I remembered today the discussions over the last few years about observing Pluto in smaller scopes. With opposition coming up I decided tonight was my chance.
First I tracked it down in the 32” using Sky Safari 6 with its extended star data base to magnitude 17. It makes locating Pluto pretty quick and easy.
Using that knowledge I put the TOA130 into action. It was easy to get orientated using the brighter asterisms in the field of view that I could see in the 32”. I started off with the 10 Ethos for 100x, and had some early indications of Pluto. I swapped it out for the 6 Delos for 166x and the magnitude 13 field stars I was using popped into strong direct vision. Pluto was quite obvious with averted vision, to the point I could almost hold it with direct vision.
This is my first attempt at Pluto with anything less than 12”, and I was surprised at how easy it was. I did have a very good sky tonight, well above average seeing and transparency for my site, so that certainly helped.
I don’t know what is the smallest aperture used for a successful Pluto observation, but given what I saw tonight, I figure someone with great eyes could probably do it with a 4”.