This is a tough event. Only 5 degrees from the 55% waxing moon. It's high, at 66 degrees, no problem for our standard straight-through configuration, and hopefully minimizing any aerosol or cloud moonlight scattering. Long integration won't be possible with the moonlight. Hopefully 2x or 4x will pick up the star, since also the duration is only 0.5s. The rank is good, so odds of a positive are good near the centerline. The centerline goes near Canham Rd in Scotts Valley, near St. Clares on Mtn View, just north of Castelegno's, a bit south of Olive Springs Quarry, and just a 1/4 mile from Glaum Egg Ranch in Day Valley. Very convenient for Jordan. She said she'd try it, if she got home from an outing in time.
Alt=66, Az=262 in Auriga
Karl will try from Olive Springs. I will try from Mtn School or nearby, and we'll meet up afterwards. Jordan will try from home. Kirk from Quail Hollow.
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I set up at 3182 Old SJ Rd, in a wide spot on the east side of the road, near a big iron gated residence. The cirrus of the day pretty much had disappeared, and my fear over the mere 5 degree separation from the 55% moon was unnecessary. The star was quite easy to follow at 4x and gave a clear 0.5s event. Met with Karl and Carla afterwards at Castelegno's and reviewed our tapes.
Either a jet contrail or a tracking glitch caused a few seconds of loss for all stars tracked early on. This part of the light curve was trimmed out before processing in PyOTE. I'd worried that the moon only 5 degrees away would make this very tough, but the sky was clean enough to make this not a problem at 4x setting. I got a solid looking square wave 0.45s occultation.
magDrop report: percentDrop: 98.4 magDrop: 4.504 too much noise; cannot calculate error bars
DNR: 5.72
D time: [04:13:30.7859]
D: 0.6800 containment intervals: {+/- 0.0131} seconds
D: 0.9500 containment intervals: {+/- 0.0317} seconds
D: 0.9973 containment intervals: {+/- 0.0621} seconds
R time: [04:13:31.2393]
R: 0.6800 containment intervals: {+/- 0.0131} seconds
R: 0.9500 containment intervals: {+/- 0.0317} seconds
R: 0.9973 containment intervals: {+/- 0.0621} seconds
Duration (R - D): 0.4534 seconds
Duration: 0.6800 containment intervals: {+/- 0.0196} seconds
Duration: 0.9500 containment intervals: {+/- 0.0433} seconds
Duration: 0.9973 containment intervals: {+/- 0.0786} seconds
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Karl and I check his and my recordings, at Castelegno's
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I got a noisy 0.2669 positive for 2000 EU94, 2x at the Sky Park parking lot March 25. There were dips in the tracking/reference stars, not sure of the cause, there was a slight wind during the recording but there wasn't strong camera shake. There were thin clouds on the horizon, but it looked clear in the target area, however there could have been unseen clouds. Or it might have been poor seeing, like heat currents from the parking lot. But the variations were smoothed in PyOTE against a tracking star and it found an event near predicted time. The duration of 0.2669 is significantly shorter than Karl's at 0.4004, but I was closer to the path edge.
PyOTE NIE sigma distance = 8.1.
magDrop report: percentDrop: 98.4 magDrop: 4.459 too much noise; cannot calculate error bars
DNR: 2.63
D time: [04:13:30.4294]
D: 0.6800 containment intervals: {+/- 0.0112} seconds
D: 0.9500 containment intervals: {+/- 0.0315} seconds
D: 0.9973 containment intervals: {+/- 0.0784} seconds
R time: [04:13:30.6963]
R: 0.6800 containment intervals: {+/- 0.0112} seconds
R: 0.9500 containment intervals: {+/- 0.0315} seconds
R: 0.9973 containment intervals: {+/- 0.0784} seconds
Duration (R - D): 0.2669 seconds
Duration: 0.6800 containment intervals: {+/- 0.0168} seconds
Duration: 0.9500 containment intervals: {+/- 0.0404} seconds
Duration: 0.9973 containment intervals: {+/- 0.0867} seconds
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Mar 25 9:13:31 (45668) 2000 EU94 from near beginning of Olive Springs Road (Site Lng: -121° 56' 13", Lat: +37° 02' 39”), Alt: 85 m -or (-121 56 17; +37 02 40 70m )? used 2X Clear, fairly steady, near to (~5 deg) 1st quarter moon, no wind, looked like very short blink, but not easy to see. Reported to OW Cloud: “report to follow"
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