Every once in a while you get an extraordinary night 10/10/98
Observing report for Plettstone located in Bear Valley California
by
We arrived at Plettstone pretty late on Friday night so I decided not to
open up the observatory. Instead, I pulled out the lounge chair and did
astronomy the old fashioned way... with my naked eyes. The air seemed
incredibly clear and the moon had a high contrast against the blackness of
the sky. I thought that had I been there earlier, the seeing and
transparency would have been outstanding. I was hoping that Saturday would
be good based on the conditions I was enjoying.
Saturday morning, Paul had an occasion to meet some of our neighbors for the
first time. (It's kind of a funny story but that is left best to friends).
I asked him to invite them over for some viewing later in the evening. They
accepted.
Just after sundown, I rolled off the top of the observatory to get things to
cool down. Since this was a "moon" night, I had planned to do a little
observing for the first part of the evening and then do some maintenance and
calibration after the moon came up. I've had a RA drift problem that I have
never been able to resolve.
The two primary instruments for the evening were a C11 SCT and Celestron
80mm refractor mounted on a Losmandy G11 equaorial head. I had just obtained
the used refractor on Thursday to use as a guiding scope. I have been using
a 100mm refractor for a guide scope and the 80mm weighs less. I thought
that this may help alleviate the RA drift problem. The last time I visited
the observatory, I had spent a great deal of time to accurately collimate
the C11 using a CCD camera and a triple hole mask. I was looking forward to
see the results.
Just as the stars came out, our neighbors Stan and Sue arrived in their
pickup truck. I took a quick peek at Jupiter. The warm currents in the sky
had not settled and the planet's disk was ablaze with fire. This was not
the image to introduce new people to the sky. Instead we focused on bright
favorites. We started out with the great Hercules globular cluster (M13).
Sue was amazed at the sight and sqeeled with delight at seeing something so
extraordinary. I still have never seen a photograph that does these bright
globular clusters justice.
For the next hour or so, we shared views of the bright nebulae, the ring in
Lyra, the swan and lagoon in Sagitarius, and the dumbell. Stan mentioined
that he had a telescope and had never been able to get it to work so he had
never seen anything. After a brief period of questions and answers, I
deduced he had an equatorial mount and explained to him how to do a simple
polar allignment. I also informed him that all of the things we saw could
be seen in his scope quite easily.
Since my observing passion is galaxies, we spent some time talking about
them and looking at a couple of them. We looked at Andromeda and its
companinons. I even showed them ngc7331. While I was moving the scope, I
took a quick peak at Stephan's Quintet. Lovely. Easy target. Was this sky
great or what?
I love showing people the sky for the first time. Especially folks who are
really interested. We had a chance to get to know each other some. Paul and
Stan's jokes and laughter filled the valley.
Just as Saturn raised its head over the treeline in the east, I pointed the
scopes back towards Jupiter. WOW! A view reminiscent of what I've seen
through a friends 7" AP refractor under great conditions at the peak. The
seeing and transparency were excellent. As an added bonus, the "great red
spot" was plainly visible. It was yelling at us... it was that clear. Some
beautiful blue festoons gracefully transgressed into the equatorial band.
This was a sight for the books. I promised myself to come back after my
visitors left.
Saturn had easily cleared the tree line and I moved the scopes for a peak.
My new friends hand another knock your socks off view of a planet. Saturn
was still in the lower atmosphere but the rings were clearly cut into
several divisions and the equatorial bands were undeniable. We oohed and
ahed for several minutes.
We had spent two and half hours looking at fewer than 15 objects. It's nice
to be able to share these sights and talk about them. I love to describe
them to visitors and attempt to explain how they come to be. Soon our
guests left, and I was alone with the dark night.
I swung back to Jupiter and watched as the spot started to move behind the
planet. Then I got back to work. The moon was coming up and I wanted to get
a good focus with my CCD for next week's marathon run. I spent several
minutes getting the beastie focused and shot a few tricolor images. One of
these days, I'm gong to figure out how to get those to look good (of the
moon).
I had planned to spend some time with drift allignment but the permanent
installation just doesn't change that much. After running some tests for a
half hour or so, I decided to see what the CCD could do on something close
to the moon. Orion's great nebulae were up and were only 30 to 40 degrees
away from the 3rd quarter moon.
I focused the instruments on the trapezium. My objective here was not to
get a shot of M42 (the large nebula in Orion). I wanted to see what was in
the trapezium region. Every shot I have ever seen of M42 is completely
washed out. After some brief tests with exposures, I decided a 15 second
exposure through filters would keep those bright stars in check. I ran a
total of 60 exposures, 20 each through red, green, and blue filters. The
process took hours it seems. I looked at the clock... 4AM. I couldn't
believe it.
I had to combine the images before I went to bed however... I wanted to see
what I had. The results were not stunning but nevertheless, impressive.
The SX H5116 has a very low dark current and the sumation of so many
exposures did not seem to add any low level noise. In addition, I had never
seen this area of the sky photographed. The clouds of gas reflect an
enormous amount of blue light. I had very little red and practically no
green in the nebula. I am very excited to get back home and do some
processing on these images.
At 5:00 AM, I shut down the computers and other equipment, buttoned up the
observatory, and went to bed. I couldn't go to sleep right away. The
excitement of a great observing/CCD session kept me awake for some time.
Every once in a while, you get an extraordinary night.
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