Grand Canyon Star Party 2005 - Long

Event: Grand Canyon Star Party

Date: June 4-11, 2005

Location: One quarter mile south of Yavapai Point, South Rim of Grand
Canyon, AZ, about 340 miles north of home in Tucson, about 7000 ft elevation

Weather: Most nights, temperatures in low 30s with winds 20-35 MPH with
gusts into the 40s. At least one night with overcast and rain.

Seeing: and Transparency: Generaly excellent; between ground level wind
gusts.

Equipment: 18" f/5 2286mm Tectron newtonian truss dob, Sky Commander DSCs,
50mm Orion Plossl (46X, 1.09 deg FOV), 22mm TV Panoptic (104X, 0.65deg FOV),
18mm Celestron Ultima (127X, 0.39 FOV), 9mm TV Nagler (254X, 0.32 FOV), 2X
Celestron Big Barlow, Lumicon Ultra High Contrast and OIII filters,
Celestron Ultima 10x50 binoculars, Vanguard Panhead tripod.



DAY ONE OF SEVEN - What ELSE Did We Forget?

GCSP is an annual collaboration between the National Park Service, the
Tucson Amateur Astronomy Association, and astronomers from throughout the
Southwest to bring observational astronomy to the Park visitors. This was
our third year in a row, staying seven of the eight nights this time.



Dean Ketelsen once again did a great coordinating of both daytime and
nighttime astronomy outreach at the Park. And outreach it is; we observers
are privileged to serve as "National Park Service Interpretive Volunteers,"
the NPS publicizes the event, and from the time the 8PM slide show at the
Yavapai Observation Station is finished until about Midnight, the crowds
come by to ooh and aah.



We arrived in the early afternoon after a leisurely six hour drive from
Tucson. We first went to the usual observing site, a grassy spot co-located
with the Yavapai Observing Point, and unpacked the scope. Imagine my
surprise to find the truss tubes were still back in Tucson! Somehow, in the
arranging of the pickup bed contents the ski pole back of tubes were left
propped against the garage door track. Concurrent with this discovery was
Susan's observation that she hadn't packed for the cold; in previous years
the event was later in the month so her wardrobe assumed about 20 degrees
too warm. She volunteered to drive back home, stay overnight, and bring up
the poles and a revised wardrobe. Meanwhile, I would hold the room and the
telescope site (lots of competition for space), set up the 10x50s and tripod
next to the scope box, and enjoy a night of wide field views.



The trip back only took 5 hours; she tried an alternate route that didn't
seem to be shorter, but shaved an hour off the trip. She was back in Tucson
by 10 PM. Up at Yavapai, the winds started strong and gusted stronger,
while the temperatures fell well below any comfort for experienced
observers, much less park visitors. After an hour or so, I packed up the
binocs and headed back to the room. I did an inventory of the support box,
and found that the new DSC cable was missing (one channel of the old one had
stopped working)! So, when she called to let me know she had made it back
to Tucson earlier than we thought, I asked her to check around the house for
the new cable. No luck. Then, with a brain storm, I asked her to check the
LX-5 OTA transporter box and there it was! I had the LX-5 cable with me.
Go figure. All worked out.



Down at the Pit where we were set up were many more scopes than previous
years. Plus the usual eclectic group up on the main parking area.
Alongside my 18" Tectron, this year there were three 20" Obsessions along
with a C14, 16" Meade Starfinder, many newtonians in the 8" - 12.5" class on
a variety of equatorial or dobsonian mounts, several C8s, and later in the
week Meade 10" and 16" LX200 GPSs. Up top was an even broader distribution,
with up to 24" apertures in dob/newts and several C11s and C14s. Around
70-80 total between the two locations.



DAYS TWO THROUGH FIVE - Nice Views When You Can Get Them



The next four nights were highlighted by a few minor glitches, great
performance in general for all the equipment, and a bit of learning. Very
cold, very gusty, lots of wind, and moments of incredible clarity and
awesome images.



On the first night, the biggest discovery was that the rocker box was
awfully sticky in azimuth. This translated into quite a bit of offset error
in the Sky Commander DSC behavior.



Regarding the Sky Commander. I decided to make use of the ability to load a
user list into the box by using my observing laptop. I bought an RJ-11
(phone jack) to RS-232 (computer serial port) interface plug from Software
Bisque. Then I converted my observing list into an ASCII file of RA/DEC
values and broke it into 59 item segments (the max number of user list items
for the Sky Commander). Finally, I loaded the list from my observing
computer into the box. Took seconds. Plus, with the serial connection
maintained, I could velcro the small computer to the mirror box and
continuously display cross-hairs of where I was pointed in real time. This
worked quite well. I was able to modify the list as the need arose (e.g.
daily changes to comet ephemeris) and was able to bag three comets each
night easily.



