Sometimes it's easy, often it's not. Spotting Uranus and Neptune is often tougher than one expects because they wander into regions without readily visible stars. Pluto, always a challenge, is even more challenging when it's in a region of dim stars.

Finding the bright planets Venus, Jupiter, Saturn, and Mars is pretty easy. You just have to remember they're wanderers through the night sky and pay attention to when they'll be visible. Mercury, although relatively bright, is tricky to find because it's elusive, hugging the horizon and only popping up above it every six weeks or so. You know in advance when it'll be visible, but it's hard to clear your calendar so you can get out and see it just at sunset at a spot with a good Western horizon. Oh yeah, it has to be clear, too!

The dim planets Uranus, Neptune, and Pluto are different. They're the slowest wanders through the background stars. In fact, the Earth orbiting the Sun causes most of their apparent motion. Finding these planets differs primarily in degree of difficulty. Uranus is a fairly easy binocular object, Neptune is a good binocular or small scope challenge (3" - 6"), and Pluto is a serious challenge for larger scopes (8"+). If you have enough aperture then the problem breaks into two pieces. The first is knowing where to look. The second is whether the planets are near bright stars or recognizable asterisms.

Finding out where to look is easier than it was just a few years ago. There's now a wealth of software available that can show you exactly where these wanderers are positioned. I use SkyChart 2000 because it's inexpensive, easy to use, and has large enough databases for my purposes.

Of course, you don't have any control over where the planets are located and their positions can change noticeably from night to night. When they get into an area with bright stars or stars in a distinctive pattern you can pick them out with relative ease. However, when one of these wanderers gets into a region devoid of brighter stars, it can be very difficult to identify.

Bright is relative. In my experience the naked-eye limiting magnitude (LM) in a suburban area is about 4.5 and at the club's dark sites it's about 5.5. Objects at the LM are barely detectable in your averted vision. This means that while mag 4.5 stars can be used as "guide stars' to help locate the planets (or any other object) at a dark site, they are of no use when the LM is 4.5. In fact, even mag 4 stars can be difficult to locate in the 'burbs. And, of course, mag 5.5 stars don't help at a dark site.

Uranus and Neptune are currently in Capricorn (Cap) which is a well-known astrological sign, but not a conspicuous astronomical constellation. Uranus is in the horns of the goat and Neptune in the hindquarters. At the western end or tail of the goat are two readily identifiable asterisms. One is the multiple star Alpha Capricorn (Cap) and several binocular fields below it is a delightful triangle formed by Omicron, Pi, and Rho Cap. The rest of Capricorn is impossible to trace in suburban skies and even difficult under darker skies. This makes Uranus in its current position hard to spot. Neptune's position isn't too bad for binocular viewing at a dark site. However, they'll both be easier to spot later this summer and early fall.

Pluto is currently in Ophiuchus (Oph) not far from the magnitude (mag) 2.6 star Zeta Ophiuchus that's above the claws of Scorpius. It's pretty well positioned for spotting.

Uranus

Chart 1 shows Uranus's position in Cap on July 15. The chart has a 10-degree field of view (FOV) with a four-degree circle around Uranus. This is the same FOV I use to show Uranus's position on the NOVAC website charts. I chose this FOV to ensure that there are bright stars in the field. The stars are plotted to magnitude (mag) 7 and labeled to mag 5. As you can see there are no stars near Uranus bright than mag 7 which is why it's hard to identify. This is true during most of the summer! Uranus glows at mag 5.7 while the brightest stars on the chart are Deneb Algedi or Delta Cap (2.9), Gamma Cap (3.7), Iota Cap (4.3), Eta Cap (4.7), and Kappa Cap (4.7).

 Uranus will be much easier to spot in late September and early October when it's nicely positioned near Iota Cap. Chart 2 shows Uranus on October 1. Again, the FOV is ten degrees with a four-degree circle around Uranus and the stars are plotted to mag 7 and labeled to mag 5. You'll probably need to orient yourself with Gamma Cap (4.3) at the far left of the chart then move right to the field with Uranus (mag 5.7) and Iota Cap (4.3). The other stars in the four-degree FOV are 29 Cap (5.3), 30 Cap (5.4), HD202261 (6.0), and (just north of Uranus) HD202890 (6.9). Uranus should be easy to spot from suburban areas with binoculars, and much easier from darker sites where the guide stars are visible to the naked eye.

