November 2006 - Utah-Astronomy - mailman.xmission.com

test
by Kim 15 Nov '06

15 Nov '06

Sorry, folks, but I've sent a couple of emails recently that seem to have become lost in the ether. This is just a test to see if this makes it through the gauntlet of electrons. Kim

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Re: [Utah-astronomy] Finderscope poll
by Olhomorto＠aol.com 15 Nov '06

15 Nov '06

I use a Telrad and an Orion 9X50 right-angle correct-view. I thought the Telrad alone made finding objects a breeze. After adding the 9X50 to my routine, I found I could locate obscure NGC objects so much more quickly. Additionally, I find that sometimes I enjoy simply examining the details of the 9X50 view for its own sake, rather than merely utilizing it as a step toward the goal of locating a particular object. I also think the relatively low amount of money I spent on these two tools was more than worth it value-wise for the added enjoyment. Mike Bailey

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Re: [Utah-astronomy] Finderscope poll
by Michael Carnes 15 Nov '06

15 Nov '06

Hiya Chuck, On my main scope (10" dob), I have two finders: Telrad: quick and easy. Gets me to most things immediately. Antares 8x50 right-angle correct-view: If it's trickier to locate, I use this for starhopping. Although some people seem to deal easily with the image inversion between start chart and finder, I don't. With a correct-image finder, what I see in the finder is what I see on my charts. One additional thing that's worth pointing out. My star atlas is the SkyAtlas 2000. If memory serves me, that atlas goes down to mag 8.5. The 8x50 finder is pretty close to that (well, a mag better). That's helpful in matching the map image to the finder image. If I were to go to a deeper atlas such as Uranometria, I might find a 100mm finder was a better choice. The reticle is not illuminated in my finder. Doesn't feel like a loss to me. MC

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RE: [Utah-astronomy] Finderscope poll
by David Dunn 15 Nov '06

15 Nov '06

I only use reflex finders. I have used three different brands. I like Telrad the best. You can see it, to align it with the scope, much earlier in the evening. I also like the Rigel Quickfinder. Both of these are high enough that you can lay your face near the tube of the scope and still use either eye to view through the finder. The Orion is too low and the older versions are difficult to align. The only reasons I see for having a magnifying finder is 1. You need more weight at the end of the tube. (really rare) 2. Star Hopping. I just change the eyepiece to a lower power when I am doing #2. I think that part of my problem with finders was that they added so many stars to the field that I was unable to compare the field to the map (Orion) that I was using. The first one that I had was a 90deg one so the image would have been left and right reversed (if I remember right). That was also confusing. Dave -----Original Message----- From: utah-astronomy-bounces+david.dunn=albertsons.com(a)mailman.xmission.com [mailto:utah-astronomy-bounces+david.dunn=albertsons.com@mailman.xmissio n.com] On Behalf Of Chuck Hards Sent: Wednesday, November 15, 2006 7:35 AM To: Utah-Astro Subject: [Utah-astronomy] Finderscope poll As I begin to address the details on a new scope, I find myself curious as to what the current trends are as far as finderscopes. I have my own personal favorites, but it never hurts to see what else is out there. Can list members help? A. What is the aperture of your primary finder? B. Do you use an auxilliary scope? (larger than primary finder, usually much smaller than main instrument) If so, what is it's aperture? I'm not referring to guidescopes used in imaging applications, but a visual auxilliary telescope mounted on the main instrument. C. Do you use a reflex site? (Terad, Starbeam, Quickfinder, Mars-eye, etc.) D. Is your primary finder correct imaging, inverted, or mirror-reversed? E. Finally, what kind of reticle or other cross-hairs do you favor for the finder, if you do? Illuminated? Just an informal poll. TIA. ________________________________________________________________________ ____________ The all-new Yahoo! Mail beta Fire up a more powerful email and get things done faster. http://new.mail.yahoo.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com

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Back to astronomy (2006 Leonids)
by Canopus56 14 Nov '06

