G'day Rod
Whew...Pluto huh!? And here was I thinking Mercury had the rather limited appeal in this post.
Well, you have enough aperture to visually detect Pluto from a moderate dark sky location with a 10-inch but its a very, very faint target with a magnitude of around 13.8 and it is difficult to detect among the other surrounding background stars. If you have a GOTO system then you're well under way to narrowing it down in the eyepiece. If you're a star-hopper like me using setting circles then the task of ensuring you have it centred in the correct surrounding star field carries with it a little more uncertainty. A low power eyepiece yielding about 1/2 a degree view is perhaps your the best option and a detailed star chart with low magnitude stars (probably generated with computer software) will allow you to positively identify it.
If you are not intending to take a long exposure photo or image then make a drawing plotting the confusing array of stars in the field. Note also the directions (at least North and East) on the drawing. If you have good software you can work out which one is most likely Pluto by comparing your drawing to the software map. But for true satisfaction of certainty, go out again one or two nights later and compare the view with your drawing (and make another drawing) to see if the star-like Pluto has moved. If so you've done it.
If you have an integrating digital camera you could take two exposes over consecutive nights and do a blink comparison using a image-processing program to detect any wanderers. You will of course need to try your best to orient the camera the same on both nights so that the stars register correctly (or use registar).
Hope this helps.
|