William Herschel (1738- 1822)

Herschel was born in Hanover, Germany, on November 15, 1738, and he died in Slough, England, on August 25, 1822.

To Herschel, music was an important part of his upbringing. Before he left Germany, he was a band boy with the Hanoverian Guards. The next thing he did was, enter the military, where he only served briefly. William thereafter found that his health was too delicate to continue with the military, so he left Germany at age nineteen, in 1757, and went to England, where he took up residence. Later on, he was reunited with his sister, Caroline, and his brother, Alexander, in Bath, England.

After his emigration to England, Herschel continued with his music, and his career really started when he was employed as a military bandmaster, a music teacher, and later an organist at the Octagon Chapel in Bath. He also gave violin concerts, composed military music, symphonies, and choral works. And, he did that by the age of thirty-four.

Herschel also had hobbies. In his spare time, he was devoted to studying philosophy, mathematics, and foreign languages. When he was thirty-five, one of his other interests grew when he read Ferguson's Astronomy, and Smith's Compleat System of Opticks.

After that interest grew, Herschel made it more than a hobby, and supported it with his earnings as a professional musician. He worked with his brother and sister, and they started off by renting small telescopes, but they wanted larger ones. Since, they didn't have very much money, William taught himself to grind mirrors, and to make his own telescopes. William made refracting telescopes like the ones that the professionals of his time had. He created many different size telescopes. He built one with a focal length of five and a half feet. One with a forty-eight-inch reflector, which he built with a four thousand pound grant from King George the third. And, he also made a twenty-foot reflecting telescope, which he made most of his observations with. He also constructed a telescope with a forty-foot focal length. All his telescopes surpassed the size of those of his contemporaries.

William Herschel made many discoveries with his telescopes. One of his most important accomplishments was his systematic survey of the sky. William discovered NGC 2903, a beautiful galaxy, which Charles Messier missed when compiling his catalogue. Patrick Moore also left that galaxy out when he compiled his Caldwell Catalogue, so it was first assigned an extra number by Herschel himself.

Herschel was searching for double stars, expecting that a parallactic shift of the brighter component could be detected relative to the fainter and presumably more distant component. But instead, Herschel actually discovered that one of the starts orbited the other one, which was the first tangible of proof that gravity existed and extended to stars, thus confirming Isaac Newton's theory of gravitation. Because of this work and discovery, William Herschel compiled the Catalogue of Double Stars, the first in its field.

Another one of Herschel's discoveries, which he is probably more famous for, happened on the night of March 13, 1781, when he made the historic discovery of a new planet located in the constellation of Gemini. This discovery got Herschel international fame, and the royal patronage of King George the third. He attempted to name the planet after the king, which earned him the title of "King's astronomer" (but he never became "Astronomer Royal"). After being knighted and awarded an annual stipend by the king, Herschel could devote all his time to astronomy, unhindered by the necessity of earning a living as a professional musician.

Herschel developed some theories on the structure of nebulas and the evolution of stars. He found that some of the "nebulae" were enormous clouds of stars, like our own galaxy. He also published many papers on the evolution of the universe from a hypothetical uniform initial state to one in which stars were clumped into galaxies. This evolution still remains a central problem in cosmology.

Another important discovery was the sun's motion in space. From the proper motions of thirteen stars, William Herschel found that the sun is moving in space relative to its stellar neighbors toward a point located in the constellation Hercules, near the bright star of Vega.

By 1802, William had counted over ninety thousand stars in two thousand four hundred sample areas, and along the way he noted many objects of interest to future astronomers, such as: variable stars, nebulosities, several thousand small nebulous objects or nebulae, and clusters of stars. Some of these categories were in his 1802 Catalogue of Star Clusters and Nebulae.

Herschel concluded from many studies and star counts that the Milky Way System was in the shape of a disk, like a grindstone, and that it had a thickness of about one-sixth of its diameter. He marked the Milky Way by many irregularities, and said that the sun was located near the center, and later discoveries showed that it was in the shape of a disk, but found that it was the sun was not near the center, and that the system was considerably larger than Herschel thought.

William Herschel also discovered the Saturian satellites, Mimas and Enceladus (1789), and the Uranian satellites, Titania and Oberon (1787).

William Herschel was a great musician and a great astronomer. He discovered many things in our universe, and created his own telescopes.