This good event is visible in a high rank event that covers all of Santa Cruz County, down to Moss Landing, and north to San Francisco and Hayward. It's a long event, 3.7s and so will allow some ability to integrate longer to get a better positive detection. Alt=32, Az=161.7, at 11:00pm, rising to 34 deg as it goes east to Az=167 at event time. Liu and perhaps others in the South Bay are on board, so with all of us, we should get good astrometry and shape for this asteroid. Also be sure to go a full minute and a half before and after the event, to search for moons. Long duration events are much better for searching for asteroid moons.
Fog, despite predictions of clear skies down below, actually came up quite high. I had to scramble to get above it, and with just 1/2 hr left, arrived at the Sunlit Ln sight where Kirk was expected to be, and this was about 150 ft of elevation above the fog. I did not have in mind a site within driving distance that would be better. I also thought that one of the values of doubling up could be confirmation if we saw a moonlet. And so, I set up about 70 yards east of Kirk, just east of the driveway to the home there.
We had clear skies and compared to the previous nights trip here and lock on to the target, the seeing was MUCH better, although still not perfect. No high clouds, and we did not see any trace of fog.
I integrated at 8x. My light curve looks a bit ratty, but the 2.72s event is clear and obvious. I used a 4px circular static aperture for the target and ref1 comparison star. The sky was clipped, and the bottom of the light curve is consistent with the drop expected of 1.6 to 1.9 magnitudes.
magDrop report: percentDrop: 67.6 magDrop: 1.224 +/- 0.350 (0.95 ci)
DNR: 2.28
D time: [06:22:52.2243]
D: 0.6800 containment intervals: {+/- 0.0759} seconds
D: 0.9500 containment intervals: {+/- 0.2517} seconds
D: 0.9973 containment intervals: {+/- 0.6387} seconds
R time: [06:22:54.9443]
R: 0.6800 containment intervals: {+/- 0.0759} seconds
R: 0.9500 containment intervals: {+/- 0.2517} seconds
R: 0.9973 containment intervals: {+/- 0.6387} seconds
Duration (R - D): 2.7200 seconds
Duration: 0.6800 containment intervals: {+/- 0.1204} seconds
Duration: 0.9500 containment intervals: {+/- 0.3300} seconds
Duration: 0.9973 containment intervals: {+/- 0.7349} seconds
Observed from just ~50 yards further down Sunlit lane from me, at the end of the airstrip. Used 16x integration.
magDrop report: percentDrop: 62.5 magDrop: 1.064 +/- 0.275 (0.95 ci)
DNR: 3.34
D time: [06:22:52.1401]
D: 0.6800 containment intervals: {+/- 0.0836} seconds
D: 0.9500 containment intervals: {+/- 0.2199} seconds
D: 0.9973 containment intervals: {+/- 0.5294} seconds
R time: [06:22:55.0763]
R: 0.6800 containment intervals: {+/- 0.0836} seconds
R: 0.9500 containment intervals: {+/- 0.2199} seconds
R: 0.9973 containment intervals: {+/- 0.5294} seconds
Duration (R - D): 2.9362 seconds
Duration: 0.6800 containment intervals: {+/- 0.1292} seconds
Duration: 0.9500 containment intervals: {+/- 0.3055} seconds
Duration: 0.9973 containment intervals: {+/- 0.6538} second