Raduga 27 flash period is accelerating!!!

jason.hatton@wanadoo.fr
Thu, 20 May 99 08:51:16 PDT

Hi Everbody,
	Last night (19/May/99) through broken clouds I managed to get another good
timing of the flash period of Raduga 27 (21132/91-14A) ending at 21:15UT
using my 6" telescope. As in my previous observation (9/May/99) the flashes
were relatively bright, around mag+6 & invisible in between flashes. 

	Timing 15 periods I got a flash period of 85.36s +/-0.01s. In comparison
the flash period for my 9th May obs was 89.28s, so the flash period appears
to be rapidly accelerating! This is a bright flasher (at least from my
observing site), so can easily timed even with 10x50 binoculars. It is
currently well placed for southern & eastern european observers. The
flashes are regular & appaer of similar brightness. On interesting features
I noted in my previous observation was some of the flashes appeared to have
a yellow or electric blue tint, although this was less obvious last night
probably because thin cloud reduced contrast.

	As a reminder another bright geoflasher, Gorizont 23 (21533/91-46A) is now
visible from the eastern part of the United States & is slowly drifting
westwards. This satellite is generally a reliable flasher, with mag+5
flashes approximately every 50s, so again this satellite can easily be
observed with bionoculars. If anyone does observe this satellite, please
try to make a timing of at least 5 to 10 flash periods & send your
measurements to the Belgian Working Group for Satellites PPAS address or
post them to SeeSat-L. As Kurt Jonckherre mentioned in a previous post, the
flash period of this satellite appears to vary cyclically throughout the
year, but for some parts of the "curve" there is no observations. If we can
maintain regular observations of this satellite then we might be able to
better understand the mechanisms of these changes in flash period. 

Here are recent elements for Raduga 27 & Gorizont 23

Raduga 27   
1 21132U 91014A   99122.44386755 +.00000124 +00000-0 +00000-0 0 02348
2 21132 005.0880 067.9430 0001320 280.9428 078.9120 01.00182769029967
Gorizont 23   
1 21533U 91046A   99122.43060992 +.00000050 +00000-0 +10000-3 0 01429
2 21533 004.5714 065.0164 0004933 102.3510 257.5586 00.98906201022737

Best wishes & clear skies,

Jason

43.667N, 7.223E,30M