This is a high value event, lasting a good long 1.5s. The asteroid is given in OWc has having a moon. In OWd, the moon symbol (**?) has the question mark so the moonlet isn't yet confirmed by occultation, I believe. The Wiki page says the moonlet was discovered by photometry showing mutual eclipses back about 20 years ago. . The path covers most of the Santa Cruz Mtns. Bernard in Carbonera is just south of the path, but could still get the moon perhaps, and a small south shift would get him into the main path as well. Sandy would more likely want to drive north into the mountains. Karl should observe from home, and Kirk and I would set up somewhere off his chord but nearby.
Weather: As of 8pm 4.5hrs before the event, the marine layer tops definitively at 2,000 ft but the data stops at 10am earlier this morning. It was slowly rising. There is no fog at the moment, 8pm June 4, but by 12:30am I expect it will have come in. I'm planning on trying it from near Loma Prieta Pk.
The duration makes it quite do-able, but a slight challenge in that the target is only 35" from a 9.7 magnitude star, so care will be needed. Perhaps best to remove the focal reducer after getting it on-target. And keep the focus as good as possible. With luck, we might get it at 4x under clean skies above the fog. I calculated the W magnitude from Hristo Pavlov's formula. It's a little brighter than I'd thought, at 13.28. It's quite similar to the event Kirk and I tried the other night in Scorpius. For that one, I could not see the target at 4x, but it was nicely easy at 8x. Even at 8x, that's 9 points inside the occultation, and if we get the moonlet, perhaps 2 or 3??
Alt=19, Az=144 in Sagittarius, 4 degrees straight above Nunki, and 2 degrees below M22.
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Kirk, Karl and I all loaded gear into cars and tried this one, given the value in helping refine the orbit for this moon'd asteroid. I got a good recording at 8x. Kirk got a recording at 16x. Karl was probably "winded out" at his site.
Start 7:27:26 UT, End 7:31:24 UT
Observed at base of Loma Prieta Pk, on Loma Chiquita Rd just uphill from a very hard to see on GoogleEarth open gate. Slight wind but not a problem like it was for Karl and Kirk. At 8x, monitor disconnected.
PyOTE says the minimum detectable duration for a 2.0 mag drop is 1.34s, but the maximum duration was 1.5s, so this looks like an event just too hard to make any judgment. A "no observation". Star just too dim. There is no suspicious dipping at the predicted time.
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I had PyOTE try to find an event, and it said "No event fitting search criteria could be found." PyOTE detectability tool reported an event of 1.1 sec would likely be detectable, 1.47 sec was predicted max. Either a miss or too short to detect.
According to my audio notes on tape, Kirk was at the open wide south side turnout on Loma Prieta Rd, past the "eclipse hill".
Karl von Ahnen
Wind at his site was hurricane force. No observations possible. AKarl was at the super windy spot he chose on the big bend in Loma Prieta Rd