Derek Wong wrote:
> I need some help to back up an observation I made of Pluto at
> approximately 12:30-1 AM PST on 5/28/00 at RTMC (7600') with a 92mm
> refractor. Seeing was good in this aperture and the magnifications
> used (112x, 150x). Limiting magnitude was better than 6, but there
> was some light pollution present. I had to use some controlled
> hyperventilation to help me out, and was seated, well hydrated,
> comfortable and kept my observing eye covered. Pluto was visible
> about 30% of the time.
>
> I have been "heavily questioned" on another list because to many
> Pluto appeared dim in an 18".


Derek, don't be too bothered by being "questioned" by others who are
doubters; just give them the answer: you very probably saw it. I find
that when I can see Pluto, it is usually not when I am using the lowest
power I have available, and that is at least partially the key (most
people just aren't using enough power). I like 101x to 220x on my ten
inch Newtonian for observing it, although I often need lower powers to
get the correct field in the scope. One evening last year, I found
Pluto in my ten inch and then used my variable aperture stop to stop
things down to around 94mm. I could still just "barely" see Pluto even
at that aperture. I didn't manage it at 80mm, but I can quite easily
believe a 92mm refractor could do it under the proper conditions. Clear
skies to you.
--
David Knisely KA0CZC@...
Prairie Astronomy Club, Inc. http://www.4w.com/pac
Hyde Memorial Observatory, http://www.blackstarpress.com/arin/hyde
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