Telescope
There are various types of telescopes, the optical telescope is the most
common type. Telescope is a collection of lenses or mirrors that is used to allow
the viewer to see distant objects more clearly. They have common
characteristic that make distant objects appear to be closer.
The first optical telescope was invented by Dutch lens-grinder, Hans
Lippershey, in1608.
The following year, the first astronomical telescope was built by Galileo
from a tube containing two lenses of different focal lengths aligned on a single
axis.
With this telescope and several following versions, lunar mountains Jupiter,
moon, sunspots and the starry were discovered.
Since then, telescopes have increased in size and being improved in image
quality, the systems of computer are used to enhance the design of telescope
so that they become even more complex.