Watching the night sky has interested many generations throughout time. The invention of the telescope in 1608 by Hans Lippershey started the development and variation of the different designs, up to what we know today as modern and powerful telescopes. Since Galileo used a telescope for the first time to view the moon and Jupiter, this activity not only hasn´t lost its popularity, but it has attracted new observers as well. No wonder that many people would like to own a telescope. If you are one of those people who have decided to buy a telescope, here are the basics as to how to choose your first telescope:
As a beginner observer, you want a telescope that you can carry easily, with little effort and that can sit steadily on any ground, as well as one which has a high quality optics that could allow you to watch most of the astronomical objects in the solar system (the moon, planets, comets, etc.) and can introduce you to astronomy.
One aspect to consider when acquiring your first telescope is the aperture, another name for the diameter of the objective lens of the telescope, which can be a lens or a mirror. The telescope´s aperture will determine the amount of light your scope is going to be able to gather (the brightness of the image), as well as its resolving power (the sharpness of the image).
There are two primary telescope designs to consider:
A refractor telescope gathers light, when light enters through the objective lens and travels to the eyepiece. The combination of the two lenses (objective and eyepiece lenses) is used to gather light on one point and present a magnified, brighter, and clearer image. These types of telescopes tend to be more expensive, depending on the size of the aperture.
In a reflector telescope, light enters and hits a curved mirror (the objective), which reflects the light onto a second mirror, which then takes the light out and into the eyepiece of the telescope. The image produced is less sharp than that produced by a refractor due to the several reflections that the light has to go through. These types of telescopes tend to be less expensive.
The essentials you´ll be looking for in a telescope are the following:
A steady mounting will allow you to set your telescope firmly on the ground, without the nuisance of the wobble, making the focusing nearly impossible. A tripod will allow you to swing your scope up or down, left or right (alt-azimuth mount) and track objects by just turning one axis (equatorial mount).
High quality optics:
A refracting telescope will offer the highest quality image in a telescope system. Refractors are far less sensitive to temperature changes and tube currents than are reflectors. The resulting brightness of image makes the refractor ideal for lunar, planetary and double star observation. Since a reflector telescope uses a secondary mirror, the obstruction of the light path reduces the brightness of the image.
Price of the telescope:
Don´t buy your telescope in a department store where there is a big chance of not finding specialized personnel who can guide you through the process of choosing your first telescope, and always compare the prices. Not all the more expensive telescopes are the best, and you can always find a good starter telescope for a lower price.
There are some good starter telescopes starting from $200 but you can also find some good ones for under $100 and even less. With the vast offer of telescopes out there, this is the right time to become an amateur astronomer.