Attraction to astronomy

Huggins bought his first telescope around 1842, when he was about 15 years old. He probably had made his first acquaintance with optical instruments in his parents' shop, where his father or shop assistants would have used a magnifying glass to count the number of threads per inch in cloth samples. His parents encouraged his scientific interests by giving him a microscope sometime in his youth. He used the microscope to study plant and animal specimens, apparently with some squeamishness over the animal dissections. The biographical sketch goes so far as to suggest he eventually chose astronomy over biology because of his distaste for dissection: ''[Ajlthough he recognised the lawfulness of such experiments as were necessary for the benefit of mankind, he realized that he was too sensitive to do some of the work inevitably demanded by biological research.''8

Astronomy-related news in the next decade would certainly have fueled Huggins' interest in astronomy, and would have encouraged him to pursue it as an amateur. In March and April 1843, the London Times published almost daily accounts of the changing appearance of the ''Great Comet of 1843,'' a comet so bright, it could be seen in daylight. The comet, whose tail extended over an arc of 40° in the sky, attracted more than usual interest, both in Europe and the United States. In fact, it was by capitalizing on public interest in this comet that Harvard College raised money for its best telescope, the replica of Struve's 15-inch Great Refractor in Pulkovo.

In 1845 — by which time Huggins would have had enough experience with his own small telescope to start dreaming of larger ones—William Parsons, the third Earl of Rosse, made the astronomical discovery for which he is still remembered today, using a telescope that was for a long time the largest reflecting telescope in the world. In the late 1830s, Parsons set out on a quest to see if the nebulae that had eluded earlier attempts to resolve them into stars would be resolved by larger instruments than Herschel's. He built first a 3-foot aperture telescope, and then, in 1845, unveiled a truly gigantic telescope of 6 feet diameter. Shortly after he began using this monster or ''Leviathan'' telescope, as it came to be known, he announced the important discovery of spiral structure in some nebulae, illustrating his finding with a drawing (figure 6.2) of what we would now call the spiral galaxy M51. Parsons also became well known for his assertion, widely accepted at the time but now known to be

Figure 6.2 Drawing of the spiral galaxy M51 by William Parsons, third Earl of Rosse. Parsons constructed the largest reflecting telescope of his day (6 feet in diameter), and was the first to discern spiral structure in some of the so-called nebulae. His drawing of M51, the "whirlpool galaxy,'' made in 1845, accurately shows that galaxy's spiral arms. (Compare with the Hubble Space Telescope photograph of the same object, figure 10.4a.) The blob at the end of one of the arms is, in fact, a smaller companion galaxy, catalog number NGC 5195, interacting gravitation-ally with M51. Three years later, Parsons noted spiral structure in the galaxy known as M99. (Credit: Birr Scientific and Heritage Foundation, courtesy of The Earl of Rosse.)

Figure 6.2 Drawing of the spiral galaxy M51 by William Parsons, third Earl of Rosse. Parsons constructed the largest reflecting telescope of his day (6 feet in diameter), and was the first to discern spiral structure in some of the so-called nebulae. His drawing of M51, the "whirlpool galaxy,'' made in 1845, accurately shows that galaxy's spiral arms. (Compare with the Hubble Space Telescope photograph of the same object, figure 10.4a.) The blob at the end of one of the arms is, in fact, a smaller companion galaxy, catalog number NGC 5195, interacting gravitation-ally with M51. Three years later, Parsons noted spiral structure in the galaxy known as M99. (Credit: Birr Scientific and Heritage Foundation, courtesy of The Earl of Rosse.)

spurious, that he had succeeded in resolving the Orion nebula into stars.

In 1846, an amateur astronomer shared the spotlight with a professional in an outstanding piece of news, the discovery of Neptune, the eighth planet of our solar system, and its system of satellites. Neptune is not all that difficult to see; even Galileo may have seen it through his primitive telescope, according to historical research into his observing notebooks. The difficulty was to recognize it as a planet, slowly moving against the background stars in its stately 165-year orbit around the Sun, and not to mistake it for an eighth-magnitude star.

