Pluto is easy to overlook. It doesn't show a disk. You can't see rings, polar caps or cloud features. It's not much to look at. But just seeing the Solar System's most distant planet is a challenge worth the effort.
|Pluto: Finder Chart (May 21 through November 5, 2004)|
The above finder chart shows Pluto's journey through Serpens from late May through early November 2004. The chart is oriented with north up and east to the left to match a naked eye view of the sky. The chart covers roughly an 7° by 5° area and the faintest stars simmer near 9th magnitude. Pluto's motion is plotted at weekly intervals for 0 hours UT beginning May 21 and running through November 5.
Pluto is moving westward toward the Serpens-Ophiuchus border throughout the summer. 4.3 magnitude Nu (53) Serpentis shines about 1.5-degrees to the north until Pluto makes the turn south in late August. Then for a few weeks, tiny Pluto resides within far eastern Ophiuchus. 2.4 magnitude Sabik, Eta Ophiuchi, blazes 2.0-degrees to the southwest. By the end of October, Pluto has re-entered Serpens and is drifting lazily to the east some 2-degrees south of 53 Ser.
The other nearby bright star is Xi (55) Serpentis, a 3.5 magnitude sparkler located 4-degrees east-southeast of Pluto. A couple of nearby planetary nebulae are also plotted.
The area mapped below is for use at the eyepiece of your telescope.
|Pluto: Telescope Chart (May 21 through November 5, 2004)|
This chart shows Pluto's path through Serpens in more detail. Oriented with north up and east to the left, this chart covers a 1.5° by 1.5° area and should prove useful at the eyepiece of your telescope. Pluto's motion is plotted for May 21, 2004 through November 5, 2004. The open squares mark Pluto's position at seven-day intervals.
The chart shows stars to 16th magnitude with larger black circles representing brighter stars. Visual magnitudes are given for several stars. The decimals have been omitted to avoid confusion with stars. Notice the 9.5 magnitude star to the southwest of Pluto's position on May 28.
I recommend you begin your search for Pluto at the bright star, Sabik, indicated in the above finder chart. Also locate the nearby bright stars, 53 and 55 Serpentis. After positively identifying the field, slip in an eyepiece producing a 1-mm exit pupil or about 25X per inch of aperture. This high magnification will darken the sky background and make faint Pluto easier to detect. It will also narrow your field of view considerably, so take the time to determine how much of the telescope chart you're seeing at that magnification.
There are two ways to visually confirm an observation of Pluto. Both involve sketching the field you're observing. Begin by drawing all the stars you see in the high magnification field. Be especially careful to position them accurately with respect to each other. If you have access to star charting software that includes the GSC, you can compare you sketch to a printout of that field. Pluto should be the faint stellar-appearing object not plotted on the printout.
To improve the certainty of the observation, re-draw the same field one or two nights later. Compare the two drawings to find the object which has moved from the first observation to the second. That's Pluto. A comparison of your drawings against a printout showing Pluto's motion should provide final confirmation of the observation.
At magnitude 13.9, Pluto is a challenging target for the novice observer. Under a pristine sky, the most distant of Sol's major planets is just barely perceptible to the most capable observer using a quality 3-inch refractor. Less experienced observers will want to use something with more horsepower. An 8-inch should do the job under dark country skies. Good hunting!
Layout, design & revisions © W. D. Ferris
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Revised: May 21, 2004 [WDF]