March 2010 - Utah-Astronomy - mailman.xmission.com

New Ealing focuser
by Canopus56 28 Mar '10

28 Mar '10

Patrick wrote: > At least one of those variables has been addressed in that Bruce tells me > the fancy new focuser SLAS purchased for the Ealing has been installed. > So hopefully there's less slop there. Cool, can't wait to see it. - Kurt

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Skywizard reference bright star slews to Messier and Caldwell table
by Canopus56 28 Mar '10

28 Mar '10

This is to announce an update to a list originally issued in March 2008 to support Ealing targeting of Messier and Caldwell objects: Messier Caldwell Bright Reference Star Slews for Skywizard and Ealing http://fisherka.csolutionshosting.net/astronote/plan/mansetcir/html/Messier… Because of its long 5080mm focal length, low TFOV with a 30mm lens (1/3 deg), mirror flop and focuser flop, the Ealing is a difficult scope to accurately target. A 1/3 deg TFOV has only 1/9 of the search area of the Mak finder's 1 deg TFOV and 1/14 of the usual 1 1/4 deg eyepiece TFOV. With a 50mm eyepiece, the Ealing has a 1/2 deg TFOV which has 1/4 the search area of a 1 deg TFOV search area. Higher accuracy targeting of the Ealing can be achieved with the technique of intermediate bright star slewing - a finding technique built into many planetarium programs. The bright star slew reference table listed above aids in this technique. The list includes two tables: First, all Messier and Caldwell objects are listed by ascending catalogue number. The nearest Skywizard bright reference star associated with that DSO target is listed along with the bright reference star's magnitude, Bayer name and Skywizard id number. The second table is sorted by bright reference star number. This table can be used to locate Messier and Caldwell objects associated with a particular bright reference star. So, for example, assume that at a star party, Denebola or Deneb is located within 30 degrees of transit, typically to the east. Using the second table, the Ealing and Skywizard can be centered and resynchronized to a reference star and then a collection of DSOs that correspond to that reference star can be targeted. With intermediate bright star slewing: 1) the nearest reference star to the target DSO is located; 2) the Ealing is slewed to the reference star; 3) the reference star is centered in the eyepiece; 4) the reference star is centered in the Mak finder;* 5) the Skywizard is resynched on the reference star; 6) the target DSO is found in the Skywizard catalogue; 7) using the Skywizard's "Find" function, the Ealing is slewed to the target; 8) when the target reads within 1 deg on the Skywizard's "Find" display, the Mak finder is used to best position the target within the eyepiece's narrow TFOV; and; 9) a "shark" spiral search pattern is used to bring the target within the eyepiece TFOV. This process is repeated whenever a meridian swap is executed with the Ealing or where the telescope's FOV is moved more than 40 degrees on the same side of the meridian. * DSO or bright star targets easily cannot be centered in the Mak due to its mounting. At best, you can put a bright star within a 1/4 degree of the apparent TFOV center. Memorize the position of the reference star _relative to the Mak's telescope body_. Think of the back of the Mak as a clock face, _relative to the Ealing tube frame_ and not to the local horizon system (E,W,N,S, Zenith). After slewing to the target DSO, try to place the DSO in the relatively same position as the bright reference star. This will result the greatest probability that the DSO target will be in or near the edge of the narrow TFOV of the eyepiece. There is good probability that a standard shark spiral standard will locate the DSO in the narrow eyepiece TFOV. My use notes on the Skywizard (MS Powerpoint) http://fisherka.csolutionshosting.net/astronote/Ealing/Skywizard_use_notes_… Orion Manual on the Skywizard 3 (similar in operation to the Ealing Skywizard 1). (A hardcopy of the Skywizard 1 Manual is in the Ealing binder at SPOC). http://content.telescope.com/rsc/img/catalog/product/instructions/inst_0780… Lens Table for the Ealing (MS Excel) http://fisherka.csolutionshosting.net/astronote/Ealing/Ealing%20Lens%20TFOV… Skywizard Stellar Database List http://fisherka.csolutionshosting.net/astronote/Ealing/skywizst.pdf Skywizard DSO Database List http://fisherka.csolutionshosting.net/astronote/Ealing/skywiznst.pdf Skywizard Alignment Star List (Excel; Text) http://fisherka.csolutionshosting.net/astronote/Ealing/Alignstar.xls http://fisherka.csolutionshosting.net/astronote/Ealing/Alignstar.txt Clear Skies - Kurt

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Re: [Utah-astronomy] Sky Quality Meter
by Canopus56 28 Mar '10

