The Occultation of a W=14.1 Star for 1.4s by Asteroid (2139) Makharadze

Sun eve Dec 7, 2025 at 9:17:16pm

OWc page

 

This is a faint event, difficult in a 8SE, but lasts 1.4s which should make it do-able. More to my goals, it's high in the sky and well placed to try at Cabrillo Observatory. My goal is to find the most efficient process to hook up my OccBox and gear to the 12" f/6.3 rather than the 8SE. Jordan will be along to help.

Alt=36, Az=87 in the foot of Gemini, in the Jellyfish Nebula

These charts are strictly for the 12" as it is straight through. Boxes and circles are for 8SE size, for lack of time. Actual size on 12" will be 1/3 as large as the box view on Watec chip.

     

 

Results:

Richard Nolthenius

I got a successful recording of the 1999WF event, then moved the occ box, computer, and other gear to the 12" Dome scope and tried to get the Makharadze event on the 12" scope, which would be the first asteroid occ gotten from this scope. It was harder than expected to get the telescope on-target. I first had to get a recognizable bright star in the eastern side of the sky that I could calibrate on first in Gemini software, and then synch C2A on the same star. Then sent to the RA/Dec Jnow of the target, and was able to recognize the star pattern. I got the CCD ST2000st2k CCD camera off the 12" scope and mounted the Watec. Now at f/6.3 instead of f/3.3 on an 8", so the field of view was much smaller. But the real problem was that I could not achieve focus. Despite being in Gemini with lots of stars, I got nothing to focus. Then I swapped in a 0.5x reducer onto the nosepiece of the Watec and tried again. Still, could not get focus. However, I distinctly recall that I did indeed get the Watec to focus on the 12". So, there's more work needing to be done to clarify this.

Bottom line for me - got no data. I did spend a lot of time after the missed occultation trying to learn more, which ended up compromising my ability to get the 3rd occ of the night, WeisseRose, which I tried to get from home right after arriving home.

Kirk Bender

From home, 16x, noisy but looks like I got a positive, on the order of a second.