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John Couch AdamsAdams, John Couch (1819-92). Born in Landeast, Cornwall, he studied at St John’s College Cambridge between 1839 and 1843 when he became a fellow of Pembroke College. In 1841 he began to study the motions of Uranus, convinced that their irregularities were caused by an undiscovered planet. In 1845 he gave predictions for the position of this new planet to the director of Cambridge University, however, nothing was done. As a result the predictions of Urbain Le Verrier, although made after Adams, were pubished first, and it was these which led to the eventual discovery of the planet Neptune by Johann Galle. In 1858, Adams became Regius professor of Mathematics at St Andrews Edinburgh, Scotland, and, in 1859, succeeded Peacock as Lowdean Professor of Astronomy and Geometry at Cambridge, where he stayed until 1891. In 1861 he became Director of Cambridge Observatory. Although he is best remembered for his work in the discovery of Neptune, this was by no means his only significant achievement. His study of the Leonid meteor shower in 1866 showed that the meteors followed a cometary orbit. From this he concluded that they must be associated with a comet. Further study confirmed this and showed the comet, in this case, to be P/Temple-Tuttle. His study of the motion of the Moon yielded more accurate results than those by mathematician Pierre-Simon Laplace.
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George Biddell AiryAiry, George Biddell (1801-92). English astronomer. Born in Alnwick, Northumberland, he graduated from Trinity College, Cambridge, in 1823. He became professor of mathematics there in 1826, and of astronomy in 1828. He was appointed as the seventh Astronomer Royal in 1835 and Director of the Greenwich Observatory, which he completely re-organised. In 1851 he installed a transit telescope, establishing the point of 0° longtitude. In 1872 he recieved a knighthood. He died in Greenwich on January 2nd 1892.
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Robert Grant AitkenAitken, Robert Grant (1864-1951). US astronomer, born in Jackson, California and educated at Williams College, Massachusetts Working at the Lick Observatory at Mount Hamilton, California, he began a survey of double stars in 1899 which was not finished until 1915. He and his assistant, W.J. Hussey, between them discovered nearly 4,500 new binary systems. The statistical results of his survey were published as Binary Stars in 1918 and revised as New General Catalogue of Double Stars in 1935. In 1926 the Astronomical Society of the Pacific awarded him their highest honour – the Catherine Wolfe Bruce Gold Medal for lifetime contributions to astronomy. In 1932 the Royal Astronomical Society awarded him their Gold Medal. Aitken died on 29th October 1951 at Berkley, California; he has an asteroid named after him (3070), and a crater on the far side of the Moon.
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Friedrich Wilhelm August ArgelanderArgelander, Friedrich Wilhelm August (1799-1875). Born in Memel, East Prussia (now Kalaipeda, Lithuania), he studied at nearby Königsberg (now Kalingrad) under Bessel. In 1823 he went to Åbo, Finland, where he studied the proper motion of 500 stars and published the most accurate catalogue of the day on the subject. In 1827, when the observatory was destroyed by fire, he became professor and director of the observatory at Helsinki. In 1836 he became professor at Bonn and had an observatory constructed there. It was here that he did his most important work. His Uranometrica Nova introduced the estimation by steps method for determining stellar magnitudes with the naked-eye. Then, in an extension to work done by Bessel, he conducted a survey that was published as Bonner Durchmusterung (Bonn Survey) 1859-62 in which he catalogued the position and brightness of 324,198 stars. It was the last major catalogue to be produced without the aid of photography, and was of such value that it was reprinted as recently as 1950.
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Aristarchus of SamosAristarchus of Samos (310-230 BCE). A Greek astronomer who was the first to argue that the Earth moves around the Sun, for which he was widely ridiculed. It was hundreds of years later before anyone else seriously challenged the geocentric system. When he was young he studied under Strato of Lampsacus, one of Aristotle’s team. Little else is known about Aristarchus; only one short work by him has survived. It was called On the Sizes and Distances of the Sun and Moon, and describes how Aristarcus calculates that the Earth is about eighteen times further away from the Sun than from the Moon. The method he used relied upon the fact that when the Moon is exactly in second quarter it will form a right-angled triangle with the Earth and the Sun, and the relative lengths of the sides of the triangle can be determined by angular measurement. Although his result was wrong (the true ratio is about 400), his method was correct, and despite his error it is important as the first attempt to understand astronomical distances with anything more than guesswork, in fact, his inaccuracy was due to poor instruments rather than any inability on his part.
