The first flash was indeed too early, Iridium predictions are
usually very accurate because the satellites are maneuvred to
maintain correct spacing. However, the spare satellites in
lower orbits are not predicted by H-A, though their attitude
-but not timing- is controlled to nearly the same precision.
Rob Matson's SkyMap shows bright flares from these as well,
and his IridFlar program also predicts flares from solar panels,
and can predicted flares by moonlight.
Edited output from IridFlar below, full list attached.
Spare Iridiums are usually denoted by ? in elsets, which
IridFlar copies.
BTW, you forgot to include your coordinates, so I took them
from H-A. According to predictions, the Ir 11 flare was 0.1 km
from city centre. (And if the satellite really were 15 seconds
early, it would have shifted the track by about 5 km)
-- COSPAR 5919, MALMA, 59.2576 N, 18.6172 E, 23 m --
-- COSPAR 5918, HAMMARBY, 59.2985 N, 18.1045 E, 44 m --
-------------------------------------------------------------
Configuration file: carsonct
TLE File: E:\TLE\alldat.tle
Site name: Carson City, NV
Latitude: 39.16400 Longitude: -119.76600 Altitude: 1463.0 m
Time Zone: UTC -7.0 h
Iridium Coordinates Range
Ir# S Date Local Time Azm El RA Decl (km) N Mag
-------------------------------------------------------------
11 ? 2004- 4-23 5:36:50.0 222 74 17h56 26.3 740.4 D 4.1
11 ? 2004- 4-23 5:37:08.1 206 65 18h02 16.5 775.9 D -8.6
11 ? 2004- 4-23 5:37:30.0 197 56 18h08 6.0 843.3 D 4.5
46 2004- 4-23 5:37:10.0 216 72 18h00 24.4 815.2 D 3.7
46 2004- 4-23 5:37:26.9 204 65 18h05 16.1 850.1 D -4.9
46 2004- 4-23 5:37:50.0 196 56 18h10 6.0 920.7 D 4.5
> At 05:35 PST (12:35 UT) I stepped outside to
> observe Iridium 46 flare as scheduled at 05:37:14 PST.
> The flare occurred as predicted (actually it was a bit
> early by 15 seconds). I tracked the satellite
> visually(naked eye) for 17.03 seconds.
> Approximately 1 second later, there was another
> satellite flare in the very same location as the first
> flare had occurred. I need help identifying what this
> second flare was.
> A check at Heavens Above shows Iridium 46 listed
> twice with passes at 05:37:28 and 05:37:29. I was ...
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