Who is Friedrich Wilhelm Herschel?

Who is Friedrich Wilhelm Herschel?

June 25, 2021 Off By Felso

Friedrich WilhelSir William Herschel, KH, FRS, German: Friedrich Wilhelm Herschel (15 November 1738 – 25 August 1822)

German-born, English astronomer, telescope maker and composer. He was born in Hanover, Germany. He worked with the Hanoverian Military Band until he immigrated to England at the age of nineteen. He became famous for his discovery of Uranus, the 7th planet in the Solar System, the two largest moons of Uranus, Titania and Oberon, and the two moons of Saturn, Enceladus and Mimas, as well as his discovery of infrared radiation and the 24 symphonies he wrote.

Sir William Hershel spent most of his life in England, in a town called Slough (in the County of Berkshire) and died in the same town.

Herschel’s interest in music led him to work on mathematics and lenses. After meeting the British astronomer Nevil Maskeylne, he developed an interest in astronomy and built his own reflecting telescope. In May 1773 he began to monitor and study the sky on a regular basis, and on March 1, 1774 he began keeping an astronomical diary in which he recorded his impressions, including the rings of Saturn and the Great Orion Nebula (M42).

After a while, Herschel turned his attention to examining “double stars” that appear very close in the eye. In 1779, he began to systematically search for “all the stars in the sky” with his Newtonian telescope, 160 millimeters aperture, 2.1 meters focal length, built from the backyard of his home on New King Street in Bath. In his work up to 1792, he discovered many double and multiple star systems, and after careful measurements, he brought these discoveries together and presented two catalogs to the Royal Society of London in 1782 (first catalog of 269 systems) and 1784 (second catalog of 434 systems). In 1821, his third catalog consisting of 145 systems was published, based on his discoveries after 1783. Contrary to the astronomers of his time explaining the movements of the stars (originally advocated by Galileo Galilei), in 1802 he had his own hypothesis; caught in mutual gravitational forces, he put forward the double star systems.

In short, Herchel discovered approximately 800 confirmed binary or multiple star systems. His theoretical studies and observations; It formed the basis of modern binary star observations and evaluations.

In March 1781, while searching for double stars, Herschel stumbled upon a disk that lacked stellar nature. Although Herschel thought that this object was originally a comet or star, the evaluation of Russian Academician Anders Lexell revealed that the orbit of this disk was planetary, and as a result, Herschel concluded that there was a seventh planet beyond the orbit of Saturn. This new planet after King George 3; Although he called it “George’s Star” (Gerogium Sidus), this name did not last. Known as “Herschel” in France, this planet was named after Uranus, the god of the sky with cosmic powers, who was later believed to be both the wife of Gaia and the grandfather of Zeus in Greek mythology. For this discovery, Herschel was awarded the Copley Medal in 1781 and became a member of the Royal Society. In 1782, he was appointed as the King’s astronomer. As a result, in the same year, Herschel settled in Buckinghamshire. In the new city, the astronomer started to manufacture telescopes and sold what he produced to over 60 European astronomers.

deep space exploration

Between 1782 and 1802, Herschel, with his two telescopes (610 cm focal length/30 cm aperture and 610 cm focal length/47 cm aperture), apart from repeated or lost examinations, discovered 2,400 deep space objects, and made these discoveries in three catalogues. published in.

Catalog of One Thousand New Nebulae and Clusters of Stars (1786)
Catalog of a Second Thousand New Nebulae and Clusters of Stars (1789)
Catalog of 500 New Nebulae (1802)

Herschel named the objects in his catalogs as “nebulae” (until Edwin Hubble described nebulae in 1924, large and distorted space objects were defined as nebulae.) and divided the objects into eight “classes”.

Bright Nebula (I)
Weak Nebula (II)
Very Weak Nebula (III)
Planetary Nebula (IV)
Very Large Nebula (V)
Very Compressed and Rich Star Clusters (VI)
Very Compressed Large and Small (Weak and Bright) Star Clusters (VII)
Roughly Scattered Star Clusters (VIII)


During his career, Herschel has produced over 400 telescopes. The telescope, which is the largest and also the most famous, has a 1.26 meter main mirror and a focal length of 12 meters. Since the mirrors of the period could not reflect perfectly, Herschel followed a different path in order to increase the image efficiency and created the model called “Herschelian Telescope” today.