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Halton Christian ArpArp, Halton Christian (b.1927). US astronomer educated at Harvard and CIT, who specialised in identification of galaxies. In 1965 he published Atlas of Peculiar Galaxies, research into which led him to challenge the still widely held belief that red shift is a reliable indicator of distance. (see Edwin Hubble) He found that quasars were often associated with these peculiar galaxies even though the red shift of the galaxy, and that of the quasar did not always match. Although most astronomers still believe that quasars are unrelated to peculiar galaxies no one has yet been able to explain why quasars seem more numerous around them. Arp also did much research into globular clusters, globular-cluster-variable stars (now known as RR Lyræ stars), Cepheid variables, novæ, and extragalactic nebulæ.
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Francis BaileyBaily, Francis (1774-1844). Born in Newbury, Berkshire. Was a stockbroker until 1825 when he retired to devote his time to astronomy. Before this he had, in 1820, been instrumental in the founding of the Royal Astronomical Society [RAS]. In 1927 the RAS awarded him their Gold Medal for his work on their catalogue of 2,881 stars, He is best known for his description of the light effect called Baily’s Beads, which can be seen around the Moon just before, and just after a total eclipse of the Sun.
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Edward Emerson BarnardBarnard, Edward Emerson (1857-1923). Born in Nashville, Tennessee. From the age of nine he worked as an assistant in a photographic studio. Went on to take a job in the observatory at Vanderbilt University. In 1888 he went to work at the newly opened Lick Observatory in California. While he was there he discovered the fifth satellite of Jupiter, which he named Amalthea. In 1895 he went to serve at the University of Chicago, at the same time becoming astronomer at the Yerkes Observatory in Wisconsin. While at Yerkes he discovered a fast moving star in the constellation of Ophiuchus which became known as Barnard’s Star. This faint red dwarf star is the second closest to the Sun at a distance of just six light-years and has a proper motion of ten seconds of arc/year; making it faster than any other known star. Barnard was the first to discover the true nature of dark nebulæ, and subsequently went on to produce an authoritative catalogue of these nebulæ.
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Photo not availableBayer, Johann (1572-1625). A German lawyer and amateur astronomer, he is best remembered for a star catalogue which he produced in 1603, in which he introduced the system of allotting Greek letters to each of the brighter stars in each constellation. Thus the brightest star in Andromeda would be known as α Andromedæ, the second as β Andromedæ, and so on down to ω Andromedæ; a system which, athough containing a number of apparent errors, is still used today. This same star catalogue also introduced a number of new constellations, they were: –
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Jocelyn Bell-BurnellBell Burnell, Susan Jocelyn (b. 1943). Born in Armagh, educated at Glasgow and Cambridge Universities. While at Cambridge she was doing research into quasars when she noticed one that was emitting radio pulses at a frequency of precisely one every 1.337 seconds. At first it was thought that these must have an intelligent origin and so the quasar was named LGM (Little Green Men). However, Bell soon noticed three similar sources, each with a slightly different, though equally precise, pulse-rate, in widely spaced locations in the Galaxy. As a result, Bell realised that she had discovered a new type of object, a pulsar. Between 1968 and 1982 she worked at the University of Southampton, doing research into gamma-ray astronomy then, at the Mullard Space Science Laboratory, University College, London, she did research in X-ray astronomy. From there, she went to the Royal Observatory, Edinburgh, where she worked in both optical, and infra-red astronomy until 1991, when she was appointed professor of physics at the Open University, Milton Keynes.
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Friedrich Wilhelm BesselBessel, Friedrich Wilhelm (1784-1846). Born in Minden, NW Germany. As an amateur, in 1804, he wrote a paper on Halley’s comet. This got him a post as an assistant at Lilienthal Observatory. In 1808 he was commissioned by the Prussian government to construct the first large German observatory at Königsberg. When it was completed, in 1813, Bessel became its first director, and remained there for the rest of his life. Among the more important contributions that Bessel made to astronomy were the measuring of the distance to the star 61 Cygni by means of parallax, thereby allowing a more accurate measurement of the positions of celestial objects. Bessel also predicted the position of Neptune.
