The Myrrha Occultation - Jan 10/11, 2014

This was a good, high-rank event, with a bright reddish star (V=11.0, R=10.4) in Gemini, at high altitude. "Plan A" was to drive to Pt. Reyes with the 10" and video gear, and go for this event, then do some trail running and kayaking, oyster enjoying, and quiet time at the hostel getting some work done on my laptop. I was really looking forward to the trip.... but the observatory was broken into, and all of our video-timing gear was stolen, as well as the cabling, power supplies, eyepieces etc for the 10" scope, and many $thousands of more too depressing to go into here.

Cabrillo was at track 61km south, with odds of success of 61%. Pretty good! Predicted central occultation was 7:37:41 UT

So, Plan B was to instead get the event from Cabrillo Observatory using the 12" dome scope, which is permanently mounted and unlikely to be stolen w/o a great deal of work. However, I still had no video gear, so this would be a low time resolution star trail. I got on the target without too much trouble. I tested which direction the star would drift (it would drift "up"), and then started a 50 second exposure at high resolution, with my digital watch at 11:37:19.15, which is about 5 seconds ahead of the true time. The NIST live clock seemed to bog my computer to a crawl and wouldn't display the time at all. Something's screwy there, but that's another hassle to settle later.

Cabrillo was just inside the southern limit, by a few km. The northern limit was just a few km south of Ted Swift, so between us we should be able to nail this pretty well. I had a clear miss. Ted's not sure but thought he had a miss too, which would mean the asteroid must've threaded the needle very precisely, or else was much smaller than predicted, or else was WAY off from the prediction, which isn't likely given the high rank.

The 50 second exposure during the predicted occultation time of 7:37:43UT. No dip, let along a full 2.5 mag occultation. Definite miss.

Here's the star and v=13.5 asteroid separated, about a half hour later


Derek kindly sent along a screen shot from his .avi of the Myrrha event, showing an enviable FOV.

Derek Breit's Myrrha, image from his .avi file. 12" with f/6.3 + Owl + adapter ring + Watech 1/2" chip. Looks like 14' x 20' wide.