HOME

   Star Parties

   Star Party Tips

 

An Introduction to Observing
by Wes Stone

GAZE AT THE STARS, NAKED EYE

Amateur astronomy: Isn't that a hobby devoted to looking at stuff in the sky? After a brief dip into the culture of our hobby, you may start to wonder. The emphasis seems to be on the quality of telescopes, optics, and accessories, and the potential price tag zooms to an astronomical size. And heaven help you if you already have a small, inexpensive telescope. What have you gotten yourself into?

Relax. You have finally found a kindred soul, someone who enjoys looking at the sky, the largest public recreation area anywhere. Despite what you may have heard, there is no entrance fee. You may want to pick up some guidebooks and maps, and perhaps some viewing aids, but you can buy these gradually and come back as often as you want. Besides, you were born with the most important optical equipment you will ever own. That's right, your eyes. With these wonderful devices, you have the ability to see nearly 3 million light years into space. When you start exploring the sky, I advise you to take them along. Regardless of what other gear you have, you can start naked eye.

LEARNING YOUR WAY AROUND

Hello. I'm Wes Stone, Sky Ranger. Like I said before, this is a big place. You could spend a whole lifetime here and still not see everything. It's also easy to get lost. I'm too busy to help every newbie who can't find M31, so I'd appreciate it if you spent some time close to home, familiarizing yourself with the landmarks. Yep, I'm talking about constellations here. A lot of people don't bother to learn them. Sooner or later, though, I know they'll be calling on me to drag them out of a rut. Take my advice and get a couple of pathfinders. The Stars: A New Way to See Them is by H. A. Rey, the guy who wrote the Curious George books. When you learn the constellations with the help of this book, you will never forget them. It's sold through Sky Publishing, but I always checked it out of my school library when I was a kid. You'll also want a helpful little gizmo called a planisphere, to show you which stars are up when.

The sky rewards the patient and persistent watcher. It takes a while to get acquainted with the general order of things. Every day, the stars rise four minutes earlier by our clocks, due to the Earth's motion in its orbit around the Sun. The Moon goes from a sliver in the evening to a Full Moon to a sliver in the morning, all in the period of a month. Planets wander slowly along the ecliptic, their motion evident over a few nights to careful watchers. Occasional meteors dart here and there, and artificial satellites lumber steadily along in their orbits. It's hard to believe that many amateur astronomers pay little mind to these motions.

AN INFESTATION OF FLIES IN THE OINTMENT

I'd like to tell you about some problems we've been having up here. Just as non-native species have taken over many ecosystems on Earth, there is an outside menace infringing on our views of the night sky. I am talking about light pollution, and if you've ever compared a city sky with a rural sky you know its effects. You can't see as many stars in the city, you have a hard time seeing the Milky Way, and the sky background is a washed-out pink, orange, or gray instead of a beautiful black. Light pollution's effects are even worse for amateurs hunting big game through telescopes. Fortunately, if you drive for an hour or two in the right direction you can escape most of the skyglow. Try to do this several times each month around New Moon, when the Moon isn't adding its own natural light pollution to the mix. These excursions will show you the sky as it used to look from just about anywhere.

Sky conditions, including weather and light pollution, will dramatically affect what you see. So will the type of optical aid you're using, if any. But there is one more important factor: experience! You won't see as much when you're first starting out, but don't let this get you down. It also means that every hour spent under the stars is valuable and will eventually lead to you seeing more neat stuff than you ever thought was possible.

THE BIG GAME HUNT: MORE POWER TO THE OBSERVER

When you're ready to move on to viewing with binoculars and/or a telescope, I'd like to refer you to my complete Skytour hypertext. I've got lots of pix and information on all sorts of objects in there. For right now, here's a sampler of what you can see when you combine your observing experience with an optical instrument.

The Moon. The Moon has more detail to offer than any other single object in the night sky. Even 7x binoculars will start to reveal craters, and the view through a telescope is stunning. As the Moon goes through its phases, sunrise and sunset fall on different features, accentuating them with shadow detail. At Full Moon, the shadows disappear, but we can see long straight rays of impact ejecta from large craters like Tycho and Copernicus.


The Planets. Aside from the Moon there is one telescopic sight that is a perpetual winner, and that is the planet Saturn. Small telescopes show a tiny disk circled by a ring, and when I show this to first-time observers they can hardly believe that it's real. As you gain experience and use better instruments, it just gets better. Jupiter, too, stands out in a small telescope. Its disk is crossed by two or more dark cloud belts, and its four brightest moons can also be seen. Venus is brilliant and impressive to the naked eye, but watch it over a period of months in a small telescope and you will see it going though its Moonlike phases. The rest of the planets are tougher nuts to crack. Mars is a dinky red dot most of the time, but every two years we get close to it and have a chance to see vague surface markings. Mercury goes through phases, just like Venus, but stays close to the Sun. Uranus and Neptune are starlike points that require effort just to find, but of course you'll want to see them. Pluto is even fainter, out of reach of small telescopes but another object you'll want to see someday.

The Stars. If you've done your reading, you won't be disappointed when you look at a star through a telescope and it looks like, well, about like it looks to your naked eye. That's the nature of stars. They're just too far away for us to see any detail. Stars are most interesting for the company they keep. One of the most enjoyable experiences is going out to a dark site on a summer night and aiming a pair of binoculars at the Milky Way. It dissolves into a multitude of faint stars and fuzzy patches and dark areas of obscuring dust. Looking more closely at some stars, you may find that they are double. Wondering what those fuzzy patches are? Welcome to the world of deep-sky objects.
Deep-Sky Objects. Some of the fuzzy patches are loose, open star clusters. The Pleiades or Seven Sisters is a very bright, nearby example of an open cluster. Others are tightly packed, spherical globular clusters that can be hard to resolve into stars without a good-sized telescope. Then there are the gaseous nebulae like M42 in Orion's sword. Last, but by far the most rather than the least, there are the galaxies. Under good conditions, you can see the Andromeda Galaxy with your naked eye, and binoculars will reveal many more of these island universes. Some are round, some are elongated, and some are almost edge-on, but in small telescopes structures like spiral arms and dust lanes remain elusive. Develop your observing skills, and you will start to see them. Deep-sky objects are hard-hit by light pollution, becoming unimpressive or invisible in city skies or bright moonlight.

I hope you've enjoyed your first forays into amateur astronomy. May your skies be clear and dark, and may you always find what you're looking for.

Return to top

2016 The Rose City Astronomers  All Rights Reserved