The Occultation of a W=10.0 Star for 0.2s by Asteroid 2002 JF148

Wed eve June 3, 2026 at 10:20:38pm

OWc page

 

This is a bright occultation, but lasts only 0.2s. Skies are predicted to be clear. The rank is not super great, so a miss is possible. But, the time is convenient and worth a go. It would help refine the orbit of thie asteroid.

Alt=21, Az=131 in the southeast, in Ophiuchus, 1 degree to the right of Eta Oph = Salib, and 11 degrees left of Antares.

     

Cloud forcast: GFS prediction
Cloud forecast: ECMWF prediction

The experience is that the ECMWF prediction is the more accurate; it has finer resolution, and also includes the effects of clouds due to mountains, so better does orographic lifting etc. You can see the two predictions differ quite a bit. The larger scale prediction looks like we're conflicting between incoming fog, and a high pressure dome which is keeping it away. If fog stays away, Jordan has a good chance at home. I'll probably go north, depending on the Zoom Earth images before having to head out. Bernard may be able to get from home too.

Results:

Richard Nolthenius

I had clear, moonless, calm weather. No clouds. Got a good recording at 1x, from Treetop Lane off Graham Hill. Saw a ~0.2s event on the Lenovo screen. This was just south of hte predicted southern limit. Looks like a south shift, as Kirk inside the path had a miss. Mine not reduced yet.

         

 

Kirk Bender

Observed from Sky Park in Scotts Valley. I don't see an event for 2002 JF148, 1x at Sky Park NW lawn on June 3rd. Curve is noisy, there was strong flickering. I tried several mask sizes in PyMovie, but none showed an event. PyOTE detectability tool reports an event as short as 0.17s would likely be detectable, max predicted was 0.21. Either a miss or too short to detect. Rank was not great, I was not far from center, but at Treetop Dr. you were south of the path, closer to the 1-sigma line.  We were separated by about a path width, so if you got a positive, it's possible I could get a negative.


Karl von Ahnen

reported playback looked like a miss, but not reduced yet.