This is a good rank event by a bright enough star, lasting long enough 0.7s, and high enough (51 deg Az=224) to be quite do-able, if the path will just behave as it is supposed to. This is late enough that Kirk and I should be ~done with our Bristlecone Milky Way imaging, or at least take a break. I will plan to leave Kirk at the grove, and I will take the van back down a few miles to get a path a little closer to the centerline. Kirk, I, Karl are all inside the predicted path. Karl is nearer the southern limit, Kirk and I nearer the northern limitl
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Kirk and I made it to the Patriarch Grove of Bristlecones and got our bristlecone research successfully accomplished, and got almost all the way up White Mtn earlier in the day. We had clear skies tonight, unlike spotty clouds the night before. I got in a bit of a nap, which really helped, before trying this event. Kirk set up at the parking lot of the Patriarch Grove
I took the van down to to the end of the access road, to the paved portion of the White Mtn road, and then another 0.8 miles further down hill on that road till I found a good turnout to set up. The goal was to set up decently spaced across this asteroid shadow. I hoped Karl would be above any fog and get the southern area of the shadow. Kirk would be near the northern shadow limit, and I'd be closer to the centerline.
I got set up, turned on my OccBox, and... nothing showed on the monitor. Luckily I didn't panic, even though time was now very short. I figured it may be as simple as a 12v male/female plug connection had jarred loose, given the 15 miles of washboard'ing already accomplished on this box. I snugged everything down. Still no power. Snugged again, and this time I did get power to the monitor and VTI. Next problem was focusing. The event was short enough I wanted and expected I'd be able to do this at 2x, given we're over 11,000 ft up, and the altitude of the target was over 50 degrees. But it took 4x to see it very faintly. I stuck with 4x but the focus wasn't perfect. After the event passed and I got enough time afterward to feel comfortable, I adjusted focus one more time and now I could see the target star more consistently. So, it'll just take a bigger circle on the sky to get the light.
Later in the day, we had internet connection on Kirk's iPhone 13, and got a confirmation of a 0.7s positive from near the centerline, so I am confident I should have a good positive.
long: 118 12 19.87
Lat: 37 30 27.31"
Elev: 10,746 ft
Reductions:
I trimmed out the ending noise from when I tried to refocus, and then did the usual calibration with star Ref1. No time offset improved the flatness. I questioned the need for a calibration star, as the flatness inched better monotonically with rising smoothing interval. I found I could get a better False Positive test by no using a reference star at all, and that is what is reported below.
There's a noticable rise in light for the middle two integrations of the obvious drop at the predicted event time. Likely this is just noise around the new lower level. The 'no-star' level is as shown, and because of the very dark sky at 10,700 ft elevation, the sky pixel brightness distribution is clearly clipped and so the "sky" level ends up being net positive, just a bit below the occulted level. The % drop shown below does not take account of this clipped sky pixel distribution, and the estimated brightness loss is more like 95% or higher.
magDrop report: percentDrop: 83.4 magDrop: 1.953 +/- 0.909 (0.95 ci)
DNR: 1.91
D time: [08:44:39.2861]
D: 0.6800 containment intervals: {+/- 0.0386} seconds
D: 0.9500 containment intervals: {+/- 0.1365} seconds
D: 0.9973 containment intervals: {+/- 0.3273} seconds
R time: [08:44:40.1661]
R: 0.6800 containment intervals: {+/- 0.0386} seconds
R: 0.9500 containment intervals: {+/- 0.1365} seconds
R: 0.9973 containment intervals: {+/- 0.3273} seconds
Duration (R - D): 0.8800 seconds
Duration: 0.6800 containment intervals: {+/- 0.0623} seconds
Duration: 0.9500 containment intervals: {+/- 0.1697} seconds
Duration: 0.9973 containment intervals: {+/- 0.3704} seconds
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Kirk set up on the south side of the circle at the Patriarch Grove and didn't see the target well enough at 4x and so chose 8x for the recording. His impression while watching live, was that he had a positive.
Got a clear 0.6635 sec event for 2002 CB59 at Patriarch Grove, 8x. Widely passed the false positive test.
I don't see significant bumps in the bottom of the event.
I tried it both with and without smoothing on another star, results were very similar, DNR was the same,
but containment intervals were slightly better (millisecond or tenths of a millisecond) smoothed to another star (below).
magDrop report: percentDrop: 87.3 magDrop: 2.238 +/- 0.469 (0.95 ci)
DNR: 3.49
D time: [08:44:39.4826]
D: 0.6800 containment intervals: {+/- 0.0235} seconds
D: 0.9500 containment intervals: {+/- 0.0622} seconds
D: 0.9973 containment intervals: {+/- 0.1196} seconds
R time: [08:44:40.1461]
R: 0.6800 containment intervals: {+/- 0.0235} seconds
R: 0.9500 containment intervals: {+/- 0.0622} seconds
R: 0.9973 containment intervals: {+/- 0.1196} seconds
Duration (R - D): 0.6635 seconds
Duration: 0.6800 containment intervals: {+/- 0.0350} seconds
Duration: 0.9500 containment intervals: {+/- 0.0796} seconds
Duration: 0.9973 containment intervals: {+/- 0.1421} seconds
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Karl was ready to set up at home, but fog came up the canyon and covered his elevation. No data.