April 2008 - Utah-Astronomy - mailman.xmission.com

OT: Parachutes and rocket packs again
by Canopus56 26 Apr '08

26 Apr '08

Something to make the commute a little easier and more entertaining: Attack Wing: Glider Makes Waves With Stealth and Speed http://www.foxnews.com/story/0,2933,352477,00.html Attack wing glider video: http://www.foxnews.com/video2/video08.html?videoId=0ce238b2-cc7d-4c94-9b94-… - Kurt ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

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Re: [Utah-astronomy] When laser operators go wild
by Canopus56 25 Apr '08

25 Apr '08

Chuck, > Well, New South Wales, at least. It doesn't appear > to be an outright ban, but owners must carry a > permit. Just noting it for the entertainment value. Can't wait to have to get my concealed GLP permit. But, ya know, those amateur astronomers are such a rough, shifty looking lot. -:) Kurt ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

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When laser operators go wild
by Patrick Wiggins 25 Apr '08

25 Apr '08

Moon advertising (he's kidding, right?). :) http://www.moonvertising.com Enjoy, patrick

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Hubble images, Nice!
by diveboss＠xmission.com 25 Apr '08

25 Apr '08

http://www.foxnews.com/story/0,2933,352439,00.html

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SLAS Arcadia Elementary Star Party has been Canceled
by Michael Morrison 24 Apr '08

24 Apr '08

Hi, Dan Boone has canceled the Arcadia Elementary star party scheduled for tonight. Mike Morrison

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Re: [Utah-astronomy] Laser collimator
by Canopus56 24 Apr '08

24 Apr '08

Chuck wrote: > Got it now, Don and Kurt. Mental block! Actually it > can rotate to any viewing angle and still be > useful. Using the blug with a closed-tube Newt presents some difficulties in seeing the blug from the back-end or primary mirror end of the scope. Here's what I do. 1) Use an extendable automechanic mirror to see down the tube: http://gallery.utahastronomy.com/main.php?g2_itemId=11124 2) Use the secondary "laser halo" to do the last fine tune of the alignment using the primary mirror. This tip isn't in Glatter's instructions; it is something that I homebrewed. The very last final tweak in high-end laser collimation is to get the secondary centered in the laser light cone coming reflecting off the primary. This is most easily seen in a darkened room. If the scope is collimated, the secondary will be framed in a halo of laser light that is concentric. If is off the slightest bit, the laser halo framing the secondary will be off-center and elliptical. I don't have a photograph, but here is a sketch of what the halo looks like when you peer down the front of the closed tube - http://gallery.utahastronomy.com/main.php?g2_itemId=11139 This final tweak is made with a fine adjustment to the primary mirror knobs made while standing behind the primary mirror. So, how do you see the halo with a closed Newt tube when standing behind the primary mirror? I have a couple of techniques. If I am indoors and there is a convenient wall near the scope, just point the open tube towards the wall in a darkened room - the laser halo and secondary shadow will project on the wall. I also have used a piece of paper taped to a tripod and posted in front of the tube - http://gallery.utahastronomy.com/main.php?g2_itemId=11127 - or a pillow case or T-shirt draped over a chair. Although the above picture is in the daylight, this adjustment is usually done in a darkened room or outside at night. I also have some other homebrew tips for lurkers for collimating a fast Newt that depart from the instructions included with Glatter's laser collimators. Glatter's approach is to align everything relative to the flat surface of the top of the focuser tube - using a big carpenters T-square to set the initial positions of the secondary mirror and the primary mirror. Everything is measured relative to the focuser tube top. Glatter's T-square approach proved too cumbersome for me, so I home brewed the following method which emphasizes minimizing collimation errors relative to the center line of the telescope tube. Again, most of this is intended towards collimating and aligning a GEM mounted Newt. It is probably too much effort for truss dob or ordinary box dob. I modified my scope cover by drilling two holes in it - one at the center and one off-axis. http://gallery.utahastronomy.com/main.php?g2_itemId=11130 The black duct tape is used to cover the holes during scope storage. On the front of the tube at the secondary mirror, the cover and the center hole is used to initially rough align the secondary mirror assembly along the telescope tube's central axis. The Cheshire and flashlight are aids to seeing the secondary mirror in the now dark tube. http://gallery.utahastronomy.com/main.php?g2_itemId=11133 On the back of the tube at the primary mirror, the cover, off-axis hole and the straw-depth indicator, are used to initially roughly align the primary mirror perpendicular to the central axis of the telescope tube. http://gallery.utahastronomy.com/main.php?g2_itemId=11136 Then I rough align the secondary mirror in the length dimension along the tube's central axis by visual sighting both within the main tube and by sighting down the focuser tube. The mirror is offset about 1/8" up-tube per Nils Olaf Carlin's article on parallax error in the secondary mirror. This is only done on the first collimation. I do not do this rough alignment during followup maintenance. http://gallery.utahastronomy.com/main.php?g2_itemId=11142 Once these preliminary mirror positions are set, then I use the laser colliminator per Glatter's instructions, except for the home brewed final adjustment mentioned above using the laser halo as a guide. All the adjustments are made to the maximum extent possible only using the secondary mirror. This forces the collimation axis to be co-incident with the central axis of the telescope tube and the primary mirror that is sitting perpendicular to the tube axis. The benefit of this approach, again limited to a GEM mounted Newt, is that the central axis of the tube becomes the fiducial axis for collimation and subsequent cone error correction. When I go to adjust the cone error using the Allen bolts on the mounting bar - http://gallery.utahastronomy.com/main.php?g2_itemId=11145 - I only needed to turn the adjustment bolts at most 1 to 2 turns on a two of the four Allen bolts before cone error is minimized. My Newt now easily adjusts for cone error almost like it was a refractor. For lurkers, some of the above is homebrewed. Use at your own peril. - Kurt ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

