Biography of Sir Frederick William Herschel (1738-1822)

German astronomer, born in Hanover (in the current state of Lower Saxony) 15 November 1738 and died in Slough (Great Britain) on 25 August 1822. Considered one of the founders of physical astronomy, contributed many finds to the knowledge of celestial bodies, notably the discovery of the planet Uranus.

His father was a famed musical performer who instilled in him, since childhood, his love of music, which he studied diligently throughout his childhood, combining it with other disciplines that also attracted him mightily, as mathematics, language and philosophy. Paradoxically, he wouldn't be interested in physical astronomy - plot of knowledge which would go down in history - until he had not fulfilled the thirty-five years of age.

His musical talents led him to be part of the guard of Hanover military band, which, in turn, predisposed him to try his luck in the military career. But scarce physical skills to the pursuit of this profession forced him to abandon his martial aspirations to finally focus on the profession of musician, activity in which would also highlight: was a member of several orchestras, concert pianist, music composer and Professor of organ.

This dedication was, precisely, to music which is what prompted him to move to England in full youth, and soon achieved some celebrity as an interpreter to the North of that country, where he was rewarded with the post of organist in the octagonal Chapel of Bath (in the County of Avon). In the exercise of this activity was when, coincidentally, a book entitled fell into their hands Harmonic (harmony), work of Robert Smith, a brilliant Professor of astronomy at the University of Cambridge. Excited by this Treaty, Herschel started to deepen the study of the heavenly bodies, and with the help of another book of Smith, Opticks, came to be built, in 1773, his own telescope, which could soon discover objects not described until then by the traditional astronomy.

The reason which induced him to manufacture their own optical instruments was simply its lack of economic solvency to acquire existing ones. But he immediately warned, implementing with rigour the studies of Smith and other astronomers, he could have a much more powerful and reliable telescopes that they could not buy in the market. Thanks to this determination, Herschel was soon a few devices that enabled him to scrutinize in detail each of the double stars, in search of their respective parallel astros. It was how he discovered that binary stars move one around the other around a common Center. Finally, after having observed the location and movements of more than one thousand of double stars, found himself in a position to write his first astronomy study, titled Catalogue of double stars.

From 1774, Herschel began strongly interested in the nebula of Orión, whose attentive observation claimed one of his first intuitions against the traditional law of Astrophysics: a Nebula was not, as he had come to believe until then, a set of stars whose glare mingled together to acquire the appearance of a unique body, but a gigantic mass of gas. To confirm this hypothesis, was the need to scrutinize Orión and other nebulae a few much more powerful tools which they then had at his disposal, so it fought the construction of a telescope equipped with a three-foot-diameter mirror (something less than a meter); but it failed in the effort to achieve greater range and accuracy, since, for lack of financial means, it could only work with old materials that had been left cornered in the attic of his home.

Limited, therefore, to scrutinize the universe with a telescope of eighteen centimetres of opening, on March 13, 1781 was, with this rudimentary equipment, a discovery that would have the pass to the annals of history. He worked on the measurement of star when he thought the presence of a comet while examining the constellation of Gemini; but looking more closely at this celestial body, warned that the figure of a Comet, had since it had the form of a disk with a perfectly crisp boundaries. Convinced, then, you have discovered a new planet, his intuitions told the Finnish mathematician Anders Lexell, who confirmed his studies with Herschel suspected and officially announced the discovery of the seventh planet of the Solar System.

Delighted with his discovery, astronomer of Hanover baptized this new planet with the name Georgium Sidus ("Jorge Astro"), in homage to King Jorge III (1738-1820), who in turn corresponded to the honor of Herschel - and the importance of his discovery - naming him "Knight of the Court" and "Astronomer of the King"; In addition, the King assigned an annual pension of two hundred pounds, which, from that moment, allowed the German to devote himself to his astronomical studies, without being burdened by economic constraints.

Subsequently, the planet identified by Herschel - which, no doubt, was spotted as a celestial object from ancient times, but without linking it to the rest of the bodies that revolve around the Sun - was baptized with the name of its discoverer; but, at the beginning of the 19th century, the German astronomer Johann Elert Bode (1746-1826) proposed the name of Uranus, that was not widespread until the end of this century.

