2016 Grand Canyon Star Party - Day 4 - The Visitors Are Really Into This!

[Skylook123]

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 weather started moving in late. 

Seeing and Transparency: Transparency very occulted by wildfires, causing increased integration times.  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 a 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 incorrect fixes.  First, when setting the integration time on the wireless controller, I hit the wrong field, and applied an 11 second interval 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 flicker 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 flicker 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 above prior year audiences.  Now if I could only get out of my own way and not cause my own troubles!

[orion25]

Interesting report, Jim! Despite the unfortunate mishaps and foibles, it turned out to be an informative (and memorable) experience for the visitors. And it will always make for a great astronomy tale!

[rockystar]

some great reports coming out of your star party, and such a magnificent venue.

hope the repairs to the scope aren't too expensive.

[SacRiker]

Great report. Reading about your dob overturning in the wind made me feel a little ill. The other day I was carrying my 8" back into the house and it caught the doorframe, making a sickening sound...I can only imagine how scary it would be to see the whole thing laying on the ground!

[Skylook123]

Thank you all for the comments.  My secondary cage cracks incident of wind effects about 12 years ago was repaired with carpenter's glue and some large clamps.  Unfortunately, the recent blow-over will need major rebuilding.  Fortunately, their mirror was undamaged.