The history of the telescope

Claim that the telescope was not invented some kind of astronomer, optician and lens manufacturer Hans Lippershey. Date of birth of the telescope is called 1608. The news about opening that allows you to look at the sky "naked eye" quickly spread throughout Europe and for the past year, many stargazers from England to Italy collected the telescopic tube, polished the lenses, and watched in fascination at the unusual yet for them the sky.



One of the most famous pioneers "telescopes" was Galileo Galilei. He greatly improved the design of the telescope and in 1610 published a book of his observations of the celestial bodies - "the Starry messenger".

Lens телескопы



All the first models, including Galileo's telescope was a refractor, a telescope with lenses that collected the collected light and magnified the image. The work of all these telescopes is based on the fact that light rays from a very distant object is almost parallel to the moment when they reach the observer.

With a good polishing the exterior lens of the telescope can focus the rays, but if at a small distance from its focus to put a second lens, she will collect the broken outer lens, the rays, thus creating increased several times the image.





External lens called a lens and the second eyepiece. Length of the device depends on the focal length of the lens. When trying to create a good telescope with a small focal length design was truly overwhelming. Another problem of the first refractors were chromatic aberration.

Mirror телескопы



However, the telescope is not necessary to use a lens lenses. The first is to understand Isaac Newton, who in his variant of the reflector used a mirror. It was polished so that the incident parallel rays are collected and reflected back, thus passing in front of a mirror through the focus.



It is clear that with this arrangement of the elements of the observer would obstruct the light to myself and could make observations. Therefore, the telescope was mounted secondary mirror that reflects the focused light into the side hole where the eyepiece.

Reflex телескопы

The above-described Newtonian reflector is the ancestor of various reflector telescopes. This design solved the problem of chromatic aberration, but it turned out to be another type of aberration is spherical. Reflectors are much more compact than refractors, and mirror with a shorter focal length is much easier to manufacture than lenses. Quite popular modern reflector design is the Cassegrain model. The light reflected by the secondary mirror through a hole in the main. This design is very compact, since the eyepiece located directly behind the main mirror.

Today, most telescopes — reflectors, but Amateur astronomers, and small observatories, more likely to use a refractor. Among Amateur astronomers is also popular hybrid catadioptric telescope, which appeared in the 1960-ies, due to the lack of aberrations.published

P. S. And remember, only by changing their consumption — together we change the world! ©

Source: /users/1617

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