Some Friday night obs, and Iridium rockets
Ed Cannon (ecannon@mail.utexas.edu)
Sat, 07 Feb 1998 02:55:33 -0600
Observing from Univ. of Texas at Austin campus, 30.2835N,
97.7379W, and about 150 meters elevation, among the 10 objects
I saw using one-power (beautiful evening!) were:
TRMM (25063, 97-74A) -- After its culmination, it went through
Orion, north of the belt. At that point it was comparable in
magnitude with Bellatrix, the belt stars, and Saiph (gam, del,
eps, zet, and kap Orionis), from +1.64 to +2.23. Higher up, it
was brighter than those but -- oh, the failing memory! -- I
think it did not get as bright as Aldebaran (+0.85), so maybe
it reached about +1.0 to +1.2.
25044 (97-69F; the [Delta 2] rocket of the seventh Iridium
launch, which maybe is a reason to call it "Iridium L7 Rk" [See
more below.]) -- It was near perigee on a high pass east of the
zenith, moving really fast. At culmination it was only about
275 km (172 miles) distant, and only about 250 km (156 miles)
above the ground. It appeared steady and reached about mag.
+0.5 to +1.0. Fun!
UHF F1 Rk (22564, 93-15B) -- flashes between +1 and +2; period
approx. 18 seconds.
TRMM/ETS7 Rk (25065, 97-74C) -- brighter than +2 at maxima; saw
two maxima before it entered shadow.
-----
Regarding the "common" or "vulgar" names (for use in TLEs, etc.)
of Iridium launch vehicles -- The upcoming launch, which is
Boeing Delta Mission 7, is really the *tenth* launch. I'd like
to propose the following naming scheme for the Iridium launch
vehicles:
Launch Date Cat # ID Name(1) Vehicle St.
------ -------- ----- ------- ----------- ------- ---
01 97-05-05 24797 97-20F Irid L01 Rk Delta 2 o
02 97-06-18 (2) 97-30_ Irid L02 Rk (2) (2)
03 97-07-09 24874 97-34F Irid L03 Rk Delta 2 o
04 97-08-21 24908 97-43F Irid L04 Rk Delta 2 d
05 97-09-14 24951 97-51H Irid L05 Rk (3) d
06 97-09-27 24970 97-56F Irid L06 Rk Delta 2 o
07 97-11-09 25044 97-69F Irid L07 Rk Delta 2 o
08 97-12-08 25079 97-77C Irid L08 Rk CZ 2C d
09 97-12-20 25109 97-82F Irid L09 Rk Delta 2 o
10 98-02-__ 25___ 98-___ Irid L10 Rk Delta 2
etc.
St. = "Status" as of 98-02-07
o = In orbit
d = Decayed
(1) "Rk" or "r" (Molczan) or "R/B" (OIG) are interchangeable.
(2) Proton (= SL-12?). Apparently it was never cataloged. The
seven Iridiums it launched were cataloged in Mike McCants'
message "satwk26.rpt from OIG". I guess it decayed the same
day, as did L05 (24951).
(3) "SL-12" (= Proton?). It decayed the same day. Do these not
have any stage that stays longer in orbit?
Ed Cannon
ecannon@mail.utexas.edu
Austin, Texas, USA