Hello everyone, Thanks to good weather I've been able to observe the bright geoflasher Raduga 27 (91-014A/21132) regularly during the last few weeks. After a several months of a deceleration the flash period now appears to be accelerating again. Here are my observations in PPAS format; Decelerating period.... Observing from Approx. 52.7N, 2W, 180M) 91- 14 A 99-12-25 19:31 JPH 737.0 1.0 8 92.1 F'F' vm mag+7->inv 91- 14 A 99-12-28 18:20 JPH1304.9 0.2 14 93.21 A'A' mag+6->inv 91- 14 A 00-01-01 18:04 JPH1136.8 0.5 12 94.73 A'A' mag+6->inv >From 43.692N, 7.246E,30M 91- 14 A 00-01-23 18:16 JPH1412.2 0.2 14 100.87 F'F' mag+6->inv Acceleration starts.... 91- 14 A 00-02-04 21:21:09.1 JPH1836.4 0.2 18 102.02 A'A' vm mag+8/10->inv 91- 14 A 00-02-09 20:42:55.3 JPH1325.3 0.2 13 101.95 A'A' mag+8->inv 91- 14 A 00-02-10 20:22:04.4 JPH2445.1 0.2 24 101.88 A'A' mag+8->inv 91- 14 A 00-02-12 20:25:09.9 JPH2542.9 0.2 25 101.72 A'A' mag+8/+11->inv 91- 14 A 00-02-13 03:12:53.6 JPH2746.5 0.2 27 101.72 A'A' mag+6/+9->inv 91- 14 A 00-02-13 19:40:56.9 JPH2337.4 0.2 23 101.63 A'A' mag+8->inv 91- 14 A 00-02-16 19:43:42.2 JPH 810.6 0.2 8 101.33 A'A' mag+9->inv 91- 14 A 00-02-17 19:30:29.8 JPH2024.4 0.2 20 101.22 A'A' mag+8->inv 91- 14 A 00-02-19 18:34:31.5 JPH1994.8 0.2 20 100.88 A'A' mag+8->inv The flashes are only visible during a period of approximately 80 minutes, with the period of visibility starting approximately 12 minutes earlier each day; 13-Feb-2000 1st flash seen = 19:02UT, last flash = 20:20UT 16-Feb-2000 last flash = 19:44UT 17-Feb-2000 last flash = 19:32UT The flashes are intially visible at approx mag+10, brighten to mag+8 in the middle of the zone of flash visibility before fading away again. Question: Can these data be used to determine the rotation axis of satellite & is there anyone on the list who knows how to make the calculations? Interestingly, a second series of flashes are visible in the early morning, which can be as bright as mag +6 (eg. 13-Feb morning observation). A quick glance at my Skymap finder charts suggests the period of flash visibility may correlate with the declination of the satellite. Raduga 27 is in a 5 degree inclination & so appears to drift north then south during the day. The evening flashes occur when the satellite is drifting northwards, whilst the morning flashes occur when the satellite passes through a similar declination on its way south. Additionally, the flashes observed in December & January might consititute a third series of flashes, given the period of visibility of the current "evening" flash series. All in all quite an interesting object to observe! Here is a recent element for Raduga 27: Raduga 27 1 21132U 91014A 00046.71327620 +.00000120 +00000-0 +00000-0 0 02943 2 21132 005.6418 065.9041 0005312 202.4570 157.6642 01.00311841032860 Best wishes & Clear skies, Jason Jason P Hatton 06200 Nice France 43.692N, 7.246E,30M (43d41'29"N,7d14'47"E,30m) http://www.geocities.com/CapeCanaveral/Hangar/1668/high-alt.htm ----------------------------------------------------------------- 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 : Mon Feb 21 2000 - 11:43:53 PST