William Herschel stands out in the history of astronomy as a remarkable man.
He was initially a successful musician, but then began to concentrate on his hobby of astronomy.
Over the course of the next fifty years, he become the greatest telescope-maker of his time and quite possibly, the greatest observer ever.
The big achievement he is now most often remembered for, is his discovery of the planet Uranus in 1781.
He did this with his home-made telescope. It was the first ever planet discovered by telescope…
William Herschel said of himself, “I have looked further into space than any human being did before me”.
He also encouraged his sister Caroline Herschel and his son John Herschel, to become successful astronomers.
William Herschel was originally from Hanover in Germany, the son of a musician.
Born in 1738, he found himself in 1757, in the army and fighting the French, after they had invaded Hanover.
He deserted and escaped to England.
He began to work as a musician and in 1766, was appointed to a prestigious position as organist at the Octagon Chapel at Bath.
At this time, Bath was a very fashionable resort for high society. William’s Hanoverian origins were probably an advantage, with George the third as King.
His sister Caroline joined him as housekeeper and assistant in 1772 and it was from his house in King Street, Bath that he began to practise astronomy.
He began to make his own telescopes, being dissatisfied by those that were available at the time.
Herschel made reflecting telescopes, using a mirror to gather light, instead of the more usual lens. He made his own mirrors from a very hard alloy of copper and tin called “speculum”. He somehow worked out a way of polishing the hard surface into a reflecting surface of the correct profile to give a good image.
Two things resulted from the telescope making expertise he had developed. Firstly, Herschel was able to observe and map the sky in unprecendented detail. Secondly, his telescopes became sought after and Herschel went on to make a lot of money from the building of telescopes.
Caroline played an important part in this work. She was closely involved in the telescope making and also the observation work.
His big breakthrough came in 1781 when he discovered Uranus. He became famous and was summoned to visit King George III, to demonstrate his telescope and explain the discovery.
As a result, the King appointed Herschel as his own astronomer, with a salary for himself and his sister Caroline, plus a house at Slough (near Windsor) which was to be set up as an observatory.
He also pardoned him for desertion from the army.
There at Slough, William built his largest telescope which had a 48 inch mirror and a focal length of 40 feet.
For more than thirty years, the Herschels continued with their meticulous work on the night sky.
They sent countless papers to the Royal Society, cataloguing and describing the objects they had observed.