November 2003 - Utah-Astronomy - mailman.xmission.com

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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