Hi All, Skies were clear last night before the latest storm, so got a good timing on Gorizont 17 (#19765, 89-004A). Flash period continues to go down on this one -- it has now broken under 80 seconds (79.874 +/- .004): From Newport Coast, CA [33.6028 N, 117.8263 W, 200m] (COSPAR 8733) Gorizont 17, #19765 89-004A 01-01-26 06:00:18.0 RM 2156.60 0.1 27 79.874 mag +4 --> inv Some prior measurements: 2001/01/08 80.10 Ed Cannon 2000/10/31 80.82 Steve LaLumondiere 2000/05/03 81.32 Steve LaLumondiere 2000/02/09 81.71 Don Gardner 2000/02/07 81.70 Don Gardner 2000/02/06 81.72 Don Gardner 1999/11/28 82.403 Mike McCants 1999/09/10 82.914 Rob Matson 1999/08/29 82.96 Mike McCants 1999/01/07 83.42 Rob Matson 1998/03/23 84.2 Kurt Jonckheere So, from 1998/03/23 to 2001/01/26 (1040 days), the period has decreased by 4.33 seconds, or .004 seconds per day. However, in the last 18 days, the period has decreased 0.226 seconds, or .0126 seconds per day. No doubt there are some seasonal effects at work, but this is the fastest acceleration ever noted on Gorizont 17 over a period spanning more than a couple days. The data does seem to suggest that December and January are months that bring about the highest angular acceleration on this satellite. Perhaps it is only coincidental that these are the months that the earth is closest to the sun, and solar radiation pressure is highest(?). I will have to look at the data for Superbird A to see if a similar Dec/Jan acceleration peak is present. Cheers, Rob ----------------------------------------------------------------- Unsubscribe from SeeSat-L by sending a message with 'unsubscribe' in the SUBJECT to SeeSat-L-request@lists.satellite.eu.org http://www2.satellite.eu.org/seesat/seesatindex.html
This archive was generated by hypermail 2b29 : Fri Jan 26 2001 - 14:21:38 PST