That without forgetting the essential names such as Giovanni Cassini, Christiaan Huygens, Charles Messier, Caroline Herschel, Henrietta Swan Leavitt or Edmond Halley. However, from here we would like to highlight the figure of another astronomer who made essential discoveries and whose talent for making telescopes advanced astronomy throughout Europe. it was william herschelBrother of the aforementioned Caroline Herschel.
Friedrich Wilhelm Herschel was born 1738 in Hanover, Germany, in a Lutheran family. His father was the oboist in the Hanover military band. Herschel’s father after Hanover’s defeat against the French invasion at the Battle of Hustenbach He sent both his sons to England In 1757. Herschel quickly learned English and changed his name to Frederick William Herschel. He trained as a musician and composed several musical compositions, including 24 symphony, He was appointed conductor of the Bath Orchestra in 1780.
Sir William Herschel and Caroline Herschel. Color lithograph by A. Diathe, ca. 1896. Wellcome Library, London.Wellcome Library, London
Herschel’s interests, however, went beyond music, particularly astronomy. began to build your own binoculars After taking lessons from a local mirror maker and taking the help of his brothers for the same. In March 1774, he astronomical diary and recorded his observations of Saturn’s rings and the Great Orion Nebula. Although he did not receive any formal education as an astronomer, he managed to change this branch of science forever.
Herschel used his 16-centimeter aperture, 2-meter focal length telescope to discover these stars. from my garden in bath, He discovered more than 800 double or multiple star systems, and his theoretical and observational work laid the foundation for modern binary star astronomy. Herschel also discovered that these systems were “stellar binary systems”. they orbit under mutual gravitational attraction,
in March 1781, Herschel discovered an object that he first classified as a comet, but after several observations and calculations by Anders Lexell, it was determined to be a planet. Herschel named it the “Georgian Star” after King George III, but it later became known as the “Georgian Star”. “Uranus”, This discovery earned him the Copley Medal and the title of King’s Astronomer. He later discovered two moons of Uranus: titania and oberon,
Herschel systematically discovered between 1782 and 1802 “Deep Sky” Objects With two 6 m focal length telescopes. detected more than 2,400 items Which he himself defined as Niharika. They also discovered two small moons of Saturn: Enceladus and Mimas, which are among the smallest spheroidal bodies in the Solar System. Herschel measured the tilt of the axis of rotation marte and see the seasonal changes in them polar ice caps, His studies of Mars and the Moon led him to propose that these bodies were inhabited, an idea that was quite popular with his contemporaries.
In the seventeenth century, the refracting telescope, which had the problem of chromatic aberration due to the fact that different wavelengths of light did not converge. Herschel tried to solve this problem by combining two lenses, but could not obtain sufficient resolution for distant objects. On the other hand, the reflector telescopeInvented by Isaac Newton, used a concave mirror that prevented chromatic aberration and allowed greater magnification and field of view. During his research to improve his telescopes, Herschel discovered infrared radiation From the heat produced when transmitted through a prism larger than that of red light.
Herschel modified reflecting telescopes to improve the image and designed the so-called Herschelian telescope. To make the larger, more symmetrical mirrors, Herschel had to make them himself, making more than 400 telescope mirror Between 6 and 48 inches in diameter. made and sold at least 60 full binoculars of various sizes, providing him with an additional source of income.
Herschel’s largest and most famous telescope’s reflector was 12 meters long With a primary mirror of 125 cm in diameter, it took five years to build and exceeded the initially calculated budget. it became the telescope greatest scientific instrument of the time and allowed Herschel to discover two new moons of Saturn: Mimas and Enceladus. However, this proved too complex for the telescope to operate and ineffective in showing clear images. Nevertheless, Herschel’s technical innovation took astronomy to an extent unprecedented in his time.
Reference:
- Schaefer, Simon (1981). Uranus and the founding of Herschel’s astronomy. Journal for the History of Astronomy. 12DOI: 10.1177/002182868101200102
- William Herschel | Biography, Education, Telescope & Facts, Encyclopædia Britannica.
