I have a 24" f/3.3 For me the coma is not a problem at all with the paracorr. Maybe I'm not very sensitive to it ? ;-) Collimation is sensitive but not...
Thanks for all your replies. I decided to take the leap and signed up with a great optician to make a mirror. Last night I received the latest issue of ATT...
Hello to all! My name is Mike, and I just found this new group and joined up! I uploaded one photo of my 20" f/3.6 to get things going. While not 100% a "Dob"...
This has been bothering me for awhile and I can't find an answer... While doing some naked eye star gazing one night last winter, I noticed that Regulus was...
Almost always, stars will twinkle and planets will not. The simplest reason is because stars are pinpoint light sources, where planets (and satellites) are...
Oh, I was going to add that there have been nights with EXTREMELY TERRIBLE seeing that I've seen planets not so much twinkle, but instead jiggle around a...
Tim, What you observed is because planets and satilites have "size" and stars are one dimential objects. Generaly stars have no size and are only single points...
Thanks for the responses. That is the explanation I've always heard too. And in telescopes, stars are definately point sources with no resolvable disc...
Even if the eye can't resolve them, the planets do have diameter - they don't have a single source point - whereas stars are single points. Bob Bunge...
OK. So, how far out does an object have to be to be considered a point source vs. extended object. Stars are also extended objects with diameter - our sun is...
This seems to beg the point. Stars obviously have much larger diameters than planets. I suppose given the distances they subtend an angle of effectively zero. ...
To be clear, I should have said diameters in arc seconds. I don't know know of any stars other than the Sun that has a measurable diameter as seen from a...
This is probably all academic, but would asteroids twinkle. Or is the combination of their size and distance enough to render them a point source? ... know ...
I suppose it would matter on how big and how far away they are. It would all depend on the seeing as well. Planets can twinkle too if it's bad enough. There...
Planets are large enough to be larger than points of light. Therefore the atmosphere doesn't tend to blur them (twinkle) as much as a point source. The best...
Thanks for all the responses. So, the concensus is that planets don't twinkle because they are close enough (and thus big enough) that there are enough light...
Hi, Does anyone have a spreadsheet listing all NGC objects along with their magnitude, angular size, and type of object? I've found several resources on the...
If you have SkyTools software, you can download one. I have it on my computer. Jack Estes Cell phone 512-657-9062 Home phone 512-418-1790 Austin, TX 78759 ...
Is Sky Tools updated with info from the NGC/IC site? If not, going directly to http://www.ngcic.org/public_HCNGC/HCNGC.htm and downloading the spreadsheet is...
I would highly recommend the Saguaro Astronomy Club's database (version 7.7). http://www.saguaroastro.org/content/downloads.htm [Non-text portions of this...
Thanks to everyone who replied. I now have 3 very good NGC lists on spreadsheets - each is very good. Thanks again! P.S. Why is there no magnitude data on...
Thanks to everyone. I've downloaded the 3 lists suggested and now have 3 very good NGC spreadsheet lists. Thanks! P.S. Why is there no magnitude data on...
Argo Navis has kazillions of Washington double stars but I'll tell you if you look at 'em you're not going to find a whole lot of interest, near as I can see....
Tim, If you're interested, I (in fact a macro that is not anymore in the file) have also added the chart number for each object for Sky atlas 2000, urano...
Raphael, Thanks muchly! I've very much appreciate a copy of your file. You can email it to me at starenergy@.... Thank you so much! Tim ... file) have...
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