Are you interested in Astronomy? Do the stars in the night sky fascinate you? If
so, then you need a telescope.
A telescope is a device that allows you to see things that are very far away
from you, such as the moon, the planets, stars, nebulas and galaxies.
A
telescope that you can look through and see images directly is called an optical
telescope. Owning a telescope literally opens up the heavens for your
exploration.
There are three basic types of optical telescopes:
- A refracting telescope uses two convex
lenses working as a pair to gather and focus light in a way that makes
distant objects appear much closer than they actually are. This process is
called refraction.
An objective lens is the larger lens on the end of the telescope opposite
the user. This is the lens that gathers light. The eyepiece is the
smaller lens that you actually look through. It focuses the light that
the objective lens gathers.
- A reflecting telescope uses concave
mirrors to "bend" the light together at the focal point. This also
makes far away objects appear closer than they actually are.
A parabolic mirror at the far end of the reflecting telescope focuses the
light at the eyepiece end after it has been deflected by a smaller mirror
located somewhere in the middle of the telescope.
- Schmidt-Cassegrain style telescopes use both mirrors and lenses to
"fold" the path of the light back onto itself. This allows the
telescope to have a large magnification capability yet still be housed in a compact tube.
There are several things to consider when deciding which telescope to buy:
- The most important consideration when choosing a telescope is the aperture.
The larger the aperture the more light the telescope will gather. The more light
gathered the fainter the object that can be seen.
- The least important (and most misunderstood) factor is magnification.
You'll see ads for telescopes boasting a magnification of 200, 500, or whatever.
Take this information with a grain of salt.
A telescope cannot magnify an object
that it cannot see, and a smaller aperture gathers less light which in turn
limits the distance of the objects that can be seen.
- If you are concerned about getting a good value for your money, do not
purchase a telescope from a department store or discount store. Do your shopping
where serious astronomy equipment is sold.
Good deals on quality, really useful
telescopes can be found in scientific retail stores, in ads in the major astronomy
magazines and of course online.
- Don't spend too much money. How much is too much? More than you can really
afford to spend.
- Don't spend to little money. How much is too little? Less than you can
afford to spend, and certainly do not spend less than $300 as a general rule.
The bottom line is this: buy as much telescope (the largest aperture) you can
afford, don't worry about magnification, and buy from a reputable source.
More Interesting Articles |