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Re: [Utah-astronomy] Seeing Formula
by UTAHDEB＠aol.com 03 Nov '03

03 Nov '03

Dale, I was looking through the Appendix E catalog of deep-sky objects and I noticed the contrast index of some of the galaxies I recently observed about two weeks ago. I observed NGC 1073, NGC 247, and IC 1613 in Cetus. They all were a bit difficult in my mag 6.0 skies because of the low contrast index which ranged from 0.2 to -0.5. NGC 1073 and NGC 247 showed better contrast at Jerry Foote's house last Oct 2002 because the darker skies. It seems skies must be dark and transparent for these lower contrast objects to show better detail. High contrast objects such as M77 and NGC 908 showed up well at my Arizona observing location. Anyway, I thought it was an interesting table. Debbie

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RE: [Utah-astronomy] Seeing Formula
by Dale Hooper 03 Nov '03

03 Nov '03

Chuck, Are you referring to the Roger Clark information when you say "usefulness of tables like these."? If so, I'm rather surprised and suspect that you haven't looked at the information very closely. There is a wealth of info in those "tables", other parts of his website and his book. The website and his book present better ways to be prepared for "the hunt" and how to get the most out of observing "the kill". Its a bit of a disservice to pooh pooh this information just because Clark applies the scientific method to observing. If you aren't referring to the Clark info - then my apologies. Also, I didn't really take it that Brent was referring to the Clark info. > -----Original Message----- > From: Chuck Hards [mailto:chuckhards@yahoo.com] > Sent: Monday, November 03, 2003 5:22 PM > To: Utah Astronomy > Subject: Re: [Utah-astronomy] Seeing Formula > > > I side with Brent on the usefulness of tables like > these. What they seem to do mostly is keep people > from even trying to find certain objects. Remember > that you're just reading someone else's successes and > failures. There are too many variables to assign > absolute visibility factors. > > C. > > --- Brent Watson <brentjwatson(a)yahoo.com> wrote: > > > > "...since I have gotten into astronomy I have never > > seen soo many get soo excited over soo little." > > > > To many of us the hunt is as important as the kill. > > Sometimes even more so. > > > __________________________________ > Do you Yahoo!? > Exclusive Video Premiere - Britney Spears > http://launch.yahoo.com/promos/britneyspears/ > > _______________________________________________ > Utah-Astronomy mailing list > Utah-Astronomy(a)mailman.xmission.com > http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > >

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More inexpensive astro binoculars
by Chuck Hards 03 Nov '03

03 Nov '03

In the current Heartland America catalog: 15x70mm Barska Blackhawk "Jumbo" binocular. Appears to be another Bear/Obie/Galileo/Celestron clone, black rubber "armor". Item no. YC-59904 Reg. $69.99 Now: $59.99 Order before 1/31/04 and get a free tabletop tripod. 9x63mm Barska Blackhawk binocular, rubber "armor". For those who's pupils will open to 7mm. Item no. YC-59924 $49.99 www.heartlandamerica.com 1-800-229-2901 Sometimes the on-line stock number has a different prefix than the paper catalog. __________________________________ Do you Yahoo!? Exclusive Video Premiere - Britney Spears http://launch.yahoo.com/promos/britneyspears/

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Re: [Utah-astronomy] Seeing Formula
by Brent Watson 03 Nov '03

03 Nov '03

"...since I have gotten into astronomy I have never seen soo many get soo excited over soo little." To many of us the hunt is as important as the kill. Sometimes even more so. __________________________________ Do you Yahoo!? Exclusive Video Premiere - Britney Spears http://launch.yahoo.com/promos/britneyspears/

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RE: [Utah-astronomy] Seeing Formula
by Dale Hooper 03 Nov '03

03 Nov '03

Jim, I think the following links will go a long way toward helping you with what you are asking about. You should definitely look at his discussion about Optimum Magnified Visual Angle and Appendix E from his book. http://clarkvision.com/visastro/index.html <http://clarkvision.com/visastro/appendix-e.html> http://clarkvision.com/visastro/appendix-e.html Clear skies, Dale. -----Original Message----- From: Dale Hooper Sent: Monday, November 03, 2003 9:22 AM To: Utah Astronomy Subject: RE: [Utah-astronomy] Seeing Formula I could see if there is anything in the book, "Visual Astronomy of the Deep Sky" by Roger N. Clark. -----Original Message----- From: Jim Gibson [mailto:xajax99@yahoo.com] Sent: Saturday, November 01, 2003 4:35 PM To: utah-astronomy(a)mailman.xmission.com Subject: [Utah-astronomy] Seeing Formula To the group's knowledge, has any one run across a formula for determining whether you might be able to see an object or not? I realize that there are factors like how well one sees, what the seeing conditions are, how big and objective one is using etc. If I made a simple little formula like 1/Mag/Object Size and I applied the formula to M51 with Mag 9.6 and size 5.4' that would produce a factor of .019. If I also applied the formula to NGC 4236 with Mag 9.7 and size 18.6' I would get a factor of .0055. I have never been able to see NGC 4236. So is it valid for me (using a 12.5" objective) to say that somewhere between .019 and .0055 is a cutoff as to what I can see? I know this is going to cut some of you wrong, because since I have gotten into astronomy I have never seen soo many get soo excited over soo little. Jim _____ Do you Yahoo!? Exclusive Video Premiere - Britney <http://launch.yahoo.com/video/?1093432&fs=1&redirectURL=http://launch.yahoo…> Spears

