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Description of observations

I report here for PPAS(beginning):

Walter I. Nissen, Jr., CDP,, 55 Barrett RD #808, 
Berea, OH 44017-1657, USA, 216-243-4980, -81d 51.823', 41d 22.413', 256m, 
81- 59 A 96-05-29  2:22:38.6 WN   14.9  .5   4  3.7   NOAA 7, F'Ff...fF'F 
                                                      bright dbl F, add'l sm

The bright, very rapid, untimably rapid, double flashes from NOAA 7 were quite striking and, so far as I can remember, unique in my experience. There were also a number of secondary maxima, which may have been irregular in spacing. "untimably" may not yet be a word; I use it to mean they were too rapid to be timed separately.

I previously asked this question (on SeeSat-L) and got no response: Has anyone seen bright, very rapid, double flashes from NOAA 7? Or other objects?

After seeing the remarkable, extremely bright, rapid, double flashes that I reported for 960529, I have been trying to keep watch on NOAA 7 thru the occasional breaks in the clouds here. For some weeks I was unable to see those double Fs again. Mostly I have seen a very irregular pattern which displays repeated bright Fs and many secondary maxima which vary in brightness and also perhaps in time. But 960624 I caught the object early in its rise and dedicated myself to timing only the bright Fs. Consequently I was able to follow the object for a considerably long period and time all (but one of) the bright Fs over the entire period. I also observed the rapid double Fs for a short while. Again, they were so rapid I was unable to time the second of each pair in the double Fs. In some ways this object is now quite reminiscent of the behavior of the spectacular, irregular flashers C* 1933 = 88- 20 A = 18958, C* 1953 = 88- 50 A = 19210, SROSS-C2 = 94- 27 A = 23099, and DMSP F3 = 78- 42 A = 10820 when they were at their most irregular. Upon analysis of the recorded timings, the Fs are seen to come very regularly.

I am not sure everyone would reduce the data shown below in the same way, but it appears that a case can be made from this data that this object is spinning up (the vagaries of the English language are such that this means the same as, and confirms, the comment in the March-April Satorama "is probably going down a bit"). Most of the timings are of bright sharp Fs, but not all.

Does anyone think there is evidence for a slight asymmetry within a 7.4s period?

But besides any acceleration or any asymmetry, the appearance may vary from day to day or week to week or even within the same pass. On 960529 the bright Fs were separated by only perhaps 1/6 of a second and were too rapid to be timed separately. On 960606 the bright Fs were about .8s apart or a little more. On 960611, they were mostly about 3.7 seconds apart. On 960624 a whole variety of behavior was seen at different times.

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