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Coma
by DunnDave＠aol.com 16 Sep '03

16 Sep '03

Does anyone have any expirience with Coma Correctors? My newly completed 16" f/5 has coma. I would appreciate any advise anyone might have on how to deal with coma. The Lumicon and TelVue correctors are several hundred dollars so I don't want to just buy one to experiment. Thanks. Dave

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RE: [Utah-astronomy] Sound waves reported by NASA
by Kim Hyatt 13 Sep '03

13 Sep '03

I didn't notice in NASA's story, but on NPR last night they actually said the note was a B-flat, albeit 57 octaves lower than the B-flat near middle-C. I find NASA's attempts to dumb-down such findings by relating them to our everyday experiences very annoying. Can anyone relate to a "sound" wave that is 50+ octaves lower than the threshold of human hearing? Why not call the phenomenon what it is (as you have all clarified): a pressure wave. "Sound," "acoustics" and such terms make no sense without an observer, in this case an observer with the ability to hear the sound. If a tree falls in the forest and there is no one there to hear it, does the tree exist? Let's see if Mr. Wizard is a conductor...

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Re: [Utah-astronomy] Sound waves reported by NASA
by cyanics＠xmission.com 10 Sep '03

10 Sep '03

Joe, Excellent topic :-) I will throw in my 2-cents. It is a pressure wave, but pressure waves and sound waves are the same phenomena. They both work by compression and rarification of a material. It is also true that most gas clouds are empty space, as you said, but in truth nearly everything is completely empty space (space between atoms, covalent bonds, shared orbitals, etc). The phenomena occurs, because the pressure wave is formed by the actual collision of atoms along the path of propagation. Hence, because of the laws of thermo-dynamics, the impact is propagation is nearly perfect with relation to the speed of impact. If a single hydrogen is a accelerated, and eventually collides with another hydrogen, the resulting acceleration will be nearly perfect to the original velocity. This entire process is how star systems are made. As we all know, everything starts with the large Mag. clouds we watch in the sky each night. As one of these pressure waves passes through the cloud, areas condense, causing an increase in local gravity. Enough of these density pockets occur, then gravity is yet increase further. Eventually, this is the catalyst that creates every star and planet, the gas cloud becomes dense enough and hot enough to pass into proto-star phase, radiating nearly exclusively infrared. So, hopefully this is enough info to answer the quandary. If not, just call on good old Dr. science james (still student at the U with contacts in the Physics department) Another interesting note, on passing, this "sound wave" stuff is the same reason we have spiral arms. The stars in the arm don't move as is thought, instead, the pressure wave eminating from the center of the galaxy, causes a spiral to form from the compression and rarfication on a 100-light-year wide scale. Gotta love the unknown. Cheers, James Helsby Quoting Chuck Hards <chuckhards(a)yahoo.com>: > This should make it easier for Joe to believe that > it's truly a pressure-wave phenomemon. I was merely > speaking off the cuff, not attempting to truly > quantify the interstellar density. Hard to be precise > when at work with my mind wrapped around composites > instead of astro-physics. > > Thanks > > C. > > --- Paul Gettings <gettings(a)mines.utah.edu> wrote: > > On 10-Sep-03 8:25, Chuck Hards wrote: > > > The process is mechanical, the same as sound in > > the > > > human range, even though the individual molecules > > are > > > kilometers apart. You are thinking correctly > > about > > In space, the density of molecules is closer to tens > > to millions per cubic > > meter, not km. In the region of a gas cloud, the > > density would be many > > thousands to millions of particles per cubic meter. > > Only in the deepest > > part of intergalactic space could the density drop > > near the particle/km^3. > > > > Hence, it is not very difficult to propogate a > > pressure wave by mechanical > > interactions. The propogation speed (speed of > > sound) is _very_ low > > compared to a normal atmosphere; very easy to go > > Mach 1! :) > > > > -- > > 101 USES FOR A DEAD MICROPROCESSOR > > (100) Killer velcro > > > > > > _______________________________________________ > > Utah-Astronomy mailing list > > Utah-Astronomy(a)mailman.xmission.com > > > http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > > > __________________________________ > Do you Yahoo!? > Yahoo! SiteBuilder - Free, easy-to-use web site design software > http://sitebuilder.yahoo.com > > _______________________________________________ > Utah-Astronomy mailing list > Utah-Astronomy(a)mailman.xmission.com > http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy >

