This is a bright and very long event, and the location is only about 10 degrees below/right of the 2001 YE79 event 14 minutes earliier. Euphrosyne has a moon, but it's separate prediction path is unknown for this event tonight. In the unlikely event that we get a central occultation by the moonlet, its occultation will last only 0.41s. The target star is W=12.7.
The duration is long at 30s, but the depth of the occultation will be shallow, at only 0.7 magnitude in R. The SDSS star chart shows another UCAC4 dimmer star just ~13 arcsec away, which will also complicate the reductions of our observations. The 100% full moon is only 42 degrees away, farther east in eastern Scorpius.
The centerline is very close to MIRA, and the northern limit is through Sacramento and just north of Davis, where Ted Swift will try it. This is the 7th largest asteroid, with a wide path. It's been tracked since 1854 and so the orbit is likely quite accurate. The asteroid is also believed to be extremely close to spherical in shape. Seeing the moonlet would be very lucky, and difficult.
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Many signed up for this event, with its wide path - but troubles bit everyone - except me.
I got a clear and long drop in brightness visually as I watched on the monitor. I disconnected the monitor. I set up at Sunlit lane, NE end of the gravel area. However, the depth by eye looked rather shallow, maybe 0.4 magnitude? Not the 0.7 magnitude expected. I have not reduced it yet. I'll describe that below. I used 4x setting. Recorded on PAL camcorder.
start: 6:40:09 UT
End 6:47:46 UT
magDrop report: percentDrop: 36.4 magDrop: 0.491 +/- 0.024 (0.95 ci)
DNR: 2.24
D time: [06:43:09.2814]
D: 0.6800 containment intervals: {+/- 0.0418} seconds
D: 0.9500 containment intervals: {+/- 0.1793} seconds
D: 0.9973 containment intervals: {+/- 0.5037} seconds
R time: [06:43:35.0013]
R: 0.6800 containment intervals: {+/- 0.0418} seconds
R: 0.9500 containment intervals: {+/- 0.1793} seconds
R: 0.9973 containment intervals: {+/- 0.5037} seconds
Duration (R - D): 25.7199 seconds
Duration: 0.6800 containment intervals: {+/- 0.0719} seconds
Duration: 0.9500 containment intervals: {+/- 0.2604} seconds
Duration: 0.9973 containment intervals: {+/- 0.6100} seconds
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