The Occultation by Feronia

Mar 5, 2015

This was the brightest decent rank occultation in some time, but the northern limit was just south of Cabrillo Observatory. The odds of occultation was given as 35%; worth a go. For most of my occultation history, it's been the 10" Meade as the workhorse. But I have been seeing flakey electronics in the 10" Meade for the past few months, especially lately. It'll just stop responding to the hand paddle. And, it even did a declination walk-about on Tuesday, requiring a plug pull after conking on the photometer. The only recovery is a time-consuming 2-star re-alignment and then hoping it doesn't happen again. Also, it's been dewing up from the INside of the corrector plate, which is harder to remove with a dew gun, and impossible from the field. So, I'm hesitant to use it for going mobile, especially for long miles. On the other hand, the PC165DNR has plenty of range on the 80mm Orion ShortTube refractor finderscope on the 12" in the dome, and it's so very nice and comfy to be able to set up in the warm room, plug in a few wires, and get stars down to 12th magnitude on the camcorder. The compromise is the time resolution is only 1/3 second, but I can tune that. That'll be my next project, is to settle on a procedure for easily changing the integration time while not dismounting the videocamera.

The event was at 5:22AM on Thursday. I arrived at the observatory at 10:30pm and spent the next 2 hours making a new mount model for the G11 Losmandy mount. It's not perfect enough yet, given the smaller FOV now on the Orion scope (only ~2x the CCD frame). But it is good enough until I get more time to add more stars. I got in about 2 dozen stars before getting a few hours sleep.

I woke up 40 minutes before the event, and final connections and pointing went fine, and although the initial pointing wasn't perfect, I got on the target in plenty of time, and got a clean recording.... of a miss. 15 minutes or so before the event, I got a 22 second CCD image of the dim asteroid just above the bright 8.7 magnitude target star, at left.