Iridium - Current Status of the Iridial Constellation

From: Walter Nissen (wnissen@freenet.tlh.fl.us)
Date: Sat May 05 2001 - 09:28:17 PDT

  • Next message: Alan Pickup: "Decay watch: 2001 May 5"

    The 66 operating Iridia fly in 6 planes with 11 objects per plane.  The
    current status of the constellation is:
    
    <pre>
    
                  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                 P3 B 51     P4 B 86     P5 B 77
        P0 D 14*    P1 D 20*                             P4 S 911   P5 C 82
        P0 E 21*    P1 S 24*                            P4 T 914    P5 S 920
                    P1 T 71                          P4 V  9*       P5 T 44
                    P2 S 27 <---------<             P5 U 921 <------------<
       P4 ?? 2 <----------------------------------------------<
    
    *   numbers have been confused for these objects and also the "9nn"
        objects.  Be sure to use the unambiguous P-number.
    
    </pre>
    
    Objects in each plane are numbered 0 thru 9 and A.  The objects follow
    one another as shown.  E.g., P01 follows P00 and P20 follows P2A.
    
    Planes are numbered 0 thru 5.  Planes follow one another as shown.
    E.g., P1 follows P0 and P0 follows P5.
    
    From moderate and equatorial latitudes, for planes from P0 to P5,
    objects in one plane skim along the Western horizon as objects in the
    next higher numbered plane go overhead in the same direction as objects
    in the _next_ higher numbered plane skim in that direction along the
    Eastern horizon.  In polar regions, the sky is continually littered with
    Iridia.  From P0 to P5, object Ppo follows object P(p-1)(o-1).  E.g., if
    P22 is low in the West moving Southward, P33 is rising in the North.
    The angle between P5 and P0 is much smaller than the other inter-planar
    angles.
    
    Object numbers followed by R occupy the designated place in the
    constellation, having replaced craft formerly in that place.  When the
    suffix is S, T, U, V, etc., the object has failed and is tumbling.  When
    the suffix is B, C, D, E, etc., the object is possibly on standby,
    available to replace any craft which might fail.
    
    Careful attention to the vertical alignment shows which of the 19
    objects outside of the operating array have moved "out of plane", in
    some cases, far out of plane.
    
    Cheers.
    
    Walter Nissen                   wnissen@tfn.net
    -81.8637, 41.3735, 256m elevation
    
    ---
    
    "If you want to build a ship, don't drum up people together to collect
    wood and don't assign them tasks and work, but rather teach them to long
    for the endless immensity of the sea." -- Antoine de Saint Exupery
    
    
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    This archive was generated by hypermail 2b29 : Sat May 05 2001 - 08:58:10 PDT