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Observational Flashes

Observational Flashes is open to short observational contributions by all observers. English language texts are preferred, but short (!) Dutch, French and German language items will be translated if received. Observational flashes are sometimes edited by BDP, so any language errors are his responsibility.

Mike McCants, Austin, Texas

I saw 85- 41 B on January 15. It was almost steady at first. Then it started showing variation (flash period 17.3 s). Then a secondary max appeared. One secondary max flash to mag 4.

On Dec. 25, I saw 94- 77 B with 0.393 seconds. Near culmination, alternate maxima were a quick double flash.

On November 21 I saw 90- 4 B with a period of 70 seconds. I wonder if it's accelerating? On the same day I saw 93- 1 B with a period of 40 seconds. Observed as approximately 50 seconds on Nov. 18. I wonder if it's accelerating? 87- 98 B seems to be holding constant at 39.3 (on Nov. 21).

79- 30 B showed strong secondary maxima - alternate secondary maxima was a sharp flash. It continues to decrease down to 4.56 seconds (on Jan. 28).

One day later 84- 35 B had a period of 10.7 seconds. Timed first min of a double min. Went into shadow. It must be pretty big to be so bright at 5800 miles. Here are some elements :

1 14900U 84035  B 95018.33146350  .00000002  00000-0  10000-4 0  4815
2 14900  30.7392  65.6788 7188175 151.6180 280.9798  2.30934786 24369
I saw a GPS at 12000 miles at about 11.5 magnitude or so.

Alex Seidel, Stade/Elbe, Germany

On February 3 at UT 5.44, just 22 minutes after launch watched live in the TV morning news, I was able to observe Shuttle Discovery (mission STS-63) from my home in Stade near Hamburg, passing southbound some 25 degrees over the SSW horizon. It was accompanied by another object, obviously the external tank separated over the Atlantic, trailing about half a degree below and behind, and maybe some 1.5 magnitudes or so fainter in brightness. Visibility conditions were very poor due to a rather hazy and partly cloudy sky at the time of transit, so a brightness guess cannot be given better than what might have been around mag 0 to -1 for the main object, fading rapidly down with decreasing phase angle in the SSE. At the same time it must have been quite a spectacular sight from clear sky locations nearer to the groundtrack (Northern France ->Southwest Germany -> Austria). Thanks to Bart who drew my attention to this launch via the ESOC phone chain a day earlier - otherwise I would have possibly missed the whole exciting thing...

Ryan Rudnicki, USA

Yesterday evening, Feb. 1, I happened to catch what appeared to be Cosmos 1953. This satellite was most distinctive because of its rapid flash rate. I was really looking for Cosmos 1726 which was passing to the north at virtually the same time. Never actually saw it. I was distracted by Cosmos 1953. Near its culmination, Cosmos 1953 reached about mag 2 every 6 to 8 seconds. Then it would fade to below eye visibility level which around here is around mag 3.5 or 4. Cosmos 1953 is 88 50A, norad 19210.

Walter Nissen, Berea, Ohio, USA

Whoops! Didn't I mention C* 1953 at some point? It is presently one of the more spectacular objects in the C* 1933 family. If there are no earlier reports of flashing, then the ones below tell a very, very interesting story. And I am embarrassed for not (?) reporting it.

The location shown below is a remeasured value for the same location I have been using since mid-1994. I actually have two sites separated by about 10m.

Walter I. Nissen, Jr., CDP,, 55 Barrett RD #808,
Berea, OH 44017-1657, USA, 216-243-4980, -81d 51.823', 41d 22.413', 256m, 7x35