14 Nov '06

Here's a workup I did on this year's Leonid forecast for Saturday night for another newsgroup. Additionally, on Saturday morning at 6:45 am, Mercury will make its brightest appearance of the year in the east/southeast sky. ==================== The S&T calendar states that for this year's Leonids: "Elsewhere on the continent [other than the east coast of the United States], zero Leonids will be visible no matter what the shower is doing at the time." http://skytonight.com:80/observing/ataglance At 4:45 UTC 11/19/2006 (about 1:45am EST), there is predicated maximal outburst with the radiant in the "head" of Leo between eps Leo and eta Leo. The best viewing position at the time of the predicted outburst is in Europe. See Visibility Map at http://www.arm.ac.uk/leonid/index.html . The predicted zenithal hourly rate for the 2006 Leonids is between 10 and 150+? with a high degree of uncertainty. This is a _zenithal_ limiting magnitude estimate. When the radiant is low on the horizon, you see a much lower rate per hour, but a better potential exists to see horizontal grazers - bright bolides streaking horizontally across the sky. >From Salt Lake, eps Leo and the radiant will just be rising over the horizon in the East. The ZHR time prediction is just that, a maximum peak around which a broader shower period will occur. There is a higher degree of uncertainty about the nature and extent of this year's Leonids. Meteor showers occur when the Earth passes through the tracks of a comet - in this case a passage of Comet 55P/Tempel-Tuttle that occured in 1932. There are several of these historical paths - each of which generates a unique cloud of particulars that disperse over time. See Map of Leoniod stream cloud particles at the IMCE: http://www.imcce.fr/en/ephemerides/phenomenes/meteor/DATABASE/Leonids/2006/ - and at Dan Asher's site: http://www.arm.ac.uk/leonid/dust2006.html Cloud-stream interception is predicted to be very well placed for this year, but because the particles were initially deposited from Comet 55P/Tempel-Tuttle in 1932, most of the heavy particles are believed to have dispersed. The initial McNaught & Asher (1999) prediction was that this would potentially be a very good year for a Leonid shower. Follow-up analysis by Vaubaillon et al. (2005a) (see the IMCEE website above) indicated that the small nature of the particles might result in a shower with a high number of particles, but which are very small in size such that most will only be visible telescopically and will not be visible to the naked eye. As Asher's website notes, "Meteors in the outburst are expected to be quite faint, as in 1969; this makes it even more important than usual to be well away from artificial light pollution." http://www.arm.ac.uk/leonid/2006/info2006.html More recently, well-known meteor shower forecasters Esko Lyytinen and Tom van Flandern have confirmed McNaught & Asher's initial time prediction for a peak around 4:45 UTC. See the IMO fall 2006 calendar for a further description. http://www.imo.net/calendar/2006/fall But because a two-revolution old stream can degrade in unexpected ways, the IMO is recommending that since "other possible maxima are not excluded . . . , and observers should be watching as often as conditions allow throughout the shower, in case something unexpected happens." The thinking that the particles in this year's Leonids will be smaller in size and the fact that Leo will be even lower above the horizon at 4:45 UTC in the midwest United States is probably the basis of S&T's statement that "[e]lsewhere on the continent [other than the east coast of the United States], zero Leonids will be visible . . ." Because of the uncertainty and nature of this year's Leonids, you might want to consider telescopic observing and, if possible, using a web cam to record observations of the center of the radiant field near RA 153degs and Dec +22. Further details on telescopic and photographic observing can be found at the IMO Website at http://www.imo.net/photo and http://www.imo.net/tele . In short, the Nov. 2006 Leonids are not expected to be a great year, but are probably still worth a look-see in the early morning hours to check for any unexpected activity. - Kurt ____________________________________________________________________________________ Cheap talk? Check out Yahoo! Messenger's low PC-to-Phone call rates. http://voice.yahoo.com

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Back to astronomy (transit movies)
by Patrick Wiggins 14 Nov '06

14 Nov '06

This will be in Friday's News but I figured my fellow astro-nerds might want to see these now. Here are 4 short MPGs showing all 4 contacts of last week's transit. They were shot by a guy in California. Each one is about 2.8 MB. Note the black drop effect is visible in M2 and M3. www.poyntsource.com/Mercury_Transit/M1.mpg www.poyntsource.com/Mercury_Transit/M2.mpg www.poyntsource.com/Mercury_Transit/M3.mpg www.poyntsource.com/Mercury_Transit/M4.mpg pw

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WARNING: THOSE BORED WITH SUBJECT, don't read: RE:[Utah-astronomy] Climate chaos?
by Tyler Allred 14 Nov '06

14 Nov '06

Joe, I too appreciate the discussion.... but this could go on forever. I think this thread needs to end before we drive away more list members! :) I think I will concentrate on astrophotography and leave this issue for the experts. I will stay as informed as possible, and will voice my opinions with my votes. Cheers, Tyler ___________________________________________

