Performance of AstroTrac TT320X-AG
Submitted by Roland Roberts on Wed, 2010-07-28 21:43It's been a busy year. I bought this at NEAF back in April and have only just now been able to get out and give it a spin. The new feature, of course, is the autoguiding. With the original TT320, the specifications state a periodic error limit of 5 arcseconds per 5 minutes. As it works out, when using my Borg 45ED lens, the pixels in my Canon 350D are about 5 arcseconds wide. What I've seen is that I can, with great care, get exposures up to 4 minutes long, but some of them invariably show trailing and have to be thrown out.
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Estimating Risks
Submitted by Roland Roberts on Tue, 2010-04-27 10:59The April 24, 2010 issue of Science News has an interesting article entitled "Gambling on Experience" which reports on research into how we (people) guestimate risk in real life. I call it interesting both because it is an interesting social question, but also because of a recent dialogue about the topic of cell phones and brain cancer risk reported in a popular magazine.
Light Pollution in Missouri
Submitted by Roland Roberts on Fri, 2010-02-19 12:30Missouri is my home state. I grew up in what was then a rural area south of St. Louis, in Arnold. Seeing the stars at night was no big deal, and something I took for granted. Arnold can longer be considered rural and in the intervening 40 years has gone through the typical suburban sprawl growth pattern along with major increases in bad night-time lighting. During our family visit last summer (2009), it was apparent that the skies are only slightly better than here in Brooklyn, NY despite the lower population density of Arnold. I'll come back to that in a minute.
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Careers in Physics
Submitted by Roland Roberts on Thu, 2010-02-11 21:32- Roland Roberts's blog
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Sun|trek Educational Site
Submitted by Roland Roberts on Thu, 2010-02-11 21:11The January 2010 issue of Physics Today's web watch section mentioned the Sun|trek web site which contains a number of resource for learning about the Sun and it's effect on the Earth. The material is varied and the comment about being "devoted to teaching schoolchildren" is a bit vague on the age group, but the format includes a large number of images and other materials that make it engaging, certainly for middle school and possibly for older elementary students (depending on the lesson). Of course, some of the material is clearly target
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Bay Ridge Regional Science Lab Proposal
Submitted by Roland Roberts on Wed, 2010-01-27 00:20Tonight I attended a community meeting where the main topic of new business was a presentation by Thomas Greene, formerly a teacher at Fort Hamilton High School here in Bay Ridge and now an adjunct professor at Kingsborough Community College, part of the CUNY system.
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Physics at Home, Science Projects
Submitted by Roland Roberts on Fri, 2010-01-22 11:31- Roland Roberts's blog
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Light Pollution from Digital/Video Billboards
Submitted by Roland Roberts on Wed, 2009-12-23 16:39This has been one of my pet peeves for a while, and my kids can already point out the things I'm going to whine about as we drive along the BQE (Brooklyn-Queens Expressway) coming home from Queens. There are several of these video billboards along the road. I have always found it ironic that there are laws dealing with "distracted driving" when the driver does something to distract himself, but nothing about allowing third-parties to deliberately try to distract the driver. I mean, what else does any billboard do but try to draw attention to itself.
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