This is a wide path event, Amazone is a 64km wide asteroid. This one will be good for searching for moons, if we have crystal clean skies as we might indeed have, to minimize nearby moon glow. So, don't integrate more than needed. 4x I'm hoping will be good. The star will be 0.7 magnitudes dimmer in V than it would be if it were at a typical good altitude of 60 degrees. So the W=11.7 star will look more like 12.4, and in a bright sky under a . That might take 8x, but I hope 4x will work. That's plenty of time resolution for a 5s long event. Yanzhe over the hill is trying it too.
Alt=16, Az=193
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Fog came in and made a bit of a chaotic situation. I decided early that this event was do-able in a clean sky, and a clean sky would require being comfortably above the fog and not by just a little. So I told Kirk I'd be going to Sunlit Lane. Kirk went to "the Berm" which is much lower. As I was driving up, I could see the fog was already at the level the "berm" and did not see Kirk there. I did see him in his Prius at the fire station on Felton -Empire Rd. He saw me going up the BD airport and so he went back down to the Berm, which was now clearing above the fog. We both got good recordings. Karl's attempt may have been fogged out; not sure yet.
I was at Sunlite Lane, at the end of the airstrip. The 99.3% full moon brightened the sky enough that the 11.7 star was only barely visible above the sky on the monitor, but only at 4x. At 8x it was a white-out. The dew shield helped, but still some direct moonligh was entering the corrector plate. I could have used a black cloth to drape over the dew sheild. Instead, best I could do was to use one of my headband lights with a black elastic piece which I draped a bit over the top of the dew shield. As event time got closer, the target star got a bit easier to see, and I could verify a ~4s occutation at the proper time.
I found out later, that I accidentally taped over this recording. Gone. So I only have the visual confirmation of a ~4s occultation watching it on the monitor. That's still useful, since Kirk got a positive also, and we were the only two.
Got a 4.8 sec event for Amazone last Friday morning, across from the fire station at Felton Empire crossing.
It was hard to see the target at 4x so I used 8x but turned down the gain, otherwise the moonlight made it a white-out.
magDrop report: percentDrop: 75.8 magDrop: 1.542 +/- 0.325 (0.95 ci)
DNR: 2.54
D time: [07:57:07.9837]
D: 0.6800 containment intervals: {+/- 0.0557} seconds
D: 0.9500 containment intervals: {+/- 0.1700} seconds
D: 0.9973 containment intervals: {+/- 0.4378} seconds
R time: [07:57:12.7884]
R: 0.6800 containment intervals: {+/- 0.0557} seconds
R: 0.9500 containment intervals: {+/- 0.1700} seconds
R: 0.9973 containment intervals: {+/- 0.4378} seconds
Duration (R - D): 4.8047 seconds
Duration: 0.6800 containment intervals: {+/- 0.0872} seconds
Duration: 0.9500 containment intervals: {+/- 0.2235} seconds
Duration: 0.9973 containment intervals: {+/- 0.4913} seconds