2016 26th Annual Grand Canyon Star Party In Memory Of Joe Orr
DAY FOUR - Clumsy Me, Great Visitors
Location: Grand Canyon Visitor Center, South Rim of Grand Canyon, AZ, about
340 miles north of home in Tucson, about 7000 ft. elevation
Weather: 93F mid-day, 80F at sunset, 54F when I quit near midnight. A few
clouds all around at sunset, but clearing out early until western weatner
started moving in late.
Seeing and Transparency: Transparency very occulted. Very steady skies.
There were some strong gusts in early afternoon that knocked over and
damaged one large dob.
Equipment:
10" Meade SCT on Atlas EQ-G mount
Mallincam Xterminator video system on the 10", 19" QFX LCD monitor.
Pretty much a boring day, except for a pesky food poisoning! Lost a LOT
of moisture, but nothing that a couple of big Gatorades didn't partially
fix. I went up to the site early to provide an interview for a YouTube
project. It was great to talk with a young college student who is an AV
Production major who just happens to be an amateur astronomer as well as
running a
YouTube site for her college. One unfortunate thing I noticed as I came
into the lot early and set up next to my scope for the interview was that
earlier wind gusts had lifted an astronomer's large tube dob out of the rocker
box and dumped it on the ground. The mirror was OK, but the mirror box,
elevation bearings, and other bits need to be reworked. I had the same
thing happen at our old site in 2004. I my 18" truss dob secured, I thought,
but I allowed no rotation and the angle of the tube was about 25 degrees.
During the night, the wind shifted 180 degrees, got under the tube with the
shroud making a great sail, and lifted the whole assembly out of the rocker
box and dropped it onto the ground beside it. The next day, I found my
primary mirror half way up the truss on the ground, and the upper ring of the
secondary cage cracked in multiple places. NOT fun. One just can't allow
the wind to get under the tube, so stowing at a lower angle is essential.
Yesterday's event happened to a tube that was fixed almost vertical.
At the appointed time, I went into the theater for the night talk; tonight
it was Marilyn Unruh, who owns The Booknook science book store in Prescott
and is a tremendous outreach practitioner and educator. She does her talk
without any slides, breaking the presentation down into Telescopes as Time
Machines (relative distances close to home and across the universe), Have
You Seen The Shadow Of The Earth (the sunrise/sunset effect of the Earth
shadow against the debris of the solar system, plus the shadows cast by
various astronomical features), and Using Your Five Senses for Astronomy, a
very
clever depiction of listening to the cosmic background, seeing the night
sky, smelling and tasting the air which was once inside a star, and using
your hand to measure angular distances in the sky. Always a well-received
talk.
I went back to the scope and, since it was dark, I put it on the Moon to
start things off. It was a nice three day old image, showing the small
impact craters on the limb. Due to the nature of the SCT image flips and the
focal reducer on the camera, I can rotate the camera to orient the image on
the screen so that it matches the naked eye view of the moon. It always
surprises me when visitors enjoy a view at this stage of lunation that most of
us veterans take for granted.
With a break in the crowd, I moved over and aligned on Vega and dropped to
the Ring Nebula, M57. Once again it was gorgeous, a red hydrogen wrappper
and the wider blue-green segment surrounding the white dwarf at the center.
Thus began the running discussion of stellar evolution and how our Sun
will join the ranks of mid-sized stars consuming their fuel.
At a break in the flow, I went over to the Dumbbell planetary nebula. It
was moderately off center, so I started to try to bring it into better view,
when I kicked the tripod, greatly disturbing all alignment. I parked it,
went to check polar alignment, and it was significantly in error. After
taking care of that, I went back to Vega and aligned and did a focus check.
When I went back down to the Ring, I made a major error that caused a long
time of chasing gremlins and applying incorred fixes. First, when setting
the integration time on the wireless controller, I hit the wrong field,
and applied an 11 second interval jump time. So I was getting the previous
six second time shown in the image from the correct field, but a drop off the
screen of the image. I was thinking it was a different problem, so I
recycled the camera. Same story. I misinterpreted the blanking of the
interval delay on the receiver to imply the receiver battery was dying, so I
changed batteries. I had to chase the channel of the receiver to the one I
use
for this camera, got it all running, and there was the blanking again. I
checked the transmitter, and DUH, saw the mistake. After I got that fixed,
and went back to the Ring, it was again gorgeous. What a waste of time!
The crowd coming by was stunned at the beauty, and for the next hour we had
a stream of people with great questions after my narrative, and almost
everyone profuse with their thanks for the view and the education.
It was encouraging to have strong reaction to the stellar life cycle
explanation, with some deep questions like determining the velocity of
expansion
and the shape of the planetary. I used an example of pressure waves moving
through media. The pressure wave is affected by the density of the
medium. When the initial "sneeze" of the increased stellar wind begins the
end
of life for the star, the outer hydrogen is moving in a vacuum but the
succeeding oxygen wave is now moving through matter, and the new wave begins to
catch up. The shape is related to the magnetic fields of the original star
at end of life, and the nature of the stellar wind being blown off the
dying star. Lots of good exposition, with lots of great questions.
The crowd finally evaporated, and so did grandson Stephen and I. At the
suggestion of a visitor, and my echo shouted over to him, John Carter
shifted his galaxy tour to NGC4125 for a view of the supernova. The 275 or so
people I was able to actually SHOW something to seemed a cut aboue prior year
audiences. Now if I could only get out of my own way and not cause my own
troubles!
Jim O'Connor
South Rim Coordinator
Grand Canyon Star Party
gcsp@xxxxxxxxxxxxxxxxxxx
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