The Klio Occultation - Sept 6/7, 2010
This
event was at the tail end of a tough day - did a very mountainous
bike ride in Big Sur with the Delucchi's, picked up the 10" scope
on the way home from their place, took a shower at home and then drove
up to Bonny Doon. Decided to observe from the Presbyterian Church to save
some driving and sleep time on the back end. The occultation was at 9:40pm,
with odds about 40% from the church. My Canon ZR45mc camcorder failed on
its last attempts so I didn't even try to record it. Did it visual with
WWV recording. It was foggy in Santa Cruz but the marine layer was clearly
low and the church was well above, in beautiful clear, dark, calm conditions
and good seeing. The target was easy to follow, with limiting magnitude
at 12.5 and the target at 11.1, with a drop of 1.8 mags, just below visibility.
The stars were steady with no scintillation visible. At 4:40:02.5 I saw
a short blink and shouted "D!", but it lasted only 1/4 second,
so was it a rare seeing blip, or real? I think it was real, but of course
I can't be sure. Unfortunately, Walt Morgan at track 39S had a miss. I
was at 69.4S, so if my event was real, it means the asteroid's northern
limit shifted to 69.4S. Derek would've been the key, but he was sick and
couldn't observe. On tape at the time, I gave it a probability of being
real of 85-90%. However, both John Westfall and Walt Morgan had misses
from closer to the centerline, so a large shift did indeed happen.
Here's my excel
report. And here's the sky
plane profile for our observations.
This
event was at the tail end of a tough day - did a very mountainous
bike ride in Big Sur with the Delucchi's, picked up the 10" scope
on the way home from their place, took a shower at home and then drove
up to Bonny Doon. Decided to observe from the Presbyterian Church to save
some driving and sleep time on the back end. The occultation was at 9:40pm,
with odds about 40% from the church. My Canon ZR45mc camcorder failed on
its last attempts so I didn't even try to record it. Did it visual with
WWV recording. It was foggy in Santa Cruz but the marine layer was clearly
low and the church was well above, in beautiful clear, dark, calm conditions
and good seeing. The target was easy to follow, with limiting magnitude
at 12.5 and the target at 11.1, with a drop of 1.8 mags, just below visibility.
The stars were steady with no scintillation visible. At 4:40:02.5 I saw
a short blink and shouted "D!", but it lasted only 1/4 second,
so was it a rare seeing blip, or real? I think it was real, but of course
I can't be sure. Unfortunately, Walt Morgan at track 39S had a miss. I
was at 69.4S, so if my event was real, it means the asteroid's northern
limit shifted to 69.4S. Derek would've been the key, but he was sick and
couldn't observe. On tape at the time, I gave it a probability of being
real of 85-90%. However, both John Westfall and Walt Morgan had misses
from closer to the centerline, so a large shift did indeed happen.
Here's my excel
report. And here's the sky
plane profile for our observations. 