88- 50 A 94-11-10 11         WN     S                  C* 1953, S, poorly seen
88- 50 A 94-11-12  0         WN     S                  C* 1953, S, mag 3? at C
88- 50 A 94-11-13 23         WN     S                  C* 1953, S
88- 50 A 94-11-14 10:57:20   WN     S                  C* 1953, S, except:
88- 50 A 94-11-14 10:59:39.3 WN                        C* 1953, mag 3? F!
88- 50 A 94-11-14 11: 0:34.5 WN                        C* 1953, sudden dis
88- 50 A 94-11-17 10:16:45.6 WN  147.3 0.8  34  4.33   C* 1953, incredible,
                                                       irreg, bright Fs
88- 50 A 94-11-19 10:54:49.4 WN    4.4 0.8   1  4.4    C* 1953
88- 50 A 94-11-19 10:54:53.8 WN    4.1 0.8   1  4.1    C* 1953
88- 50 A 94-11-19 10:54:57.9 WN    2.8 0.8   1  2.8    C* 1953
88- 50 A 94-11-19 10:55:  .6 WN    1.5 0.8   1  1.5    C* 1953
88- 50 A 94-11-19 10:55: 2.1 WN    3.4 0.8   1  3.4    C* 1953
88- 50 A 94-11-19 10:55: 5.5 WN    4.1 0.8   1  4.1    C* 1953
88- 50 A 94-11-19 10:55: 9.6 WN    1.3 0.8   1  1.3    C* 1953
88- 50 A 94-11-19 10:55:10.9 WN   65.4 0.8  15  4.36   C* 1953, irreg, A'A'
88- 50 A 94-11-19 10:56:16.3 WN   69.8 0.8  16  4.36   C* 1953, irreg, A'A'
88- 50 A 95-02-03  0:27:38.4 WN   76.9 0.8  23  3.35   C* 1953, irreg, A'A'
88- 50 A 95-02-05 23:45:21.9 WN  127.3 0.6  38  3.35   C* 1953, A'A'
As usual, my log shows more detail than I report here.

Since I discovered C* 1933 to be flashing in a spectacularly irregular way, a way which suggested that it might be in distress, I have been interested in trying to verify the obvious theory. Which is: These large, valuable payloads use propellant to stabilize during their useful life. At some point, possibly terminating their useful life, they suffer catastrophic failure of attitude control, often (?) due to exhaustion of the propellant supply. They begin tumbling wildly. Consequently, they flash. The flashes can include full solar panel reflection. Thereafter, eddy currents within the object and the Earth's magnetic field slow the rotation and eventually end virtually all the flashing, except for, (is this the right term?), synodic effect.

For a list of satellites in the C* 1933 family, see Flash 88, December 1994. Quite a few of them have been seen to flash, e.g., from my own log, 1703, 1892, 2058, 2151, 2242. I have observed many dozens of unreported passages, most of them S for minutes on end, where S excepts smooth variation due to range and phase, and apparent seeing effects.

I'm most interested in receiving observations of these, including radio monitoring to confirm operational intervals. BDP was kind enough to provide the PPAS observations (in overwhelming quantity. I keep trying).

According to BDP, you can see full solar panel reflection from an operating satellite. I question this based on efficiency (it has to be pointed at the Sun) and experience (I can't think of many examples of really bright flashers). Some flashers I've seen are:

10820  78 42A  DMSP F3
11060  78 96A  Tiros N
19460  88 78A  USA 32
21949  92 23A  USA 81
23099  94 27A  SROSS-C2
Ryan Rudnicki, thanks for triggering this summary by your observation and report. In reporting observations, you act more responsibly than I.

Bart De Pontieu, Garching, Germany

I observed 79- 30 B on January 28 with a flash period of 4.53 seconds (+- 0.05). There was quite a lot of scatter on the measured periods (I timed 43 flashes). This satellite has a history of accelerations. It looks like it accelerated between November 1994 and now, maybe DC's measurement of 4.42 on November 8, 1995 was the first after the acceleration?

Leo Wikholm, Helsinki, Finland

Eero Rantalaiho, Virkkala, Finland

I saw the flying triangle NOSS 2-1 on January 4. The formation was at magnitude +3 at it moved from Cygni to Cepheus.

Lacrosse 2 was visible on January 15 evening. I saw the satellite at magnitude +2 near Sagittarius.

Possible UARS on January 31 at 17.39 UT. The satellite was at mag +4 and the path was something like RA 2h 13min, Decl 25d 18' to RA 4h 22min, Decl 24d 25'. After this it went into Earth's shadow. Coordinates of Virkkala are +60d 12'N +24d 0'E

Ilkka Yrjola and Marko Toivonen, Kuusankoski, Finland

Flash! We observed quadrantids on January 3 at 18.10. Suddenly we saw a bright flash at magnitude -2 which was visible about 15 seconds at location RA 12h 50' Decl +49d. Our coordinates for Kuusankoski were +60.9N +26.6E.

Timo Kinnunen, Espoo, Finland

I saw a very slow satellite moving only one degree per minute. The date was Nov 19, 1994 and the time was 1:38 UT. The satellite was at location RA 2h 14min 30s, Decl +57d 17' and it moved to the Northwest. Coordinates for Espoo are +60d 14' 29"N and +24d 48' 58"E.

compiled by BDP

Next: Determining the orientation Up: Flash 90 Previous: Satorial