February 2013 - Utah-Astronomy - mailman.xmission.com

Solar Halo
by Dion Davidson 18 Feb '13

18 Feb '13

A coworker pointed out the solar halo visible today. Anyone else see it? This is as good as I could get from my office window in Salt Lake City. https://dl.dropbox.com/u/29767293/halo.JPG Dion

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Large Binocular Project (Was: ATM report)
by Chuck Hards 18 Feb '13

18 Feb '13

It occured to me that a pair of zoom eyepieces could compensate for a focal length difference between objectives that results in a magnifcation difference exceeding the 2% Mil standard. The only drawback is that most zooms have a disappointingly narrow field at low powers. But it would work. A better idea would be a pair of very weak, sliding Barlows ahead of the eyepieces that could be adjusted to compensate for the focal length difference. The focal lengths could then be matched, albeit at a slightly higher primary f-ratio, but you could still use low-power, wide-field eyepieces. And it would only have to be set once. It might take some hunting to find such weak negative achromats of the appropriate diameter. Hmmm... On Mon, Feb 18, 2013 at 2:57 PM, Chuck Hards <chuck.hards(a)gmail.com> wrote: > Thanks Mat. I've had them for a few years, with the idea of building a > giant bino. I have the monster prisms needed for the erecting > systems/interpupilary adjustment as well. I'm hoping that the focal > lengths are close enough to permit the project. > > These are the Surplus Shed 127mm dia x 700mm focal length objectives > in thermoplastic cells. The US Mil standard for magnification differences > between the two halves of a binocular is 2%, above which the stereo effect > is lost. The eye can accommodate for differences below 2%. > > That would mean that with 25mm eyepieces, for example, yielding 28X with a > nominal 700mm focal length, the other objective could be mismatched about > +/- 12mm before we exceed the Mil standard. So it's not as bleak as I > first thought. But something like 5mm mismatch or less would be almost > ideal. The closer the match, the higher I can push the magnification and > stay within the Mil spec. > >

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Dark Matter Identified?
by Chuck Hards 18 Feb '13

18 Feb '13

http://news.yahoo.com/dark-matter-finally-found-big-news-coming-soon-144840…

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Solar Halo
by jcarman6＠q.com 18 Feb '13

18 Feb '13

Sorry, new link http://www.facebook.com/media/set/?set=a.4479284222252.140944.1294436682&ty…

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Re: [Utah-astronomy] New astro drawing
by Kelly Ricks 18 Feb '13

18 Feb '13

Thanks so much Dave. I'm thrilled that you like it:) As for prints, I hope to have something available in the future. I'll keep the group informed. ~Kelly > ------------------------------ > > Message: 3 > Date: Mon, 18 Feb 2013 12:20:35 -1000 > From: Dave Bennett <dlbennett(a)mac.com> > To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> > Subject: Re: [Utah-astronomy] New astro drawing > Message-ID: <4E091CB4-A305-4035-88DA-4051067F27A7(a)mac.com> > Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed > > Incredible work Kelly...love seeing the process too. Where do we buy > prints ;-) > > Dave Bennett > Hilo, Hawai'i > > On Feb 18, 2013, at 11:54 AM, Kelly Ricks wrote: > > > Hello friends, > > > > I just finished another drawing in the astronomy related series > > I've been > > working on for the past few months. You can check it out at my blog if > > you're interested. http://www.kellyricks.blogspot.com/2013/02/ > > accretion.html > > > > Enjoy! > > > > ~Kelly > > _______________________________________________ > > Utah-Astronomy mailing list > > http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > > > > Send messages to the list to > > Utah-Astronomy(a)mailman.xmission.com > > > > The Utah-Astronomy mailing list is not affiliated with any > > astronomy club. > > > > To unsubscribe go to: > > http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > > Then enter your email address in the space provided and click on > > "Unsubscribe or edit options". > > > >

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Re: [Utah-astronomy] Solar Halo
by Brent Watson 18 Feb '13

18 Feb '13

I've been watching it all day. It's not as vivid now as earlier. I've been hoping for more but not seen anything yet. ------------------------------ On Mon, Feb 18, 2013 1:44 PM MST Dion Davidson wrote: >A coworker pointed out the solar halo visible today. Anyone else see it? This is as good as I could get from my office window in Salt Lake City. >https://dl.dropbox.com/u/29767293/halo.JPG > > >Dion >_______________________________________________ >Utah-Astronomy mailing list >http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > >Send messages to the list to >Utah-Astronomy(a)mailman.xmission.com > >The Utah-Astronomy mailing list is not affiliated with any astronomy club. > >To unsubscribe go to: >http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy >Then enter your email address in the space provided and click on "Unsubscribe or edit options".

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Re: [Utah-astronomy] Solar Halo
by Brent Watson 18 Feb '13

18 Feb '13

I've been watching it all day. It's not as vivid now as earlier. I've been hoping for more but not seen anything yet. ------------------------------ On Mon, Feb 18, 2013 1:44 PM MST Dion Davidson wrote: >A coworker pointed out the solar halo visible today. Anyone else see it? This is as good as I could get from my office window in Salt Lake City. >https://dl.dropbox.com/u/29767293/halo.JPG > > >Dion >_______________________________________________ >Utah-Astronomy mailing list >http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy > >Send messages to the list to >Utah-Astronomy(a)mailman.xmission.com > >The Utah-Astronomy mailing list is not affiliated with any astronomy club. > >To unsubscribe go to: >http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy >Then enter your email address in the space provided and click on "Unsubscribe or edit options".

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Solar Halo
by jcarman6＠q.com 18 Feb '13

18 Feb '13

Sweet! Thanks for posting.

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Meteor Damage in Russia
by jcarman6＠q.com 18 Feb '13

18 Feb '13

Larry it took me a few seconds to understand what you posted and then ROFL - Tip o' the hat to you!!!

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Meteorite Rush
by D P Pierce 18 Feb '13

18 Feb '13

http://news.yahoo.com/meteorite-rush-begins-russian-scientists-fragments-11… Deloy

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