(Plot produced by my Synodic program attached to reply to Ed Cannon) > Recently when I've had chances to time SPOT 3 (93-61A, 22823), > I've always come up with a fractional cycle in the middle of > my timings. For example, last night while Mike was observing > the eccentric flashing UNID and it was too faint for > binoculars, I looked for SPOT 3 and saw it do a few one-power ... > > From longer observations on other nights, I'm fairly sure that > the fundamental flash period is about 21 seconds, but I can't > quite figure out how to analyze the above timings, specifically > numbers 2 through 6, which are similar to "non-fitting" timings > on other evenings. It seems that either 2 and 3 or 5 and 6 must > constitute a fraction of about 3/4 of the fundamental period. > If so, would that be a "phase shift"? > Definitely - I have seen and analyzed several reports like this, and saw some passes myself at about 40 deg W-NW, before Nordic twilight overtook the orbit. From your few points, I get 21.15 s period as the best fit (21.10 from 3,6,7 - shift -5.5 s; 21.19 from 2,5 - shift +1.9 s). This is similar to other observations. I am not at all convinced that a 1/4 cycle should be expected - it depends on the orientation of the two (three) reflecting surfaces AND the rotational axis - which are probably not ALL at right angles. However, if I can find the time, and all reported BRIGHT flash observations, I should be able to determine the surfaces, and the rotational axis. -- bjorn.gimle@tietotech.se (office) -- -- b_gimle@algonet.se (home) http://www.algonet.se/~b_gimle -- -- COSPAR 5919, MALMA, 59.2615 N, 18.6206 E, 33 m -- -- COSPAR 5918, HAMMARBY, 59.2985 N, 18.1045 E, 44 m -- -- SeeSat-L / Visual Satellite Observer Home Page found at -- -- http://www2.satellite.eu.org/satintro.html -- ----------------------------------------------------------------- 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 : Thu May 25 2000 - 00:33:27 PDT