Telescopes – Facts, Types, And History

Telescopes are instruments that are used to magnify and view distant objects. Without the use of a telescope, astronomical findings would not have been possible. These, with the help of telescopes, scientists have derived numerous conclusions about celestial objects, even those which are far away in the space.

Silhouette of Two Person Standing during Nighttime
Telescopes – Facts, Types, And History

Galileo’s Use Of Telescopes For Astronomical Discoveries

Scientist Galileo was the first astronomer to use a telescope for the study of celestial objects during the 17th century. Before then, no other scientist had ever used a telescope for astronomy. After he revolutionized the use of a basic telescope for astronomical studies, more powerful optical devices have been invented. Moreover, scientists have also developed complex instruments capable of detecting radiation emitted by the stars, planets, and other celestial bodies.

Furthermore, various types of auxiliary instruments such as the spectrograph, camera, charge-coupled device, and others have also been developed. These have further enhanced the study of space and stars. Various computers, rockets, and spacecraft developed along with the telescopes, aid in the researches. With these devices, scientists have been able to get a clearer picture of the Milky Way and the solar system.

Telescope Pointing at Milky Way Galaxy at Night
Telescopes – Facts, Types, And History

Types of Telescopes – Refractors

Telescopes are of different types but most of them detect electromagnetic radiation. The different types might be using the different phenomenon to detect the radiation. The most common types are refractors and reflectors.

Refracting telescopes are commonly known as Refractors. They are used to study the moon and other celestial bodies in the solar system such as Mars, Jupiter, and a few binary stars. These work on the principle of refraction, when light passes from one source to another. These sources should be of different densities. For example, light refracts when passes from air to glass. A glass lens is used in these refracting devices and also it may have concave, parallel or convex components.

Telescopes – Facts, Types, And History
Telescopes – Facts, Types, And History


Reflectors are the second basic type of telescopes. Furthermore, they use a mirror to collect the light and focus it. Since the celestial objects are very distant, the light comes in parallel form to us. Since they are parallel, the reflector telescope’s mirror directs them to a single focal point. Most modern devices today are reflector types because it has many advantages when compared to refractor devices.

Name Some Famous Telescopes

Keck Observatory, located in Hawaii and built in 1993, these twin devices have advanced adaptive optics. Furthermore, these are adjusted numerous times a second to capture real-time images. Atmospheric disturbances do not cause any impact.

The Hubble Space Telescope, located in NASA, built in 1990, shot to fame by capturing some iconic images such as the deep field, Crab Nebula and Eagle Nebula.

Moreover, the Spitzer Space Telescope, built in 2003 and orbiting in the space, captures infrared rays.

These are some of the most powerful telescopes built by man to study astronomy and also to get more information about stars, space, and other celestial bodies.

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