What kind of telescope should I buy?

The biggest consideration (once you've set a price range) is how
'hands-on' do you want the telescope? A Dobsonian style is very simple,
cheap, light and easy to assemble. On the down side, they almost never
have motors. What this means is that the telescope won't track the sky,
so the image will change as the Earth turns. This is a problem if you are
trying to take photographs, but rarely is an issue if you're just using
your eyes. This also means that you'll need to do a little more work
finding your targets if they are faint (planets, the moon, etc usually
aren't an issue, as they are quite obvious).

The next step up in the complicated ladder is a Cassegrain mount with a
plug-in or battery motor. This will counter-act the turning of the Earth,
so if you point the telescope at something, it will still be looking at
that object an hour later (for a Dob, the time in the field of view
depends on the magnification of the eyepiece used, but is around a minute
to a few minutes). You will still need to do your own navigation, and
these tend to be heavier and harder to set up. On the other hand, these
are very useful for astrophotography, if you decide to go that route, as
they provide a stable platform for long exposures.

At the top are the Cass telescopes with computer controls on-board. For
these, once you set up the telescope and point to a few easy targets, all
you need to do is dial into the control pad what you want to look at and
the telescope will swing to it automatically. Schwanky, but again even
heavier and more expensive.

If you don't mind doing the pointing and tracking on your own, a Dob is
probably the best best. The biggest challenge most people face is taking
the telescope out of the closet and setting it up outside, and if it's
light and quick to set up, you'll be more inclined to do so any given
night.

In terms of optics, the most important number is the aperture, or size of
the primary mirror (almost all modern telescopes are reflectors (short and
stubby) instead of refractors which use lenses (long and narrow, like
spyglasses from sailing movies). 6 to 8 inch diameter mirror is plenty
strong enough to get good views of the major planets, comets, the moon,
and most of the Messier objects (these are the primary deep sky objects
most people look at, as they are pretty easy to find, and very pretty).

Messier links:
List of Messier Objects from Wikipedia
Messier thumbnails like what you'll actually see

The magnification of the telesclope is much less important. Most basic
eyepiece sets will provide 2 or 3 different levels of magnification, which
should be quite sufficient. The higher the magnification, the bigger the
object looks, but also the fainter (as it's spreading the light out more)
and the faster it will move out of the field of view. If someone tries to
sell you a telescope on magnification alone, be wary.

Here's a good article on buying a telescope:

Sky & Telescope's advice

(Sky and Telescope is a very reliable source, by the by).

Celestron, Orion, Meade are the most well known makers of quality
telescopes, but there are many other good companies as well.

If you want to look at the moon (which is always a great sight) I'd
recommend getting a basic filter set that includes a neutral density
filter. These should screw into the back of the eyepiece, and will let
you look at the moon without destroying your night vision (the moon is
really really bright, even in a small telescope).


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