In the nineteenth century, Bessel and a number of other astronomers had predicted the existence of a massive planet beyond the orbit of Uranus, based on observed irregularities in Uranus's orbital motion. However, pinpointing the hypothetical planet's location from these perturbations had proved to be an extremely difficult problem in celestial mechanics. The French astronomer Urbain Le Verrier, at the Paris Observatory, solved the problem and was the first to have his predicted position for the planet checked. On 23 September 1846, astronomers at the Berlin observatory found Le Verrier's planet, the newest member of the solar system, approximately where Le Verrier said it would be. Just a few days after the Times of London reported this historic discovery, William Lassell, an English brewer and well-known amateur astronomer, found Neptune's largest satellite, Triton.

Even when professional astronomers led the way, amateur astronomers were often quick to follow their innovations. William Cranch Bond, the first director of the Harvard College Observatory, contributed stunning daguerrotypes of the Moon to the photography display at the Crystal Palace Great Exhibition. These photographic records of a celestial object elicited great enthusiasm from the public and prompted several amateur astronomers in London, including Huggins, to experiment with astro-photography.9

Whatever finally inspired Huggins—no clues emerge from the biographical sketch or his own writings—he committed himself to independent scientific research within a few years of the Great Exhibition. He became a fellow of the Royal Microscopical Society in 1852. In 1853, he bought a telescope of 5 inches aperture from the well-known maker, John Dollond, and the next year was elected to the Royal Astronomical Society, an organization that John Herschel had helped establish in 1820. The Royal Society itself, the mother institution to the more specialized societies, remained out of reach for Huggins; in 1846, its members had begun to limit membership to scientists who had already demonstrated significant accomplishment.

In the same post-Exhibition period when Huggins began his association with the Microscopical and Astronomical societies, his father fell seriously ill. Rather than take over the family business, Huggins sold it and moved himself and his parents to a house in a new development in Lambeth, south of London. Thereafter, Huggins appears to have drawn a modest income from rents. His father died shortly after the move, and Huggins occupied himself with taking care of his mother and pursuing his passion for astronomy.

Huggins' new house on Upper Tulse Hill included a large garden in the back where he could set up his telescope. But Huggins did more than trundle the instrument outside in fine weather. He hired a local carpenter to build an observatory with a 12-foot diameter dome. The observatory floor sat on columns stretching 16 feet above the ground, so that he could see above the trees and have access to the room from the second story of his house. Beginning in 1856 with a description of this observatory and its instruments, Huggins regularly offered news from ''Mr. Huggins' Observatory'' to readers of the Royal Astronomical Society's Monthly Notices.10

During his early years as an independent researcher, Huggins found a mentor in William Dawes, a well-respected amateur astronomer and friend of Lassell. In 1850, just a few years after Lassell's discovery of Neptune's satellite Triton, Dawes had discovered a previously overlooked ring in Saturn's system, a thin, translucent ring interior to the two brighter rings, known as the ''crepe'' ring for its textured appearance. Around 1858, Dawes sold Huggins a telescope with one of the best 8-inch lenses available, which Dawes himself had purchased from the American lens maker Alvan Clark. More importantly, Huggins appears to have learned from Dawes how to carry out a research program. He began documenting his observations with drawings and carrying out regular observations of objects he thought were of scientific interest.

In the early 1860s, less than 10 years after moving to Upper Tulse Hill and devoting himself to astronomy, Huggins embarked on an ambitious project that turned out successfully and catapulted him to prominence in the astronomical community. The turning point came in 1862 when he initiated a discussion on spectroscopy with his neighbor Dr. Miller. Credit for setting Huggins and other astronomers down a very productive path, however, belongs to the founders of spectroscopy, Gustav Kirchhoff and Robert Bunsen.

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