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Sound waves reported by NASA
by Joe Bauman 10 Sep '03

10 Sep '03

Hi all, I have a question that bothers me a little about this release from NASA: http://science.nasa.gov/headlines/y2003/09sep_blackholesounds.htm?list726251 The argument is that the structures seen by Chandra around a supermassive black hole in the Perseus Cluster are evidence of sound waves booming through the surrounding gas. The sound waves "sweep across hundreds of thousands of light years," the Chandra folks say at: http://chandra.harvard.edu/photo/2003/perseus/more.html. The problem I have is that surely, those hundreds of thousands of light years encompass mostly vacuum. What mechanism could allow an excited gas atom 300 miles away from the next atom to pass along sound? Doesn't it require physical contact? If not, I guess those old Flash Gordon movies were right after all, and we should hear the buzz as those sparkler-driven spaceships cruise the interstellar medium. Thanks, Joe Joe Bauman science & military reporter Deseret News bau(a)desnews.com (801) 237-2169

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Harmon's appreciation star party
by Kim Hyatt 05 Sep '03

05 Sep '03

Thanks to everyone (especially Roger Ockey) who has tried so hard to accommodate a Harmon's appreciation star party on a busy weekend, but... If you've seen the weather forecast it doesn't' look good for tonight. Therefore, Harmon's has already cancelled/postponed the event to allow them to get the word to everyone. I checked both calendars (SLAS and Observatory) and saw nothing scheduled for Friday the 19th, so I told Harmon's we would reschedule for that night. Because of the later date, I suggested that we begin at 8:00 with a slide presentation for anyone interested, followed of course by telescope observing. Harmon's has (finally) told me to expect around 100 persons. The media will no doubt continue to hype the Mars opposition, so that number could easily double. Any help would be appreciated. Please RSVP to me (Kim Hyatt) if you will be available to help. Thanks, again! Roger: If you still plan to do something with the Scouts tonight, please let me know. I would be glad to help. Kim A. Hyatt, AIA SL&A Architects 331 South Rio Grande, Suite 304 Salt Lake City, Utah 84101 Tel: 801.322.5550 x122 Fax: 801.322.5557

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Re: [Utah-astronomy] Star Party at Jerry Foote's September 25,26, and27
by UTAHDEB＠aol.com 04 Sep '03

04 Sep '03

Great. I'll try to stay healthy until then. By the way, I think I need the directions again and Jerry's phone number. Debbie

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Re: [Utah-astronomy] Star Party at Jerry Foote's September 25,26, and 27
by UTAHDEB＠aol.com 04 Sep '03

04 Sep '03

Don, I was planning on going to Jerry Foote's place but will there be a separate area for us visual observers so we keep our dark adaptation? Or is this just a star party for astro-imagers only? Debbie

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RE: [Utah-astronomy] Mars comments
by Kim Hyatt 04 Sep '03

