08-07-2017, 11:40 AM
A telescope is an optical instrument that helps the observation of remote objects by collecting electromagnetic radiation (such as visible light). The first known practical telescopes were invented in the Netherlands in the early 17th century, using glass lenses. They found use in both terrestrial and astronomy applications.
In a few decades, the reflecting telescope was invented, which used mirrors to collect and focus light. In the 20th century many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. The word telescope now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, And in some cases other types of detectors.
The word telescope was coined in 1611 by the Greek mathematician Giovanni Demisiani for one of the instruments of Galileo Galilei presented at a banquet at the Accademia dei Lincei. In the Starlord, Galileo had used the term perspicillum.
