hello, This evening (Feb 28), I had Gorizont 23 in the eyepiece from 18h36m05.2s. At that time it was surpringly dimmer that Saturday evening, with flashes to mag +9.5 only. The next minutes it even started becoming fainter and became hardly visible at mag +11 at 19h09m21.7s, still flashing every 51 second. After that I lost it for some minutes and found it back very faint from 19h13m11.8s on again flashing every 51 second. I have to admit that maybe I missed the start of the second sequence of flashes, because when observing faint objects I cannot concentrate long looking through the eyepiece and look away from time to time. Afterwards during the analysis, it became clear that during the minutes I lost it a PHASE SHIFT had occured (see the time difference of 230 s = 51.2 * 4.5 periods), every flash seen after that occured half a period later ! I checked this fascinating object again later this evening and now it was again easily visible with binoculars at mag +6 around 21h19m. All flashes were from the "after phase shift" series. Conclusions from one observation station : 1. Gorizont 23 becomes fainter after twilight from mag +9 to about mag +11 2. Then a phase shift occurs (on Feb 28 at 19h11m +- 2min) 3. afther that it starts to brighten (see observations of Saturday and today) from +11 to +6 after 21h UT and maybe brighter later. This all needs to be checked by others in France, Scandinavia, and within some weeks America... I have seen this object many times and checked back my observation log to find that during my first observing night with my Dobsonian on Dec 16, 1997 I also a phase shift somewhere between 17h58 and 19h16m... All other times, nothing special was seen. I also received some obs from Jason Hatton (Southern France) confirming the current very slow acceleration. (see below) Kurt Jonckheere wrote: > Gorizont 23 = 91- 46 A = 21533 = slowly drifting > geostationary sat is visible over Europe again > so I decided to take the telescope and found that around 19h20m > it was flashing to only mag +7.5 or so. Fainter than usual. > to try binoculars again (from 21h20m UT) and yes indeed, now it > was easily visible around magnitude +5.5. Recent observations (view with courier font or so): 91- 46 A 00-01-15 08:22 SDL4418.1 0.2 86 51.373 91- 46 A 00-01-19 07:00 SDL3594.5 0.2 70 51.35 91- 46 A 00-02-17 19:59:02.2 JPH1178.2 0.2 23 51.23 A'A' mag+5->inv 91- 46 A 00-02-19 19:28:14.1 JPH1536.4 0.2 30 51.21 A'A' mag+6->inv 91- 46 A 00-02-23 20:40:17.9 JPH1843.2 0.2 36 51.20 A'A' mag+6->inv 91- 46 A 00-02-25 PDV 60 51.18 91- 46 A 00-02-25 MJ 2610.6 0.02 51 51.19 2 series of obs 91- 46 A 00-02-26 19:50 KJ 51.197 +-0.002 mag +7.5 91- 46 A 00-02-26 21:35 KJ mag +5.5 91- 46 A 00-02-28 19:00 KJ 51.195 +-0.002 mag +11 91- 46 A 00-02-28 21:15 KJ 51.193 +-0.002 mag +6 [Stephen D LaLumondiere, Jason Hatton, Patrick De Vreese, Michel Jacquesson, Kurt Jonckheere] have fun!, Kurt Jonckheere (kjon@mail.dma.be), 3 degr, 44 min E, 51 degr, 2 min N observations collector for the Belgian Working Group Satellites. ----------------------------------------------------------------- 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
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