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Re: [Utah-astronomy] Seeing Formula
by UTAHDEB＠aol.com 03 Nov '03

03 Nov '03

Jim, This galaxy, NGC 4236 showed up well at Wolf Creek Pass when I observed it in 2002. I like to observe galaxies in mag 6.0 or better skies. This galaxy, along with NGC 247 and NGC 891 are low surface brightness galaxies. Use 100X or lower to see them. They show more contrast and detail in darker skies than in light polluted skies. When I'm out observing on my driveway I don't even bother with galaxies because of the light pollution and the lack of contrast. I don't really go by formulas but by my own experience. I don't even like to use my red flashlight much when observing the faint fuzzies. Hope this helps, Debbie

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RE: [Utah-astronomy] Seeing Formula
by Dale Hooper 03 Nov '03

03 Nov '03

I could see if there is anything in the book, "Visual Astronomy of the Deep Sky" by Roger N. Clark. -----Original Message----- From: Jim Gibson [mailto:xajax99@yahoo.com] Sent: Saturday, November 01, 2003 4:35 PM To: utah-astronomy(a)mailman.xmission.com Subject: [Utah-astronomy] Seeing Formula To the group's knowledge, has any one run across a formula for determining whether you might be able to see an object or not? I realize that there are factors like how well one sees, what the seeing conditions are, how big and objective one is using etc. If I made a simple little formula like 1/Mag/Object Size and I applied the formula to M51 with Mag 9.6 and size 5.4' that would produce a factor of .019. If I also applied the formula to NGC 4236 with Mag 9.7 and size 18.6' I would get a factor of .0055. I have never been able to see NGC 4236. So is it valid for me (using a 12.5" objective) to say that somewhere between .019 and .0055 is a cutoff as to what I can see? I know this is going to cut some of you wrong, because since I have gotten into astronomy I have never seen soo many get soo excited over soo little. Jim _____ Do you Yahoo!? Exclusive Video Premiere - Britney <http://launch.yahoo.com/video/?1093432&fs=1&redirectURL=http://launch.yahoo…> Spears

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Aurorae Gallery
by David L Bennett 31 Oct '03

31 Oct '03

Some amazing shots at: http://science.nasa.gov/spaceweather/aurora/gallery_01oct03.html Especially the last few pages...I'm particularly fond of the purple one on page 5 from Lionel Bernardi of Norway... db

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Fwd: Thursday+Friday spots
by Richard Tenney 31 Oct '03

31 Oct '03

Note: forwarded message attached. __________________________________ Do you Yahoo!? Exclusive Video Premiere - Britney Spears http://launch.yahoo.com/promos/britneyspears/

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RE: [Utah-astronomy] The Elegant Universe
by Dale Hooper 31 Oct '03

31 Oct '03

The first two hours are now available on the web in quicktime and realvideo formats at: http://www.pbs.org/wgbh/nova/elegant/program.html The rebroadcast on KUED was last night at 11pm. :-( But, here is a table with the broadcasts on KBYU Einstein's Dream Nov 5, 8:00PM Einstein's Dream Nov 8, 5:00PM The String's the Thing Nov 12, 8:00PM The String's the Thing Nov 15, 5:00PM The first broadcast of hour three will be Nov 4th at 7pm on KUED. Clear skies, Dale. > -----Original Message----- > From: Joe Bauman [mailto:bau@desnews.com] > Sent: Wednesday, October 29, 2003 12:16 PM > To: Visit http://www.utahastronomy.com for the photo gallery. > Subject: RE: [Utah-astronomy] The Elegant Universe > > > Anybody know when it'll be replayed? I missed taping the first 10 > minutes. -- Thanks, Joe > > _______________________________________________ > Utah-Astronomy mailing list > Utah-Astronomy(a)mailman.xmission.com > http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > >

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