2017 27th Annual Grand Canyon Star Party
DAY FOUR - Success
Location: Grand Canyon Visitor Center, South Rim of Grand Canyon, AZ, about
340 miles north of home in Tucson, about 7000 ft. elevation
Weather: Just keep adding a couple of degrees to each day's report. The
cloud cover that kept yesterday a bit cooler was gone, so mid-90s is probably
understating and setting up on black asphalt did not lessen the oven-like
conditions.
Seeing and Transparency: Personally, the seeing is very stable but the
transparency is quite obscurred by moisture in the air and local wildfires.
In Tucson, at 2500 feet altitude, the camera settings that provide
attractive views can't even pull in the Deep Sky Object images. I'm having to
bump
the gain and integration times considerably to get an image, and I'm not
alone in the observation.
Equipment:
10" Meade SCT on Celestron AVX mount
Mallincam Xterminator video system on the 10", 19" QFX LCD monitor.
Cloud cover got in the way of the plan to polar align yesterday, so after
tonight's talk I ran out and used a planetarium image with a Telrad overlay
to get an approximate starting point. In addition, I ignored the AVX user
guide and did my own alignment star selection and between the two
corrections, alignment was pretty good, finally, after three nights of fuss.
I only had the mount for three days when I left for GCSP. It was an
emergency fill in for the failed Orion Atlas that failed so catastrophically.
The main issues I have with the AVX is, as usual with advanced astronomical
equipment, there is a learning curve. Compounding the issue was absolute
errors in the manual. Three issues come to mind. First, since about 2012,
the manual has stated that there is a bubble level in the tripod. NOPE.
Starizona has an aftermarket item that I should have bought with the mount,
but didn't know about it. Fortunately, my bulls-eye bubble lever from the
Atlas fits nicely inside the tripod head so I was able to get it levelled.
Second, it is not explicit that there is no polar scope included; it also
is an after-purchase acquisition I wasn't aware of. Finally, the initial
alignment instructions recommended taking the recommended alignment and
calibration stars in the order offered, if possible. But the presentation is
in alphabetical order by quadrant, with a magnitude bias thrown in. As a
result, my two star alignment and two calibration star additions were two
objects in each half of the sky, but the DEC values were only about 3 degrees
offset; not possible to get a decent alignment.
First off, we started off the evening with the night talk by Dean Regas,
Astronomer and Outreach head at Cincinnati Observatory as well as being the
co-host of the PBS nightly Star Gazer television short, following in the
footsteps of the late Jack Horkeimer. Dean is an awesome communicator. He
presented a fascinating unveiling of the size of the universe, starting
locally with the Earth and Moon, and using Mintaka and Starry Night Pro,
expanded the exposition from local, then the rocky planets, out to the gas
giants, the sun's long reach and out to the Oort cloud, then local stars, our
galaxy out to other galaxies, and finally out the the full Universe we know,
in many different alternative points of view, well laced with humor and at a
scale where the elementary school children in our audience were very
actively involved. An awesome presentation, and we have him back again
tonight.
After the talk, my path to success was to first do a rough polar using the
Telrad while the mount was in home position, and then use an algorithm I'd
put together years ago to optimize star selections. With a three star
alignment (Albireo and Unulkalhai in the East, Regulus in the West at about
9:15 PM MST, and crossed my fingers. M13, the Hercules Cluster, was my first
pick and bang, nearly in the center of the FOV. I did have to jump the
integration time to get a good image due to the fire debris, but it filled
about 80% of the vertical view. I was able to tailor the time to get pinpoint
stars and selected red giants in the cluster, just the way it should look.
I spent the next 90 minutes with about 200 visitors passing by and teaching
the nature of globular clusters orbiting the outer confines of the Milky
Way, yet having ages around 12 billion years compared to the 7.5 billion
years of our galaxy. Great discussions with the folks so excited to be with
us. Wayne Thomas was set up next to me, and happened to be set on M4, the
globular cluster next to Antares in Scorpius. We were able to compare the
possible genesis of the objects, and havint Antares available allowed the
discussion of naming conventions. We know our next outer planet as Mars,
but the Greek name for the planet was Ares, also the god of war. Now one of
the etymmologies of Antares comes into context; the place where the spirits
of soldiers who died in battle have gone to their permanent rest, leaving
the star with a reddish hue. Quite a bit of other cultural discussions
occured, as usual when I get customers (victims?) to talk with. By about 11
PM I tried another target, M27, The Dumbbell, in Vulpecula, and got pretty
close but it needed a lot of tinkering with settings. I then ended by
jumping over to M57, the Ring Nebula, and it seemed I couldn't mess it up; lots
of flexibility in setiings, but still significantly more integration time
due to the hazy, although bright, stars. One indication to me of the
reduced transparency was Albireo. It was barely visible in the Telrad. It
will
be interesting tomorrow to use the internal software and improve the polar
alignment and realign, then try some galaxies. At least now I can point to
eye candy!
Jim O'Connor
South Rim Coordinator
Grand Canyon Star Party
_gcsp@tucsonastronomy.org_ (mailto:gcsp@xxxxxxxxxxxxxxxxxxx)
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