04 Sep '03

Ditto, Wayne. Hope we didn't "hog" the telescope and that you got to view as much as you wished. Sometime later I will share sketches of Mars I made on Sunday night with Dave from near Hanksville. -----Original Message----- From: Wayne Reese [mailto:waynereese@qwest.net] Sent: Wednesday, September 03, 2003 9:35 PM To: 'Visit http://www.utahastronomy.com for the photo gallery.' Subject: RE: [Utah-astronomy] Mars comments I would like thank the group for the great trip to Lowell. Kim and David were very gracious and fun to view with. Seeing was great and I'm sure, but I think I just might have seen Patrick, or someone who looked just like him on Mars. Wayne -----Original Message----- From: utah-astronomy-bounces(a)mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of Richard Tenney Sent: Tuesday, September 02, 2003 4:46 PM To: Visit http://www.utahastronomy.com for the photo gallery. Subject: Re: [Utah-astronomy] Mars comments Aw Brent, you're such a killjoy! Of course you are technically correct, but all the hype adds to the flavor of the moment, and it sure has kindled a lot of interest in the community like hyped events (e.g., comets Halley, Hale-Bopp, Hyakutake, Kohutek, etc.) often do. I've had more people sign up on the UVAA web page in the past couple of weeks than I typically get in a year. Granted, many of these are simply following the hype, and will likely "apostatize from the faith" before long, but also for many of them it's just the first step on the long journey towards true photon addiction! And to tell you the truth, I myself had never made a serious observation of mars prior to this year, out of sheer ignorance. Previously I had always only seen a featureless orange blob swimming in atmospheric soup, always with too low power, etc., not realizing what it takes to get a good image, never believing Mars would ever reveal much detail to amateur scopes. It wasn't until ALCON last summer in fact that I learned otherwise from some of the ALPO attendees that were eagerly and vocally anticipating this year's opposition. So, while true it's mostly all hype, hype can be a good thing! :-) -Rich --- Brent Watson <brentjwatson(a)yahoo.com> wrote: > Are we not making more out of this than there really > is? Certainly, Mars is closer than it has been, but > only by a small amount. We have the chance to see > Mars at a somewhat similar distance roughly every > fifteen years. Of the perihelic oppositions of > Mars, > 23 August 1923, 10 September 1956, and 10 August > 1971 > have all been within 0.3 seconds of arc of this > latest > opposition. This is only 1.2% smaller than the > current opposition! Not much when you talk about > observing visually. The difference between this > opposition and the 1923 opposition requires at least > 4 > significant figures to differentiate. (That is less > than 0.1%, and more like 0.05%) > > The opposition in 2018 will be .386 a.u., and the > opposition in 2035 will be .382 a.u. as compared to > this one at .376 a.u. The angular size will be 24.1 > and 24.5 seconds of arc compared to our 25.1. You > won't see much difference there. > > I enjoy looking at Mars as well as the next guy, but > I > think the emphasis on this being the closest > oposition > in 60,000 years is at best overstatement, and at > worst misleading. http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software http://sitebuilder.yahoo.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy

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Gravel Pit Sunday Night
by Joe Borgione 03 Sep '03

03 Sep '03

A couple of us will be going to the Browns Canyon gravel pit tonight (Sunday Aug 31). I'll get there about sundown; weather permitting it should be good! Joe Borgione jborgion(a)yahoo.com --------------------------------- Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software

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Re: A Question
by Richard Tenney 03 Sep '03

03 Sep '03

Rob, I've found that everyone has their favorites, and finding a consensus might be rather difficult! But I'll weigh in my 2 cents, and let others weigh in as well. On my old 6-inch Dynascope, my favorite and most used eyepiece is an old 20mm Erfle. On the 16-inch, the one that is in the focuser probably 90% of the time is my 22mm Nagler -- I LOVE that eyepiece; worth every penny my wife paid for it! ;-) I also use and enjoy (on the 16) a 35mm Panoptic for wide-field stuff (found a cheap used one), and for higher magnifications 13mm and 8mm TV ploessls, though if I could afford them I would like to own a few more Naglers and/or Radians (I've borrowed the 9mm and 13mm Naglers, old and new, and several of the Radians, and love the way they perform). At Wolf Creek Saturday, I had a chance to look through Lowell's 20-inch obsession, and he swears by his Pentax eyepieces. I confess the view of the Andromeda galaxy trio was most impressive in that 40mm Pentax. But I also remember directly comparing the 22 Panoptic with a 21mm Pentax one night in Hobble Creek with Debbie's 15-inch Obsession, and found the Panoptic view better, in my opinion. Lowell will argue otherwise, and said he sold all of his TV eyepieces when he discovered the Pentax line. Everyone's eyes and preferences are different... Chuck Hards, our resident ATM guru, doesn't favor these "glass sandwiches" so much (though he does like the TV Panoptics, just thinks all of them are way over-priced, which they are!), and has many of the University Optics eyepieces (the whole line of Koenigs for example), and prefers Orthoscopics for high power planetary work ("less glass is better"). (Chuck and Lowell, sorry if I misquoted you...) Don't know if that helps or not, -Rich --- Rob Ratkowski <ratkwski(a)maui.net> wrote: > Hi Rich > > > Has anyone ever asked what an ideal set (FL, brand, > type,??) of > eyepieces would be and why?? I guess I'm asking to > see what you all > use the most and why they are useful. I have TV's > of 55,40,26,21,17 > and 10.5mm, 2.5X Barlow, a Meade 32mm 2" and a > Celestron Ultima 30mm. > Still looking for a 5mm TV Radian ............. > Would this be > called a survey w/ comments?? > > > Aloha > Rob > > > PS What do you use?? Which is your most used EP?? > __________________________________ Do you Yahoo!? Yahoo! SiteBuilder - Free, easy-to-use web site design software http://sitebuilder.yahoo.com

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