The Germania Occultation

Sept 12, 2017

This bright event was the best asteroid occultation for Santa Cruz of 2017, and was the focus for the 2017 IOTA Annual Meeting in Carson City. A 9.0 star well up in a dark moonless sky. Alas, the weather turned out to be baad, both in Nevada, and in California. But not so bad that I gave up on it. It looked promising, actually, at 10pm when I took a last look outside and saw ~60% clear skies. I drove up to the Upper Meadow at UCSC ( I was at track -39.7 km.) because the parking area below my Apt was jammed and had too many lights going. Had trouble with the 8" scope, it seems to have some bad star data. I tried to do a 2-star alignment using Hamal (failed, went vertical and jammed), tried Altair (failed), tried Enif (failed). Tried Deneb (success) and then Nunki (success). Got on target, clouds now at 50% of sky, but mostly leaving the tripod of Aquarius alone. But then, ~30 sec before the D, a large cloud covered the target, and didn't clear away until after the event was over by ~5 seconds. "Nasoned"!

Center of the occultation was predicted to be 11:15:18pm. However, Steve Messner got two chords near the southern limit and both showed the occultation was 5 sec early and also about 8 km south of predicted. So that would make central occultation at 11:15:13pm, and for an 18 sec max duration or 9 sec after center, that means the R should have been close to 11:15:22pm.

The LiMovie screen capture below was after doing a light curve with no tracking and large enough circles that it would include where it came out of the cloud. It looks solidly like the actual exit from the cloud came several seconds after the expected R, based on Messner's 5s early timings. Based on this, I can't claim to have any data to report.