Key Difference: There are four main types of telescopes. These include The Refracting Telescope, The Reflecting Telescope, Radio Telescopes, and X-ray and Gamma-ray telescopes. Each one works in a different manner.

Telescopes are wondrous technology that allow humans to gaze upon the marvels of the universe. What’s even more surprising is that this technology in not a recent discovery, in fact it is not even from this century. The first telescopes were created in the 17^th century using glass lenses. However, the technology has greatly improved over that time. Today’s telescopes are able to see distant stars and galaxies, the existence of which could not have been even imagined in the 17^th century.

There are currently four main types of telescopes:

The Refracting Telescope or Refractor

The refracting telescope is a type of optical telescope. It allows the astronomer to view the universe by gathering light and focusing it through a lens or a series of lenses to create an image. The lenses make the view larger so that the details may be discerned.  It also make the images brighter by manipulating the light. This the oldest type of telescope, and thus the progenitor that made all subsequent technologies possible.

The Reflecting Telescope or Reflector

Like the refracting telescope, the reflecting telescope is also a type of optical telescope. However, instead of using lenses to depict a picture, it uses mirrors. The telescope itself works quite similar to the refracting telescope, as in it also gathers light and focuses it to form an image. The refracting telescope and the reflecting telescope are the two most common types of telescopes used.

Radio Telescopes

 Radio telescopes, like its name suggests, uses radio waves from distant celestial bodies in order to create an image. Every astronomical body gives off waves, the radio telescopes reads these and deciphers the radio noise into its corresponding radio range of the light spectrum. It then uses the light spectrum to create an image of the star or galaxy. Radio telescopes also differ from the others in the way they look. Unlike the others, radio telescopes have large dish antennas attached to them, in order to be able to catch the radio waves.

X-ray and Gamma-ray telescopes

As their name suggests, x-ray telescopes uses x-rays to create an images, whereas a gamma-ray telescope utilizes gamma rays. However, x-ray telescopes are best used to study suns, stars and supernovas, as they give off plenty of x-rays. Whereas, Gamma ray telescopes detect bursts of gamma rays and help confirm the occurrence of events in outer space like supernovas, pulsars and black holes. Both x-ray and gamma-ray telescopes are best used at higher altitudes so that they can read the rays and create an image, and not worry about earth’s pollution interfering with the rays and distorting the images it would create. Additionally, the atmosphere on higher altitudes is thinner, which also reduces the chances of interference.

In addition to these, there are many more types of telescopes; however, they are quite uncommon. There are also many modified telescopes or telescopes with combined technologies. For example, there is the catadioptric telescope which merges the technologies of the refracting telescope and the reflecting telescope. Hence, it uses both mirrors and lenses to depict images.For example, there is the catadioptric telescope which merges the technologies of the refracting telescope and the reflecting telescope. Hence, it uses both mirrors and lenses to depict images.  

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