This is a very easy event, and good rank. It's only drawbacks are low altitude of only 14 degrees in the east, and we have to go to Moss Landing for it. But horizons are good in that area and I plan to try it from the road across from the gas station just north of the slough there - a spot I've used before and is quiet and on a low hill.
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Kirk carpooled with me, heading to Moss Landing - then we hit fog and realized it was worse as we went south, and I turned around to head back north and at least be able to get data. We ended up in Pajaro, at the northern limit and just barely got out of the clouds enough to get our data. The time loss meant we had to set up at the same spot - a bare spot about a mile south of Pajaro. We both got recordings. My recording shows two cloud "occultations" mirrored in the comparison star's light curve. It looks like we had a miss.
I processed this in frame mode, even though I recorded in field mode, to try to damp noise and given the max duration should have been 20 fields or 10 frames. Two obvious clouds (the target was on the ragged edge of clouds during the recording), and low in the sky at 14 degrees, with a background moon, causing more noise than usual.
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No hint or significant drop indicating a positive. Looks like a miss.
After Kirk submitted his data, I re-analyzed mine. This time I did it in 'field mode'. But above, I processed in frame mode even though I integrated at 1x. A full duration event would then occupy 10 frames or 20 fields. In fact, I got only 1 field that was low, but no lower than more than a dozen other low points in the calibrated target curve. The occultation should have gone to zero, 10 magnitude drop. I still interpret my data as a miss. I think the most likely interpretation of Kirk's data is that the seeing correlation of about 0.1s produced a drop in his counts while 9 feet away, at my spot, it did not. His drop is not to zero. Seeing-correlated noise is a real danger for these very short events. Even bright 8th or 9th magnitude can produce false detections if the altitude is low and scintillation is strong. Having two sites next to each other is then valuable. Double-occupied sites too, can help confirm or refute potential satellite events.
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I've reduced my 1993 UG6 recording at 1x in Pajaro on Oct 4, getting a 0.1669s event. There is a conspicuous dip of nine points about a second after the predicted time (3:26:18).
There was a lot of undulation in the light curve due to approaching clouds, so I trimmed it in pyote. Fortunately the curve was more flat relative to the rest of curve around the predicted time, though noisy. There was only one star other than the target for tracking, and it was dimmer than the target. Fourier finder in pymovie failed, so I used finder via star align. I tried several size apertures in pymovie, and size 4 got the best results. In finding an event without block integration, pyote gave correlation warnings and found various events early or late with low NIE results, so I block integrated the curve even though I recorded at 1x, it automatically chose block size 2. It did find the suspected dip, with NIE sigma of 3.9. I tried smoothing against the tracking star, trimmed and untrimmed, but no smoothing with trimming gave better NIE sigma results. The mag drop from the solution is smaller than predicted, but without block integration there is a point in the dip close to zero. Since we both recorded from the same location, you may be able to confirm my results. We were close the north edge of the path, but were within the north path limit so a positive should be possible.
magDrop report: percentDrop: 64.9 magDrop: 1.137 +/- 0.131 (0.95 ci)
DNR: 2.00
D time: [03:26:19.2282]
D: 0.6800 containment intervals: {+/- 0.0093} seconds
D: 0.9500 containment intervals: {+/- 0.0272} seconds
D: 0.9973 containment intervals: {+/- 0.0815} seconds
R time: [03:26:19.3951]
R: 0.6800 containment intervals: {+/- 0.0093} seconds
R: 0.9500 containment intervals: {+/- 0.0272} seconds
R: 0.9973 containment intervals: {+/- 0.0815} seconds
Duration (R - D): 0.1669 seconds
Duration: 0.6800 containment intervals: {+/- 0.0137} seconds
Duration: 0.9500 containment intervals: {+/- 0.0340} seconds
Duration: 0.9973 containment intervals: {+/- 0.0823} seconds
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RN: My interpretation of KB's light curve; at 14 degrees altitude there was significant scintillation and the typical correlation time for seeing variance is about 0.1 second. I believe that we were far enough apart, about 12 feet, that his seeing variations were not well correlated with mine, and he had a seeing dip while I had a seeing amplification at the same moment as his "event". His event did not go below the noise level of other dips, but was flagged as a detection because of the duration of the dip. However, if real it should have gone to zero given the 10 magnitude drop predicted. It's hard to see how I could have a strong star detection at the same time as his event if his event was real. In fact, I was actually 9 feet closer to the centerline than was KB.
I will report a "miss" for my observations.