So you want to buy a telescope for an aspiring young Astronomer and are confused as to what is the best choice. This is a situation that many parents find themselves in. They are blinded by the vast array of types and sizes, some are very basic while others look like the very pinnacle of sophistication.
For a first telescope you will want to keep things very simple and there will primarily be two choices recommended to you. The first of the two telescopes you should consider is known as a Newtonian and is named after the famous English Astronomer and Mathematician Sir Isaac Newton .
The Newtonian is of a type known as a Reflector . It consists of a tube which is open at one end and has a concave mirror at the other. Light from the star enters the open end of the tube and travels down to the mirror, here the light is collected and reflected back up the tube to a small mirror known as the diagonal. This smaller second mirror projects the image at a 90 degree to the side of the tube where the image is picked up by the eyepiece. A 114mm – 4.5″ reflector is a good size of scope for the novice and will give wonderful views of star clusters and nebulae. Most scopes will come supplied with two or three eyepieces, a diagonal and probably a Barlow lens as well . Shop around and get value for money; there are bargains out there to be had.
Your second choice of telescope will be the venerable old refractor . It was with a refractor that Galileo first glimpsed the moons of Jupiter in 1609 . The refractor is an extremely durable design. It is a tube with a lens at one end called the objective; this lens collects the light from the stars and brings them to a focus at the rear of the scope.As in the Newtonian the image is projected into the eyepiece.
A 60mm refractor will prove to be a most excellent instrument for a youngster and is quite simply a brilliant telescope for lunar observation. It will also prove to be a very effective tool for observing variable stars. If you want a scope for life go for a refractor; if you or your child ever upgrade to a larger scope the 60mm can be fastened to it and used as a guide scope .
The final consideration to be taken in hand is which type of mount to choose for your scope. Given that we are talking about a mount for a youngster, the only recommendation I would consider is that of an Alt – Azimuth; this brilliantly simple design is the same as that used in a gun turret.
It can be rotated through 360 degrees and elevated to 90 degrees. The simplicity of its design means that the telescope can be easily handled by kids and adults alike.
The other choice available is the clever Equatorial type . It uses a two axis system for very accurate alignment. These axis are known as right ascension RA and declination DEC. When the declination is aligned with the pole star, the telescope is able to track the motion of the stars across the night sky.
Although the Equatorial design is the most desirable of the two types, it is very difficult to get to grips with; and for a child it will simply get in the way and probably spoil their enjoyment. So my recommendation for your youngster’s first telescope would be a 60 or 70 mm refractor with a focal length of about 700 to 900 mm. It should be mounted on a sturdy aluminium or wooden tripod fitted with a quality alt – azimuth head. It should come with at least two eyepieces, a star diagonal, and a Barlow lens . And remember…Shop around…Bargains to be found!