The Occultation of a 10.6 Star by (885) Ulrike

Sat eve Oct 11, 2025 at 8:22pm

OWc page

 

This is a bright, long event with good rank (which I hope we can trust). It is near the 9.2 mag Globular Cluster NGC 6440 which might be a sure-fire way to point to something you know you can ID. 9.2 mag is bright and will show up easily as a non-stellar object in our Watec field.

 

Alt=20, Az=220 in Sagittarius, 10 deg to the right of the tippy top of the Teapot. It's also about 15 degrees upper left of Comet SWAN

   

 

Results:

Kirk and Bernard carpooled with me in the van. We first went to the Fremont Peak StarBQ celebration at Fremont Peak Observatory, met Rob whom I need to confer with about doing star parties and getting time on the 30" FPO Scope. And, met Yanzhe Liu who is gifting me a Meade f/6.3 OTA. Thank you! Then, we hurried back off the mountain, picking sites to get the Ulrike Occultation and also the Ilmari event which was 45 minutes later, from the same sites.

Richard Nolthenius

I was so busy this mornig and early afternoon getting Plan A, B, C, and D revised or abandoned, that I forgot to actually photograph the charts for Ulrike for myself. I did post them on the web, but since I could not access the web from my site (SOS only on T-Mobile), and I ran out of time to try and go back to Kirk's station and get the charts from him, that I did not have charts and could not get on-target. No data from me

Kirk Bender

Got data, from a site 3 miles north of me, and 1.5 miles south of Bernard. I got at 1.3289s event for Ulrike on Hwy 25, Oct 12, at 1x.
There was only one other star bright enough for tracking. There's a tall vertical spike at the beginning of the D but not at the R, and there are similar spikes throughout the curve so it's probably noise.


magDrop report: percentDrop: 96.4  magDrop: 3.617  +/- 0.874  (0.95 ci)

DNR: 2.03

D time: [03:22:41.7146]
D: 0.6800 containment intervals:  {+/- 0.0057} seconds
D: 0.9500 containment intervals:  {+/- 0.0177} seconds
D: 0.9973 containment intervals:  {+/- 0.0479} seconds

R time: [03:22:43.0435]
R: 0.6800 containment intervals:  {+/- 0.0057} seconds
R: 0.9500 containment intervals:  {+/- 0.0177} seconds
R: 0.9973 containment intervals:  {+/- 0.0479} seconds

Duration (R - D): 1.3289 seconds
Duration: 0.6800 containment intervals:  {+/- 0.0087} seconds
Duration: 0.9500 containment intervals:  {+/- 0.0225} seconds
Duration: 0.9973 containment intervals:  {+/- 0.0503} seconds


 

         

 

Bernard Huynh

Got data on both occultations, and a solid positive on Ulrike of about 1s or maybe a bit less.