What is a telescope?
Astronomers utilize a telescope as a device to observe objects in the distance. Most telescopes, and all large telescopes, make use of curved mirrors to accumulate and concentrate light from the night sky. The first telescopes were designed to concentrate light by using curved pieces of transparent glass, otherwise known as lenses. So why do we resort to mirrors nowadays? One reason is that they are lighter and can be made more smoothly, as opposed to lenses.
The reflective surfaces or lenses of a telescope are referred to as “optics”. Highly effective telescopes are capable of detecting even the faintest and most distant of objects. To do so, the optics – either mirrors or lenses – need to be very substantial. The larger the mirrors or lenses, the more light the telescope can collect. The light is then focused by the shape of the optics. It is this light that we observe when we peek into the telescope.
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