The first four nights would be pretty similar. Forget the observing list;
the purpose is to introduce the populace to the night sky, so although I
abandoned most of the Arp/Hickson objects I had set up, it was great to
bounce around from the Sombrero (M104) to the Ring (M57), two globular
clusters (M53, M13), and the Whirlpool (M51) Each was positively stunning.
At around 10 PM each night, Markharian's Chain was available with only a
single step climb on the ladder. Locking in on M84 fixed one end of the
chain, then a slow walk upward in elevation revealed eyepiece after eyepiece
full of galaxies due to the moderate (18") aperture. Only about 10 percent
of the time was useable, however, due to the tremendous winds. The upper
atmosphere was dead calm, and the best seeing/viewing I can remember. I was
able to go to 508X with crystal clear images whenever the gusts would
subside.



The truss dobs weren't the only victims of the winds. Anecdotally, even the
C-14s on hefty mounts were having stability problems. I heard of some
observers keeping the power around 100x just to keep the image in the
eyepiece during the constant gusts.



After the "dragging" problem in azimuth, on the second night I went to the
site early and disassembled the scope. In particular, I took the ground
board off of the rocker box. There were two problems. First, the wind had
kicked up a tremendous amount of dirt, much of which was caked between the
Teflon and Ebony Star azimuth interface. Second, the pivot bolt/azimuth
encoder setup is backward from my previous dobs. The pivot pin is a top-hat
shaped solid piece that is locked into the ground feet with two hex bolts.
The encoder axle is then locked into the top of the hat. Thus, the hat
remains stationary while the rocker box moves. Infortunately, there is no
sleeve through the box, nor is there any shim/bearing surface under the top
hat; strictly aluminum on wood. So it scrapes along, causing jerky motions
and making it very hard to center objects in the eyepiece. I disassembled
all the pieces, cleaned out all of the dirt, and put a thin coating of wax
(only had Pledge; will use paste wax in the future) on the three Teflon pads
and under the top hat. In addition, to keep the dust/dirt impingement down,
I folded up the Scope Koat weather cover and placed it under the box. What
an amazing difference! The Sky Commander became highly accurate; so much so
that I was able to hop around at 254X with no problem nailing all objects.
Now I've got to get a bushing in the pivot hole and some kind of bearing
surface under the top hat (even if it's just a couple of circles cut from a
plastic jug).



On night five we had a fantastic GRS display on Jupiter. With the 9mm
Nagler eyepiece, even folks who had never looked through a scope were
acclaiming the view. As I said, though, about 90% of the time the wind
gusts made using the scope impossible. I finally found I could place the
objects off center and hold the nose of the scope in the gusts and let the
image drift through; this made better use of the time.



One night I did step through about 35 objects of the 156 I had scheduled,
but since the nights were so unpleasant I shut down when the visitors
stopped coming by; no point in a list this year.



DAY SIX - Rain.



Enough said. The previous night I disassembled and packed the scope,
wrapped it all up in the weather coat, and took it as a night for napping.



DAY SEVEN - Dead Calm, But Short



The night was predicted to be clear and calm. Most of the day the winds
were quite reduced, but scattered clouds threatened until sundown when the
sky cleared. The night was fantastic for showing off showpiece astronomical
objects. No problem with 504X. While it was available, showed off the
sliver of a moon at about 45X; it was a beautiful image even though it took
a bit of bending over to see it. Quite a special night for about two hours.
Then, rising clouds from all quadrants. By 11 PM, however, the entire sky
was shut down. Since the weather was predicted to be isolated thunderstorms
for the next two nights, most of us permanently packed up. We left the next
morning.



I did check out about 15 double stars from a list I created; all were
exceptionally attractive; got to revisit these.



So, the views were fantastic, the wind was frustrating, and the freezing
cold was unexpected. Still, a great experience.



Many thanks again to Dean Ketelsen and the National Park Service.

Skylook123 wrote:
Event: Grand Canyon Star Party

Date: June 4-11, 2005

....major snip

Many thanks again to Dean Ketelsen and the National Park Service.


Large ditto to that. I was around for the first night, watching
Dean run around and keep things from getting wildly out of hand
(there were 200+ people at the dusk talk). Views in everyone's
telescopes were stunning - what a treat not to have to imagine
the spiral pattern in M51. But it was M13 in the 24-inch that
absolutely took my breath away. Some of the views even impressed
my 12-year-old who I talked into coming up from the hotel in Williams
for the eveing...

Bill Keel