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Dueling experts in the CO2 hockey puck debate (long)
by Canopus56 13 Nov '06

13 Nov '06

For background reading, here is a recap of major studies in the debate concerning whether proxies for temperatures - tree rings, glaciers, etc. - are sufficient to accurately detect climate change. For those of you who follow the news, you'll probably have a hazy recollection of media reports that correspond to these studies - Mann 1999 (MBH1999), based on proxies like tree rings used in the absence of long-term historical temperature records, suggested that the recent rising levels of atmospheric CO2 were associated with rising global temperatures, with the proviso that "we focus not just on the reconstructions, but on the uncertainties therein, and important caveats." In 2004, Mann (MBH2004) published data corrections. Mann was most quoted in the media regarding the claim that the 1990s were the hottest decade in the last 1000 years. von Storch (2004) concluded that the prior assumptions about the relationship between temperature proxies and past temperatures was flawed and may be off by a factor of two. McIntyre (2005) pointed out that if randomn noise is entered in the model that Mann used, a hockey puck pattern is always produced. See Kerr (2005) for a science news summary of the dispute. Several reports have addressed the ongoing expert disagreement on whether proxies are sufficient to detect climate change and to distinguish bewteen human induced and natural variations. IDAG (2004) reviewed their prior findings in light of recent criticisms on whether proxies are sufficiently accurate to detect climate change and concluded that: "These observed climate changes are very unlikely to be due only to natural internal climate variability, and they are consistent with the responses to anthropogenic and natural external forcing of the climate system that are simulated with climate models. The evidence indicates that natural drivers such as solar variability and volcanic activity are at most partially responsible for the large-scale temperature changes observed over the past century, and that a large fraction of the warming over the last 50 years can be attributed to greenhouse gas increases." Id. (Abstract). and that - "Additional uncertainties, such as the effect of differences in model fingerprints and simulations have meanwhile been addressed. It has been demonstrated that averaging fingerprints from multiple models increases our confidence in detecting anthropogenic climate change and that different implementations of the optimal detection method show consistent results. New detection studies show that anthropogenic climate change is detectable in the surface temperature records of individual continents and that it can be distinguished from climate change due to natural forcing." Id. at 24. The U.S. House Committee on Energy and Commerce and the House Subcommittee on Oversight and Investigations requested a scientific ad hoc committee of statisticians to review "whether or not the criticisms of Mann et al. are valid and if so, what are the implications. To this end, Committee staff asked for advice as to the validity of the complaints of McIntyre and McKitrick [MM] and related implications." Ad Hoc Committee Report on the "Hockey Stick" Global Climate Reconstruction, a.k.a. the Wegman Report (2005). Wegman (2005) validated MyIntyre's criticisms that Mann's methods were statistically flawed as to claims that the 1990s was the hottest decade in the last 1000 years: "Our committee believes that the assessments that the decade of the 1990s was the hottest decade in a millennium and that 1998 was the hottest year in a millennium cannot be supported by the MBH98/99 analysis." Id. at 49. "In general, we find the criticisms by MM03, MM05a and MM05b [McIntyre and McKitrick] to be valid and their arguments to be compelling." Id. at 48. The Ad Hoc Committee went further and described Mann and others as politically motivated: "Based on the literature we have reviewed, there is no overarching consensus on MBH98/99. As analyzed in our social network, there is a tightly knit group ofindividuals who passionately believe in their thesis. However, our perception is that this group has a self-reinforcing feedback mechanism and, moreover, the work has been sufficiently politicized that they can hardly reassess their public positions without losing credibility." Id. at 65. However critical the statisticans in the Ad Hoc Committee Report were of Mann, both professionally and personally, in Appendix "B" to the Wegman Report, Committee went on to emphasize that global warming, in their opinion, a fact. The Ad Hoc Committee answered various questions posed by the House, and stated that: "There is strong evidence from the instrumented temperature record that temperatures are rising since 1850 and that global warming is a fact. How accurate the reconstructions over the past millennium are is a matter of debate and we do not believe there is a consensus on this issue." Id. at 65. "Our perception is that principal components (statistical) analysis was used incorrectly