Nautical Gifts Cabin.com
The brass telescope is an instrument that assists in the observation of distant targets by accumulating electromagnetic radiation (such as visible light. The first recognized practical telescopes were invented in the Netherlands at the start of the 17th century, applying glass lenses. They found use in terrestrial applications and astronomy.
Inside a few decades, the reflecting telescope was devised, which used mirrors. In the 20th century a lot of 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 discovering different regions of the electromagnetic spectrum , and in a few cases additional types of detectors.
The word "telescope" (from the Greek t??e, skopein "to look or see"; t??es??p??, teleskopos"far-seeing") was coined in 1611 by the Greek mathematician Giovanni Demisiani for one of Galileo Galilei 's instruments presented at a banquet at the Accademia dei Lincei . In the Starry Messenger Galileo had used the term "perspicillum".
Modern telescopes commonly use CCD instead of film for recording images. This is the sensor in the Kepler spacecraft. The earliest registered working telescopes were the refracting telescopes that appeared in the Netherlands in 1608.
Their development is credited to three individuals: Hans Lippershey and Zacharias Janssen , who were spectacle manufacturers in Middelburg, and Jacob Metius of Alkmaar . Galileo found out about the Dutch telescope in June 1609,assembled his own within a calendar month, and greatly improved upon the design in the following year.
The thought that the objective , or light-gathering element, could be a mirror rather than a lens was being investigated shortly after the invention of the refracting telescope. The possible advantages of using parabolic mirrors -reduction of spherical aberration and no chromatic aberration -led to a lot of proposed designs and a lot of efforts to build reflecting telescopes. In 1668, Isaac Newton built the first practical reflecting telescope, of a design which today bears his name, the Newtonian reflector.
The invention of the achromatic lens in 1733 partially rectified color aberrations present in the simple lens and enabled the construction of shorter, more functional refracting brass telescopes used by mariners .. Reflecting telescopes, though not limited by the color troubles seen in refractors, were hampered by the use of fast tarnishing speculum metal mirrors employed during the 18th and early 19th century-a problem alleviated by the insertion of silver coated glass mirrors in 1857, and aluminized mirrors in 1932.
The maximum physical size limit for refracting telescopes is about 1 meter (40 inches), dictating that the vast majority of large optical researching telescopes built since the turn of the 20th century have been reflectors. The largest reflecting telescopes presently have objectives larger than 10 m (33 feet).
The 20th century also saw the development of the telescope that functioned in a wide range of wavelengths from radio to gamma-rays. The first purpose-made radio telescope entered operation in 1937. Since then, a tremendous variety of complex astronomical instruments have been produced.
The brass telescope is a nautical gift that any mariner will will be proud to own.
Skype ID : derek.allenNauticalGiftsCabin
Nautical Gifts Cabin is going places