S 24*     P2 D 94     P3 D 98    P4 T 914     P5 S 920
                    P1 T 71     P2 E 95                             P5 T 44
                                P2 F 96
                                       P5 U 921 <-------------------------<
      P4 ?? 2 <----------no longer to scale-------------------<
    
    *   numbers have been confused (also 9nn numbers), be sure to use P-number
    
    the 2 simulator objects are not included
    the 5 decayed objects are not included
    
    ---
    
    Site of interest:
    http://www2.sis.pitt.edu/~jkabara/tele-2100/iridium/iridium_final.html
    
    ---
    
    The FTC reports that a superficial scan shows 2/3 of all spam evidences
    fraud.  The flood of junk phone calls and junk e-mail has become so
    overwhelming that I'm not merely completely unwilling to place an order
    with that company, but I actively want that company put out of business.
    Now!  What is your ISP doing to stop it?
    
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