new iridiums and more

richard.keen@kingsmarket.com
Sat, 20 Dec 97 20:28:16

                                  
 
 Hi y'all -
 Just had a fun evening, before dinner got in the way.  Started with the sun
just 6 degrees below the horizon, when I observed a string of 5 objects from
this morning's Iridium launch.  Here's the details, by object, followed by the
Quicksat output, with comments after each satellite's predictions:
 
 39.877 105.391 8950.    Coal Creek Canyon, CO 2000 19.0  1 F T F T F
 1997 Dec  21  Sun   UT   033 1325
 H  M  S Tim Al AziC Dir  Mag Dys F  Hgt Shd  Rng  R A  Dec Name
 
 New Iridium objects:
 0 10 20  .0 48  91C 272 20.0   0 5  401 339  521  224 28.0 Iridium, Delta
  5 objects, each mag. 4.5, evenly spaced over a 4-degree length, except the
separation between the 4th and 5 objects was a little less.  7x50 Binoculars. 
I used these elements posted by Ron Lee, and the object train was in the right
place at the right time.
 Date: 12 Dec 1997 From: Ron Lee <ronlee@pcisys.net> Subj: Revised Iridium
Prelaunch Elset
 Iridium, Delta, 20 Dec 97, 13:16 UT
 1 90000U 970XXA   97354.72912400  .00636436  00000-0  81771-1 0    26
 2 90000  86.5832 350.0515 0011476 233.9007 126.1152 14.78783918    32
 
 HST:
 0 27 41  .0 15 168C 270  4.3   3 3  382 359 1021  020-33.9 HST
  mag. 3.5 - a typical pass.
 
 TRMM/ETS-7 objects (all observed with naked eye and 7x50 binoculars):
 0 42  1  .0 31 182C 270  3.5   3 1  246 192  444 2330-19.3 ETS-7 H2 r
  mag. 2-4, tumbling
 0 44 15  .1 28 187C 270  4.1   3 4  219 164  432 2314-22.2 TRMM
  mag. 3.5
 0 49 37  .1 29 187C 270  5.5   3 8  228 161  438 2320-21.3 TRMM H2 db
  mag. 4
 1  8 51  .0 39 186C 270  6.7   3 2  323 194  486 2348-11.1 ETS-7
  mag. 4.5
 
 Here's the ID's and standard magnitudes I used for the TRMM objects:
 25063   97 74A    TRMM            3.5  5.0 4.0 0.0 v
 25064   97 74B    ETS-7           6.2  3.0 0.0 0.0 d
 25065   97 74C    ETS-7 H2 r      3.0 13.5 2.5 0.0 v
 25066   97 74D    TRMM H2 db      5.0  6.0 2.5 0.0 v
 
 Mir:
 0 52 59  .0 44  32C  89 -2.0   2 0  239  78  334  427 66.3 Mir
  Mag. 1 to 0 and yellowish as it came out of the north and passed to the
northeast, brightening to -2 as is sank in the east, with a long flare to
magnitude -4 (and bluish color) before it went into a cloud.
 
 ERBS:
 1 17 13  .0 80 134C 272  2.9   3 8  363 151  368  048 32.5 ERBS
  mag. 4, steady
 
 Cosmos 2228:
 1 29 53  .0 39 265C 268  4.8   3 0  395 267  586 2045 20.8 Cosmos 2228
  Naked eye, flashes to mag. 1 or 2 every 10 seconds or so (I didn't time it);
in 7x50 binocs, magnitude varying wildly between 4 and 8, punctuated by those
flashes.  Spectacular light variations!
 
 Atlas Centaur:
 2 50 13  .0 36 195C 271  4.4   3 4  848 185 1256  057-12.9 Atlas Cent 2
  mag. 4, naked eye.
 00694 t 63 47A    Atlas Cent 2    2.0  8.6 3.0 0.0  13
 
 There's thickening cirrus clouds now (0300 UT), so not much point looking for
the pass of Vanguard 1 in a few minutes.
 Cheers, Rich Keen
 Coal Creek Canyon, Colorado, USA (39.877N, 105.391W, elevation 2728m)