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SLAS - Arcadia Elementary School Star Party
by Michael Morrison 24 Apr '08

24 Apr '08

Hi, Calling for a Celestron CPC operator to help with tomorrow night's school star party. The teacher in charge of the star party, Dan Boone, said that the school has a new CPC 11" scope and he would like some help with getting it set up. I found the simplest way to get to Arcadia is to travel east or west bound on 4700 South to Simper Lane (3400 W). Turn southbound on Simper to 4850 South. The school is across the intersection at 4850 South and 3461 West. The star party is from dusk to 10:00 p.m. weather permitting. Clear Skies, Mike Morrison

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Story Musgrave to speak at Bryce Fest this year
by Patrick Wiggins 23 Apr '08

23 Apr '08

I just received this from Ranger Kevin Poe at Bryce Canyon. patrick +++++ Spread the news far and wide through SLAS that we have Story Musgrave (6 time shuttle astronaut and "mother earth defender") for the 8th Annual Astronomy Festival's Keynote Speaker! First night of the festival Wednesday June 25 we will have Story and the telescopes (I'm hoping many from SLAS can find a way to make it down here that early in the week) in Panguitch so that we can take advantage of the 1500 seat capacity of the town's Indoor Rodeo Arena. The neighboring town park has a great place to set up 25-30 scopes (I'll email pictures next week) and I'm pretty sure I can get the town to institute a voluntary "black out" for that night. Nevertheless it won't be as dark as Bryce (and the moon rises at 00:35) but this has the potential to be a most excellent outreach opportunity. Perhaps this event will serve as a launching point for future efforts to institute a county-wide lighting ordinance and to an encourage our local power company, Garkane, to phase out their "free" unshielded light fixtures that plague Southern Utah -- we've finally got an "ally" on their board of directors. To that end I'm endeavoring the make this the biggest media event since the Olympic Torch came through - inviting Congressman Jim Matheson, our Regional Chief of Interpretation, Phil Zichtermann, perhaps the director of the entire NPS, Mary Bomar, all the major television stations, etc. Needless to say we would forever be in SLAS's debt if we could count on a strong showing from your always excellent club members for that Wednesday night! Of course SLAS would be recognized as our guests of honor second only to Story Musgrave! Kevin Poe (435) 834-4412 Interpretive Park Ranger Bryce Canyon National Park

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Re: [Utah-astronomy] Seeking audio podcasts
by Canopus56 23 Apr '08

23 Apr '08

Pamela Gay's Astronomy Cast http://www.astronomycast.com/ BBC Radio-Science http://www.bbc.co.uk/radio4/science/ - Kurt ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

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Re: [Utah-astronomy] Cloudy Nights to Webcast NEAF 2008
by Canopus56 23 Apr '08

23 Apr '08

The Cloudy Nights NEAF webcast interview times have been posted at: http://www.cloudynights.com/item.php?item_id=1782 Note the interview with Al Nagler. CN-MOBILE CAM Saturday, April 26 12:00 PM Interview with NEAF organizer Alan Traino Saturday, April 26 1:00 PM Interview with Scott Horstman of Backyard Observatories. Saturday, April 26 3:00 PM Interview with Mike Bieler of Astronomics / Cloudy Nights. Saturday, April 26 TBA Interview with astronomy authors Phil Harrington and Glen Chaple. Sunday, April 27 9:45 AM Interview with Roland Christen of Astro-Physics. Sunday, April 27 3:00 PM Interview with Al and David Nagler of Tele Vue. - Kurt ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ

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