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Re: (meteorobs) Sighting on 2/8/1998 - 19:05 EST
Hi all
>Location of observation: facing the eastern horizon
>Approximately 55 to 65 degrees above the horizon
>
>Location of observers:
>Swedesboro NJ, USA
>45N Degrees Latitude
>75W Degrees Longitude
>
>Apparent movement: from overhead toward North East horizon
>
>Apparent distance of visible travel: 5 degrees
>
>Apparent magnitude: Initially as bright or brighter than Jupiter.
>
>Observing time: maximum of 15 seconds, it could have been as little as 10
>seconds.
>
Then Wayne said :
>If it indeed only traveled 5 degrees in 10 or 15 seconds, it is not likely
>a meteor; atop my list of suspects would be a satellite, particularly one
>of the Iridium series...I'll see if I can impose on a satellite observer
>friend of mine to check out whether such an event was scheduled.
I tried my idirflar DOS program with the approximate location given by the
observer.
This gave me an Iridium flare at 19:01 local time but with a magnitude
around -1. Not at all brighter than Jupiter.
Then I realized that as far as I know, New Jersey is not 45 N.
I went on the web to the tiger map service
http://www.censusdot gov/cgi-bin/gazetteer/
and found this
Swedesboro, NJ (borough)
Population (1990): 2024
Location: 39.74608 N, 75.31278 W
Zip Code(s): 08085
(this is quite a small town)!!!
I then rerun my Iridium prediction program and then :
Configuration file: IRIDFLAR.CFG
TLE File: iridiums.tle
Latitude: 39.74600 Longitude: -75.31300 Altitude: 25.0 m
Time Zone: UTC -5.0 h
Iridium Coordinates Range Sat Solar
Peak Std Maximum Flare
Ir Date Time Azm El RA Decl (km) N Ill Azm Elev M FlrAng
Mag Mag Mag Latitude Longitude
----------------------------------------------------------------------------
------------------------------
13 98- 2- 8 19:00:16.0 027 47 8h21 69.3 1026.8 A Lit 265 -17.4 L 1.86
0.8 -8.1 0.7 39.3817 -75.2378
13 98- 2- 8 19:00:23.0 025 45 8h42 70.8 1056.0 A Lit 265 -17.4 L
0.31 -5.1 -8.0 -5.3 39.7669 -75.2400
13 98- 2- 8 19:00:30.0 024 43 9h06 72.1 1086.6 A Lit 265 -17.4 L 1.75
0.8 -7.9 0.5 40.1520 -75.2418
This gives a -5.1 mag flare at 19:00:23 with Azimuth 025 (NNE) and Elevation
45
I think this what they saw.
I am really used to observing these flares and to a non specialist they
could be taken for a meteor. The main difference to make a good distinction
between the 2 phenomenons is the angular speed which is less than 1 deg/sec
for the Iridium flare.
My best Iridium flares are a -8 mag ones and among those one seen in
daylight.
You will find useful info about these flares at the follwing web page :
http://www2.satellite.eu.org/sat/vsohp/iridium.html
If you can't run predictions programs, I can run other checks about
satellites for the list when required.
Hope this helps.
Jean-Christophe 'Papou' Millot - email : papou@canl.nc
Consultant en Technologies de l'Information - IT Consultant
B.P. 13581 98803 Noumea CEDEX
Nouvelle-Caledonie - New Caledonia (22d17S, 166d28E) UT+11
Tel/Fax/Rep : (687) 27 69 84 - Mobile : (687) 77 19 97