and, based on this, unsupportable inferences were drawn about the current magnitude of global warming relative to the historical past. We hasten to repeat that the Earth is getting warmer. What does not appear to be true is that the process mechanism is as well understood as some scholars would have us believe." Id. at 66. "In a real sense the paleoclimate results of MBH98/99 are essentially irrelevant to the consensus on climate change. The instrumented temperature record since 1850 clearly indicates an increase in temperature. Whethe this is unprecedented in the last millennium seems less clear and to what extent the natural planetary processes can mitigate the excess green-house gas release is unknown." Id. at 66. National Research Council of the National Academy of Sciences (2006) undertook a study of the debate pursuant to a request by Committee on Science, U.S. House of Representatives. The NRC was asked "asked to describe and assess the state of scientific efforts to reconstruct surface temperature records for the Earth over approximately the last 2,000 years." The NRC's conclusions were: 1) The instrumentally measured warming of about 0.6 deg C during the 20th century is also reflected in numerous proxies like glaciers and can be simulated with climate models. 2) Large-scale surface temperature reconstructions yield a generally consistent picture of temperature trends during the preceding 1000 years. 3) "It can be said with a high level of confidence that global mean surface temperature was higher during the last few decades of the 20th century than during any comparable period during the preceding four centuries." 4) "Less confidence can be placed in large-scale surface temperature reconstructions for the period from A.D. 900 to 1600. Presently available proxy evidence indicates that temperatures at many, but not all, individual locations were higher during the past 25 years than during any period of comparable length since A.D. 900." 5) "Very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900 because of sparse data coverage and because the uncertainties associated with proxy data and the methods used to analyze and combine them are larger than during more recent time periods." The Stern Report (2006) starts from the point that the hockey puck is largely settled or at least irrelevant in light of the temperature record since 1850. The Stern Report asks what are the likely economic, social and human misery effects from various warming scenarios. A summary of the above can be found in the Wikipedia entry on "Temperature record for the last 100 years" and in Box 1.1 of the Stern Report. http://en.wikipedia.org/wiki/Temperature_record_of_the_past_1000_years - Kurt International Ad Hoc Detection group (IDAG). 2005. Detecting and attributing external influences on the climate system: a review of recent advances, Journal of Climate 18: 1291-1314 http://www.cccma.bc.ec.gc.ca/papers/fzwiers/idag_2004.pdf Kerr, R.A. Feb. 11, 2005. Global Warming: Millennium's Hottest Decade Retains Its Title, for Now. Science 307(5711):828-829 http://www.geo.utexas.edu/courses/387h/PAPERS/Kerr.pdf Mann, M.E., Bradley, R.S. and Hughes, M.K. 1999. 'Northern hemisphere temperatures during the past millennium: inferences, uncertainties, and limitations', Geophysical Research Letters, 26, 759-762 Mann, M.E., Bradley, R.S. and Hughes, M.K. 2004. Corrigendum: Global-scale temperature patterns and climate forcing over the past six centuries. Nature 430, 105 http://www.nature.com/nature/journal/v430/n6995/suppinfo/nature02478.html McIntyre, S. & McKitrick, R. 2005. Hockey sticks, principal components, and spurious significance. Geophysical Research Letters 32:L03710 http://www.climate2003.com/pdfs/2004GL012750.pdf National Research Council. 2006. Surface temperature reconstructions for the past 2,000 years http://www.nap.edu/catalog/11676.html (The report can be downloaded for free, but you have to create a user account.) Stern, N. (H.M. Treasury). Oct. 30, 2006. Stern Review on the Economics of Climate Change. http://www.hm-treasury.gov.uk/independent_reviews/stern_review_economics_cl… von Storch, H., Zorita, E, Jones, J.M. et al. 2004. Reconstructing past climate from noisy data, Science 306: 679-682 http://stephenschneider.stanford.edu/Publications/PDF_Papers/vonStorchEtAl2… Wegman, E.J. et al. 2005. Ad Hoc Committee Report on the "Hockey Stick" Global Climate Reconstruction. http://energycommerce.house.gov/108/home/07142006_Wegman_Report.pdf ____________________________________________________________________________________ Want to start your own business? Learn how on Yahoo! Small Business. http://smallbusiness.yahoo.com/r-index

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Please take my name off
by Jodi Reese 13 Nov '06

13 Nov '06

Please remove me from the emails. Thank you, Jodi Reese --------------------------------- Cheap Talk? Check out Yahoo! Messenger's low PC-to-Phone call rates.

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RE: [Utah-astronomy] Transit pix
by Tyler Allred 13 Nov '06

13 Nov '06

Nice work Rob! Tyler

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