28 Mar '10

> Does anyone hear have a sky quality meter? Craig, yes I have used one at SPOC. The 30 deg zenithal hole between May through July runs between 5.2 to 5.8 on moonless nights depending on season and time of night. Based on about 5 readings. That deteroriates significantly as you reduce in altitude to 50 degs and approach the horizon with Tooele, the truck stop and the advertising signs. - Kurt

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Great Project that Some of us may want to try
by Rodger C. Fry 26 Mar '10

26 Mar '10

Check out this link it would be a fun project to pursue: http://www.msnbc.msn.com/id/3032619/vp/36043526#36043526 Thanks Rodger fry

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GOTO slew table - bright stars to Messier Caldwell objects
by Canopus56 26 Mar '10

26 Mar '10

I have revised Messier and Caldwell bright reference star slew tables in a 2008 personal amateur project titled "Manual Setting Circles - Basic Use" to better support GOTO slewing in Meade and Celestron handcontrollers. Manual Setting Circles - Basic Use http://fisherka.csolutionshosting.net/astronote/plan/mansetcir/ManSettingCi… In aid of computerized GOTO small scopes, some of the tables include for bright reference stars, the identification cross-reference numbers to the HD and SAO catalogues. HD (Meade) and SAO (Celestron) handcontrollers typically contain one or both of these stellar catalogues. For GOTO resynching of a hand-controller, the table titled "Messier and Caldwell list slews from bright stars above -38° dec by Messier Caldwell number" is helpful. With this list, the telescope user can slew to the nearest bright star to the object, resynchronize their GOTO controller to that bright star and then slew the few remaining degrees to the faint object. Resynchronization of the hand-controller allows for high-accuracy slewing, in particular, for urban and suburban light polluted skies. Some astronomical planning software, like AstroPlanner, build in intermediate bright star slewing utilities that automate the resynchronization process. Table: Messier and Caldwell list slews from bright stars above -38° dec by Messier Caldwell number http://fisherka.csolutionshosting.net/astronote/plan/mansetcir/html/Messier… Clear Skies - Kurt

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Sky Quality Meter
by Craig Smith 26 Mar '10

26 Mar '10

Does anyone hear have a sky quality meter? I suggested SLAS buy one but never got a response. It would be nice to compile real numbers of the various observing sites around here. Craig

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Spend that retirement fund early
by Chuck Hards 26 Mar '10

26 Mar '10

http://cgi.ebay.com/R-E-Brandt-12-Refractor-Telescope-Lens-in-cell-RARE_W0Q…

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Radio Meteor Obs - first visual to radio association
by Canopus56 25 Mar '10

25 Mar '10

To correct: > The spectrograph shows an approach slope - the doppler shift increases with time. s/b The spectrograph shows an approach slope - the doppler shift decreases with time. - Kurt

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Radio Meteor Obs - first visual to radio association
by Canopus56 25 Mar '10

25 Mar '10

A couple of nights ago I was standing outside with binoculars during the early morning hours and saw a sporadic 0.5 to 1.0 mag meteor. I walked inside to see the meteor trace scrolling off my radio meteor observing station. http://www.slas.us/gallery2/main.php?g2_itemId=3192 This was the first time I was able to associate a visual meteor with a radio trace. Hopefully, more will follow with April's Lyrids shows. The slope of the trace corresponds to the visual observation: the meteor decelerated to the southeast but traveling north. The spectrograph shows an approach slope - the doppler shift increases with time. The duration of the trace (the vertical dashed lines are at 1 minute intervals) appears longer than the quarter to half second of the visual observation. - Kurt

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Tooele Area Webelos Camp Needs Astronomy Volunteers
by Brent Johnson 23 Mar '10

23 Mar '10

On May 7 the Tooele area Webelos scouts are having an overnight campout. During this campout they would like to teach the boys about astronomy. They are in need of help from anyone available. It is anticipated that there will be about 120 scouts. The more telescopes that can be brought the better. Easy targets will likely be the best choice (Saturn, M13 etc.). The Wigwam is located on the south end of Tooele, directions will be sent to each volunteer. The site while being in town is fairly well protected from stray light. Anyone wishing to volunteer is invited to spend the evening at the site for personal viewing after the scouts retire (about 11pm). If you are interested, please feel free to contact Roger Ekins (Camp Director) at 882-9919 or send me an email at mitaccio(a)hotmail.com Thanks in advance for all your help! _________________________________________________________________ The New Busy is not the old busy. Search, chat and e-mail from your inbox. http://www.windowslive.com/campaign/thenewbusy?ocid=PID27925::T:WLMTAGL:ON:…

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