This is a vertical path which manages to cross most of the NorCal occ observers and should have a good turnout if clear. I plan to try from home, neart the eastern limit. The rank is poor, however.
Alt=50, Az=238 so may need to observe from the end of the driveway. Along the "neck of Pegasus, near Markab (lower left corner of Great Square)
|
|
Clear skies and good conditions, high in the sky. But a poor rank...
I observed from about 60ft south of my carport, under my neighbor's deck (next to the opposum rummaging in the bushes next to me!). While recording at 4x and gamma=0.85, it looked like a miss, but PyOTE did find an event, of low FP pass, and 4 seconds early. For this low rank event, it's certainly possible, but without a confirming occultation, it may be classified as "UNK". Unfortuntely, in handling the camcorder, I must have accidentally flipped a lever from "tape" to "camera", and when I started the recording it said "No Card", which confused me, since I had flipped the power switch to the correct 'tape' position. I tried several times on the power switch, and as time was now very short, I instead took video off the monitor with the Canon Powershot. That worked, but the S/N is not as good as the initial tape. A full disappearance for .7 or .8 seconds would be quite clear, I felt. A shorter event, and with sky counts not at zero, would be tougher to judge its significance. That's, however, what I have. The only reasonable candidate for an event was early, and detectable, but only passed the false positive test at about 1.4-sigma. Hardly convincing, but also not a convincing miss either.
3.5 seconds before predicted time, which is 4 diameters early, Unlikely but possible given the low rank of this event. Will be filed with IOTA report of "unsure".
magDrop report: percentDrop: 47.8 magDrop: 0.706 +/- 0.037 (0.95 ci)
DNR: 1.98
D time: [06:08:58.4124]
D: 0.6800 containment intervals: {+/- 0.0205} seconds
D: 0.9500 containment intervals: {+/- 0.0536} seconds
D: 0.9973 containment intervals: {+/- 0.1250} seconds
R time: [06:08:58.8638]
R: 0.6800 containment intervals: {+/- 0.0205} seconds
R: 0.9500 containment intervals: {+/- 0.0536} seconds
R: 0.9973 containment intervals: {+/- 0.1250} seconds
Duration (R - D): 0.4514 seconds
Duration: 0.6800 containment intervals: {+/- 0.0286} seconds
Duration: 0.9500 containment intervals: {+/- 0.0674} seconds
Duration: 0.9973 containment intervals: {+/- 0.1469} seconds
 |
 |
 |
I gave it the D and R interval most likely to be real that was close to the event time, and it did detect it, but at low significance. |
 |
 |
No known successful recordings to the west of me, to confirm or rule out this low-sig event, unfortunately. |
My recording at home of 1998 VF46, 4x, I don't see an event; neither at the predicted time, nor at your proposed time. I did a 12-stack of nested static apertures, they were pretty much the same and didn't show an event over the noise. I did a size 3.2 static aperture, smoothing on a tracking star, no apparent event. The pyote detectability test on my data said"An event of duration 0.150 seconds with magDrop: 5.5 is likely detectable." Max predicted was 0.83 sec. so according to that, if there was an event I'd have likely detected it. I did have one bad timestamp at 6:08:45.7484.
 |
 |
 |
|
Drove to Garth's to get on the edge of the path, but lost track of time and didn't get set up in time. No data.
Found a better than 3-sigma positive of 0.24s long, but only 30% depth. But he was on the far side of Yanzhe and Ted's chords, not on my side of the track. If my noisy event was a positive, it was more than 50% drop, making Kent's 30% drop then possible as a binary. His data must be much calmer and better S/N than mine I don't think I could detect a 30% drop in my data, not for only 0.24s. So, if they're both real, it may be a binary star and Kirk threaded the "Pillars of Hercules" between the two stars. But the double star flag was not indicated on the OWc page, nor on the OW desktop page.
Yanzhe Liu had a station between Kirk and Kent and could shed light on what happened, but I have not seen a result from his attempt yet, or if so, I missed seeing it.
