Iridium flares, 30 Aug 97
Ed Cannon (ecannon@mail.utexas.edu)
Fri, 26 Sep 1997 01:20:58 -0400
Late Iridium flare report. Mike McCants and I were observing at BCRC,
Austin, Texas: 30.314N, 97.866W, 280m; August 30, 1997, UT (8/29/97
local time). Where I don't have the time of maximum flare, I've used
an approximate time in order to get the approximate solar azimuth and
elevation.
NORAD __date__ __time__ Dir azI eI azM eM azS _eS Phs Dur Mag Obs COSPAR
Iridium 5:
24795 97-08-30 02:09:40 S 145 31 083 51 291 -16 146 ... -2 E/M 97020D
(Data thanks to Mike, who noted time of max, which might have been -3.)
Iridium 6:
24794 97-08-30 02:18:-- S 084 64 292 -18 +2 E/M 97020C
(I don't have the time of maximum flare.)
Iridium 7 (no flare):
24793 97-08-30 02:27:40 S 085 81 294 -20 ? E/M 97020B
(We tracked Irid. in Mike's 8" scope; at given time saw UNID in field.)
Iridium 8 (no flare):
24792 97-08-30 02:36:-- S 266 81 295 -21 +6? EdC 97020A
(My only note was that I tracked it in my 7x50 binocs.)
Very late report format suggestions (many apologies to Ron!): one space
only between fields (It does that on the hypermail archive anyway; all
extra spaces are lost -- but see further note on this below.); four
characters for year (Y2K); only 1 char for Direction; 4 chars for
Observer(s) (E.g., Sue and I saw one, and Mike and I saw another.) or
that exact location number that some people use; 2 chars for Iridium
number. This totals only 75 characters, e.g.:
NORAD ...date... ..time.. D azI eI azM eM azS elS Phs Dur Mg Obs. COSPAR IR
24795 1997/08/30 02:09:40 S 145 31 083 51 291 -16 146 ... -2 ECMM 97020D 05
........10........20........30........40........50........60........70.....
123456789 123456789 123456789 123456789 123456789 123456789 123456789 12345
I realized (last of all?) that the Sun's azimuth reveals AM or PM....
So, if the observer doesn't get an exact value for that, the values 90
for morning and 270 for evening could be used. (I understand those
directions are very rough approximations in winter and summer for high
latitudes.)
Are slashes okay in the date?
I really do think that for *Iridium* flares, the only identifier needed
for the satellite is "i4, i15, i26, i37," etc., or something like that,
with a table of correspondence available that links those to NORAD and
COSPAR.
(Note on the hypermail archiver(s): could it/they could be changed to
simply enclose the entire body of all messages in <PRE></PRE> tags?
That would fix the layout problems on the hypermail archive that are
caused by the removal of all extra spaces and the use of proportional
fonts.)
Theoretical Iridium flare question: Since they may flare to -8 and
apparently always flare opposite the Sun, what are the chances -- if
any! -- of observing a flare while the Sun is above the horizon
(especially if they prove to be reasonably predictable)?
Ed Cannon
ecannon@mail.utexas.edu
Austin, Texas, USA
30.3086N, 97.7279W, 165m