Spotting Neptune from a suburban location in 10x50 binoculars is difficult. However, at a dark sites it's not too hard. I was able to pick it out of the eastern sky glow at Mickie Gordon a little over two hours after it rose early on June 8.

Neptune's position on June 15 is shown in Chart 3. It's located all by itself midway between two relatively bright stars in Capricorn. The chart has a four-degree field of view with a one-degree circle around Neptune. The stars are plotted to mag 10 and labeled to mag 6. The brightest star on this chart is Rho Cap at mag 4.8, so none of the stars are visible to the naked eye from the suburbs. Rho, Pi (5.3), and Upsilon (5.1) Cap might be visible from a dark site. The labeled stars are visible through binoculars with LM 4.5 skies, although Neptune probably isn't. You will be able to see it through a small scope, but trying to find the Rho, Pi, Omicron triangle has given me trouble. Of course, finding Neptune from a dark site will be easier.

 Neptune will be easier to spot later this summer and into fall as it drifts into the location shown in Chart 4, where it's just below the Omicron, Pi, Rho Cap triangle. Chart 4 shows Neptune's position on August 1 and it has a four-degree FOV with a one-degree circle centered on Neptune (mag 7.8). The stars are plotted to mag 10 and labeled to mag 6. The unlabeled stars in the one-degree circle are HD195298 (8.9), HD195076 (8.6), and HD194809 (9.1).

I spotted Pluto on my second attempt using my 10" f/6 reflector. I'd prepared charts for June 3 at Sky Meadows and thought I'd spotted it. However, it turned out that I hadn't properly set the precision of the charting software so the indicated position of Pluto was off by about 15 arc minutes. I now know it was viewable in my 10" reflector as well as in Mike Mills' 8". It was really frustrating to know it was in the eyepiece but we were looking at the wrong faint little dot. My apologies to the others that were there that night for providing the misleading information.

Chart 5 shows Pluto where Mike, Tim Gleason, and I successfully spotted it at Mickie Gordon (MG) on June 8. The chart has a four-degree FOV with a 30' circle centered on Pluto. The stars are plotted to mag 10 and labeled to mag 8. I'm not very skilled at evaluating transparency, but it wasn't as good at MG as it had been at Sky Meadows several days previously. Averted vision was required to see Pluto and it popped in and out of view. I have no doubt better transparency would have help to see it. And, of course, darker skies would help too. Nonetheless, Pluto is well-positioned near good reference stars this summer. This made a big difference in our ability to know exactly where to look for this elusive target. We started with Zeta Oph, moved to 20 Oph, and then picked up HD151092 (8.5) which is the center star of three that form an easy to recognize "dog-leg" asterism. Seeing Pluto required magnification of over 150x and the FOV in the eyepiece was about 15 minutes of arc. If the field had only included stars mag 12 and dimmer, it would have been nearly impossible to pick out Pluto.

 Pluto will be harder to identify at the end of July and through August. Now look at Chart 6. It won't enable you to identify Pluto, but it shows the planet's location on July 30. This chart also has a four-degree FOV, a 30' circle centered on Pluto, stars plotted to mag 10 and labeled to mag 8. Zeta Ophiuchus is easy to find at magnitude 2.6 and so is 20 Oph at magnitude 4.7. Visible in binoculars are HD150177 (6.3), and HD150382 (6.8), and HD150620 (7.4). Pluto, flickering at a meager magnitude 13.8, is not. Notice that there aren't any "bright" stars in the 30' field around Pluto which will make identifying Pluto difficult. You shouldn't have trouble hopping from Zeta Oph to HD150620 in a low power eyepiece. Then increase magnification and slide to the right. The brightest star within the 30' FOV is 11.5 and there are about a half dozen scattered about similar in magnitude to Pluto. You'll want a chart that plots stars to mag 15 in order to identify Pluto.

 Good Luck!