The enthusiasm of the sovereign Jorge III, the scientists of his Kingdom and the own Herschel was fully justified, since the discovery of the astronomer of Hanover introduced important innovations in Astrophysics as the arrumbamiento of the Platonic solids scheme proposed by Kepler (1571-1630), which only contemplated the possibility that there were six planets that revolve around the Sun.

Favoured, because, by the King and by the pension it had assigned, Herschel was installed in 782 in Datchet, neighboring place to Windsor Castle, where he constructed a gigantic telescope of six meters long (30 feet), equipped with a mirror of 45 centimeters (18 inches). With this powerful tool, it is devoted fully to the search of new nebulae and, assisted by his sister Carolina Lucretia - which had instilled interest by celestial bodies - increased their old catalogue of nebulae in over two thousand units (when, before your casual arrival to the world of astronomy, only it had detected some hundred and fifty).

His contributions to the knowledge of the universe occurred without interruption since it handled as powerful telescope. In 1787 he discovered two satellites of Uranus (Titania and Oberon), and after two years, found other two satellites not identified until then, now belonging to the orbit of Saturn (Mimas and Enceladus). According to his notes, it is possible that in 1801 it also detected the third satellite of Uranus (baptized later as Umbriel), whose existence was not irrefutably confirmed until 1851 by the British astronomer William Lassell (1799-1880).

To these achievements, the Crown awarded him four thousand pounds so he could build the biggest telescope of its time. With this new device, forty feet in length, Herschel made other appreciations of great interest such as the one associated with the mobility of the Solar system within our Galaxy: the German astronomer showed is not fixed and that, in their movement, it moves towards the constellation of Hercules (in reality, the Lira). Based on the movement of thirteen stars as a point of reference, it found that the Sun is moving in space, in relation to its neighboring stars, to a point close to the location of the star Vega, belonging to the constellation of Hercules. In addition, it thoroughly escrutó sunspots and confirmed that the nature of the Sun is gaseous.

Also conceived the ambitious project to describe the structure of the milky way, which devoted more than twenty years of work. At the end of this lengthy period, it had gotten to compute more than ninety thousand star, about two thousand five hundred sample areas; at the same time, this count allowed him to go detecting other many objects in space, such as clusters, nebulas and double stars, variable stars. All these bodies were reported in his magna work Catalogue of Star Clusters and Nebulae (work significantly enlarged, in 1864, by his son John Frederick William Herschel, also renowned astronomer).

But the valuable contributions of Herschel astronomy did not stop here. Also analyzed the different types of nebulae, and set up by white masses, found a huge amount of small stars that revolved in a way regular around which they distinguished as a central star. He also discovered the existence of other galaxies other than the milky way to which baptized as Universos-Islas, and explained that its nebulous appearance is due to the great distance that separates them from the Earth, distance that prevents clearly contemplate its stars one by one with individual and independent bodies.

Author, in addition to the aforementioned Catalogue... an excellent tried to Astrophysics titled Motion of the solar system in space (the movement of the solar space, 1783), Herschel transmitted his passion for the sidereal universe to his son John and his sister Caroline Lucretia (1750-1848), who soon distinguished himself as advantageous for his elder brother disciple, to discover on their own three nebulae and eight comets.

Anecdotally, include that the great astronomer of Hanover was built, by express order of the Spanish King Carlos IV (1748-1819), a magnificent telescope of twenty-five feet long, equipped with a mirror of three feet in diameter, which was installed at the Royal Observatory in the gardens of the Buen Retiro in Madrid. Considered one of the best of his time (as competed in quality with which handled the own Herschel in his Observatory of Datchet), was brutally destroyed by Napoleon's troops during the war of independence (1808-1814).

Member of the Paris Academy of Sciences, the Royal Society of London (Royal Society) and the Astronomical Society of the same city (Royal Astronomical Society), Frederick William Herschel was honored with the title of Sir in 1816, and award, among other awards and honors, posthumously, with the Gold Medal of the Royal Astronomical Society (1826) and the Medal of the Academy of Sciences of Prussia (1846). Much of his writings were collected in the annals of the Royal Society London.

JRF

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