Re: Splitting Sirius

Dennis Woos wrote:
We split it quite easily a number of years ago with 10" aperture AP
Mak-Cass and a 10" APM Triplet refractor when the separation was only
5 arc sec.
The first poster is right, in general. But I don't disbelieve the second either. Experience, the tenacity to try again and again, and the luck of finding a very steady night can all conspire to make many "impossible" observations possible.

Now if only I could get lucky myself with the pup... One of these nights!


I think you will be waiting a long time if you think that it is only good seeing that makes the difference.

That's a rather presumptuous statement to make, given that I don't see how you know what equipment I have available to me. Gotta love Usenet.

I have spent some time splitting duble/multiple stars in various scopes, and I have found that optical quality is just as important as any other factor. The importance of the fact that both of the scopes cited above are extremely high quality (and extremely expensive) should not be underestimated.

I disagree. While its true that poor optics or poor collimation will make it very difficult to observe the Pup, in my experience there is little to be gained from the additional expense of high end optics (other than to inflate the owners ego). This is particularly true when an expensive small aperture scope is compared to a larger aperture instrument of good quality. It is well known that aperture always wins. And while you may technically be right about seeing in this particular case, the atmosphere still plays a vital role (as I discovered when I successfully observed the moons of Mars, which is a very similar situation).

When it comes to this sort of observation the amount of atmospheric scattering present is the dominant factor, not the size of your wallet.

Clear skies,
Greg

--
Greg Crinklaw
Astronomical Software Developer
Cloudcroft, New Mexico, USA (33N, 106W, 2700m)

SkyTools: http://www.skyhound.com/cs.html
Observing: http://www.skyhound.com/sh/skyhound.html
Comets: http://comets.skyhound.com

To reply take out your eye
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