The grey dot at the end of the pointer is the planet Pluto.

You need not take my word for this. You can refer to the finder chart in the Apr Issue of S&T or download the Palomar image from the DSS http://stdatu.stsci.edu/dss/ and request RA 16 06 00, DEC -07 20 00.

In either case, you will not find a star in the location I have indicated and it is precisely where the finder chart says Pluto should be on this date.

I doubt that I have ever spent so much time and had so much fun achieving something as insignificant as that grey dot. It all started when I received my S&T in March and read the article on finding Pluto. I decided this was a challenge I was up to but with the magic of photography, the probability of success would be greatly increased. I spent hours pouring over charts and DSS images, counting the days (months) till it came into view.

As a training exercise, I started with the same sort of prgram with the asteroid Vesta. A finder chart came out in a later S&T and as Vesta is easily visible in any scope, I could center the photo and guide on what I thought was the asteroid and if it moved a few days later, I had it. You can see the results elsewhere on my web pages.

Pluto presents a greater challenge because all I could see is where it should be and thus far, I have been unable to see the planet visually with my 10" F6 Newt. It also happens to be in a location of very inconspicuous stars and it took several nights with the charts before I found the actual location.

Finally, one night while the moon was still an hour from setting, I took a ten min exposure and found an image where it should be but it was rather lost in the moon fog. I waited till the moon set and got a 20 min exposure just as Pluto was heading for the trees to my west. This is not only a much better picture but also confirms that it was not a piece of dust or some other fluke.

DETAILS

Scope: 10" F6 Newt. Camera: JSP 4x5 Astrocamera. 20 min exposure on Tmax 400 film. Developed for 5 min in Tmax developer.

SEQUEL:

With the moon gone again, I was able to get a much improved photo on July 8. It has moved about 14 arc minutes from the previous photo and to make it easier to find, I kept the easy to spot asterisim from the first photo in the frame but this puts Pluto on the right side of the frame instead of centered.

When comparing the two images, it may seem that the Pluto in the first is also in the second but careful comparison will show that the star near the Pluto position is actually a bit lower and just not visible in the first because of moon fogging.

With this image from the negative fixed in my brain, I spent about an hour, that same night, trying to find Pluto visually but only managed to get two fleeting glimpses, and strangely, only with my left eye. Unfortunately, I did not have the 16" Dob set up so I could not try that. It definitely is a tough see in a 10", at least around here. I can not reconcile the remark with the finder chart about it being a magnitude brighter than the faintest stars plotted. At best, I would call it almost as bright as the faintest stars plotted. .

js

Many things have changed since the above page was written.... a new and larger telescope, CCD imaging and computer aiming of the telescope. It still took two nights to confirm Pluto but the whole project only took a few minutes each night.

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