Friday, March 7, 2008

Sir William Herschel, Astronomer

Friedrich Wilhelm Herschel was born on March 7, 1738 in Hanover, Germany, the son of a German musician. Studying music in the footsteps of his father, he began playing concerts, and by the time he was nineteen, after a brief visit to London, he had relocated there. Shortly thereafter he anglicized his name to Frederick William Herschel, and went by his first name, William.

Over the course of his young adulthood, he became an accomplished musician and teacher. He composed number musical pieces including symphonies and concertos.

As most physicists are aware, the study of music is related to the study of mathematics, with chords and harmonics having mathematical formulations. William began an interest in mathematics and this later lead him to study astronomy. It is in this field, that William made a lasting impact.

After making and using telescopes, William made a key astronomical discovery on March 13, 1781. After first thinking that the small patch of light was a comet, he ultimately concluded, after months of research and calculation, that it was a heretofore unknown planet. This planet is what we now know as Uranus.

Although it was just barely visible to the naked eye under perfect skies, Herschel's use of the telescope had enabled him to become the first person in recorded history to have discovered a planet. All of the other planets known at that time had been observed and identified as planets since antiquity, with their discoverers lost to history. His discovery made him famous.

Just after his discovery of Uranus, he was declared The King's Astronomer and given a royal pension. This allowed him to work full-time on astronomy. He ultimately discovered several astronomical phenomena, including nebulae, which are clouds of dust, gases, and plasma.

William was also a prolific builder of telescopes, which he used for his own purposes and also to sell to other astronomers. The largest telescope that he built, a 48-foot reflector telescope, is perhaps his most well-known. It is shown in the background image of the millennial issue from the Caribbean island nation of Nevis.

The telescope remained the largest ever built for half a century. Even with such a powerful telescope, William actually preferred to use a small one, as it allowed him to move it very quickly, which the large scope did not allow.

William went on to discover several planetary moons, including moons of Saturn and Uranus. He coined the term asteroid as well as identifying over 2500 nebulae during his lifetime.

Based upon his discoveries, he was knighted by George IV in 1816. Just six years later, on August 25, 1822, he died, leaving behind an immense catalog of astronomical discoveries.

Several countries have honored Sir William Herschel on stamps, particularly in 1981, the bicentennial of his discovery of Uranus. One example is from the African nation of Gabon which issued an air mail stamp that year. The background image of the stamp depicts an astronomical theme, while the foreground illustrates Sir William with a three-quarter profile view.

No comments: