Oh what an evening! (Iridium 24, 27 and new Iridiums observed)

Chris Dorreman (bram.dorreman@skynet.be)
Thu, 02 Apr 98 19:06:19 -0000 (UT-)

This evening (March 31), Bram and I observed the Iridium system
in three different ways:

An Ir 24 flare of mag. +2 was predicted for 19.04h UT.
But when I went out a few minutes earlier I saw a -3 flare
almost exactly at 19.00h. It was Ir 24 and using Iridflar we
postdicted the flare. We got the best fit by using the TLE
of epoch 98084.69500837 and replacing N-dot by 0 and N =3D 14.3388.

19.56h UT: an attempt to observe Ir 27 failed.

20.35h UT: we both saw a predicted mag. -7 flare of Ir 32
(I photographed it with a 135mm lens)

20.57h UT: we both observed the new Iridiums
(all steady at mag. +6)
                                          flying this way
Relative positions: *  *      *       *       *  ------->
                    <---- about 20 degrees --->

21.32h UT: an observation of Ir 27 now succeeded. It flashed
to mag. +6. Bram measured a period of about 1.3 seconds but
it was difficult to measure. It often skipped some flashes.

Greetings,
Chris


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 ###    #######   Chris Dorreman - Astronomy
##   ###   #####  51g15'49"NB - 05g28'38"OL
##   ###   #####  http://users.skynet.be/sky56407/html
 ###    #######   bram.dorreman@skynet.be
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