This event is faint and difficult, lasting only 0.6s, but if conditions are perfect, it should be detectable. Alt=45, Az=203 in SSW, in Monoceros. Below Procyon, left of the Belt of Orion. With luck it might be do-able from the foot of my driveway. The moon is 37 degrees away; better than the 23 degrees that haunted the Monte Rd event a night earlier and likely doomed it. The sky should be drier, darker, and the star is a bit brighter. But, the duration is only 0.6 s, with full drop in brightness.
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I observed from home, from below my lower neighbor's deck. My PyOTE light curve doesn't show any hint of an occultation. Full moon 37 deg away. No hint of wind, but the star did blur from some times well after the event predicted time. Looks like a big south shift, since I was on the centerline and Kirk was halfway to the southern limit. He got a short positive, I have a miss.
Kirk Bender
Looks like I got a positive for 2002 RH21 on Jan 12. The drop is deep and near the predicted time, but it's for only one integration. I recorded at 16x from home, target looked too noisy at 8x. The target was 36 deg. from a 97% moon. In pyote I block integrated as usual and had it find an event, but it didn't find the one point drop, instead it found another much shallower drop 25 seconds earlier, whether I used manual D/R or min/max. There is a tool for single point drops in PyOTE, the "validate a potential single point event" button. I tried it for the single point near predicted, and it gave a NIE false positive graph which had a sigma distance of 5.8 (if greater than 2 the event is unlikely due to noise). However, the single point test does not give D/R, duration times, mag drop, etc. figures. The single point is at time 9:04:09.8800. I then restarted pyote, but I did a manual block integration, of size 8 for 16x, but I offset it by 4 points, so the single point drop became two points. Then it found the expected event and gave D/R times and a NIE sigma distance of 8.1. I tried multiple static aperture sizes in pymovie but still got an only one integration drop, a size of 2.4 giving the best numbers. Stats below. A one integration drop is not so great, but if you got an event we can validate each other.
magDrop report: percentDrop: 58.6 magDrop: 0.958 +/- 0.171 (0.95 ci)
DNR: 4.01
D time: [09:04:09.7466]
D: 0.6800 containment intervals: {+/- 0.0428} seconds
D: 0.9500 containment intervals: {+/- 0.1075} seconds
D: 0.9973 containment intervals: {+/- 0.2074} seconds
R time: [09:04:10.2804]
R: 0.6800 containment intervals: {+/- 0.0428} seconds
R: 0.9500 containment intervals: {+/- 0.1075} seconds
R: 0.9973 containment intervals: {+/- 0.2074} seconds
Duration (R - D): 0.5338 seconds
Duration: 0.6800 containment intervals: {+/- 0.0605} seconds
Duration: 0.9500 containment intervals: {+/- 0.1350} seconds
Duration: 0.9973 containment intervals: {+/- 0.2402} seconds
Kirk later sent this in to IOTA
I appear to have a single-integration positive for this occultation. I recorded at x16 integration on my Watec camera and the resulting .csv from PyMovie has a deep one-integration dip near the predicted time. I did try various apertures in PyMovie but all resulted in a one-integration drop. Automatic block integration in PyOTE gives a one-point drop at 9:04:09.8800, predicted time was 9:04:08. Using the "validate a potential single point event" feature in PyOTE, gives a NIE sigma distance of 5.8. However, PyOTE does not give timings for a single point event. I then re-loaded the .csv in PyOTE and did a manual block integration, of size 8 for the x16 camera integration, but offset it by 4 points, and after block integration the drop had two adjacent points. PyOTE then found a 0.5338 sec. event (predicted max was 0.64 sec.) near the predicted time with an NIE sigma distance of 8.1 and PyOTE gave timings which I used for the attached report. Let me know what you think and if finding the timings this way is ok, otherwise how to report the timing of a one-point drop, if possible, and if you need more information. Rick Nolthenius observed the same occultation on a chord 1.5km away but believes he had a miss.