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Photo not availableBode, Johann Elert (1747-1826). Born in Hamburg, Germany, he was self-taught. In 1786 he became director of the Berlin observatory where he stayed until 1825. While he was there he compiled two atlases, Vorstellung der Gestirne and Uranographia, which described the positions of over 17,000 stars and included some of the new objects discovered by William Herschel; in fact it was Bode who first suggested that Herschel’s new planet should be named Uranus. During the compiling of the first of these atlases, Bode introduced a number of new constellations, none of which have survived to our day; they were: –
  Bode is best known, however, for the formulation of a mathematical sequence known as Bode’s law.
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Bart Jan BokBok, Bart Jan (1906-1983). Dutch-American astronomer, born in Hoorn, Netherlands, and educated at Lieden and Groningen. He was joined at Lieden by Gerard Kuiper and was tutored by Enjar Hertzsprung and Jan Oort. In 1928 he met American astronomers Priscilla Fairfield and Harlow Shapley at the General Assembly of the IAU. Shapley invited him to Harvard University the following year, an offer which he accepted. Also in 1929 he married Miss Fairfield. He remained at Harvard until 1957, becoming a professor in 1947. From there he moved to Australia where he became the head of the Department of Astronomy at the Australian National University and director of the Mount Strombolo Observatory. While at the ANU he oversaw the establishment of the Anglo-Australian Observatory. In 1966 he returned to the States to take up the Directorship of the Steward Observatory at the University of Arizona. He did much important and varied work, but is best remembered for his study of the small dust globules that now bear his name.
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Photo not availableBond, George Phillips (1825-65). Born in Dorchester, Massachusetts, the son of William Cranch Bond, he was educated at Harvard and worked under his father at the college observatory. He did much work on the determination of stellar magnitude by photographic means. Indeed he was a pioneer in the field of astronomical photography, using it to map the sky and determine stellar parallax. His photographs of the Moon caused a sensation at the time. He also did extensive work in the study of comets, discovering 11 in the process. When his father died in 1859 he took over the directorship of Harvard College observatory.
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William Cranch BondBond, William Cranch (1789-1859). Born in Falmouth, Maine, he was a watchmaker and an amateur astronomer. He was one of the discoverers of the comet of 1811. His fame as an amateur astronomer led to a commission from Harvard College to investigate the equipment at observatories in England, and subsequently, he was asked to move his own private observatory into their premises. He therefore, became the first director of Harvard College observatory. Working along with his son, George Phillips Bond, he discovered the eighth satellite of Saturn, which he named Hyperion, and also the Crepe ring. As a result of observing that stars could be seen through the Crepe ring, they came to the conclusion that Saturn’s rings were not solid.
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James BradleyBradley, James (1693-1762). Born in Sherbourne, Dorset he studied theology at Oxford. However, his interest in astronomy caused him to resign his post as the Vicar of Bridstow in 1721 to become Professor of Astronomy at Oxford. In 1742 he became the third Astronomer Royal, on the death of Edmund Halley. He discovered the aberration of starlight, which enabled him to calculate the speed of light. He also compiled a catalogue of the positions of 60,000 stars and discovered the nutation of the Earth’s axis.
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Tycho BraheBrahe, Tycho (1546-1601). Born in Skåne, Sweeden, which was then under Danish rule, and studied in Copenhagen, and in Germany. His observations of the planets enabled Kepler to prove that the planetary orbits are ellipses and not circles. He also proposed a new constellation called Antinoüs in 1559, which was subsequently rejected. In 1590 he had a little more success when he introduced and charted the constellation Coma Berenices, which has remained to this day.
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Annie Jump CannonCannon, Annie Jump (1863-1941). Born in Dover, Delaware, USA. Studied at Wellesley and Radcliff colleges. Went to Harvard College Observatory in 1896, became curator of astronomical photographs in 1911, and curator and astronomer in 1938. By studying photographs she was able to discover 300 new variable stars, but she specialised in stellar spectra. She reformed the system of classifying stellar spectra (see spectrum) and classified the spectra of 300,000 stars. This work, describing stars down to magnitude ten, was published in a ten-volume set and was finished in 1924. She later worked on the classifying of fainter stars.
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Photo not availableCassegrain, Laurent (1629-1693). Not an astronomer, but, an inventor. Very little is known about his life except that he was born in Chartres, France, where he later became a Catholic priest. He invented a system of mirrors that improved the design of the reflecting telescope which was originally invented by Newton by reflecting the light back through the main mirror. His intention was to increase angular magnification. However, it was later found that Cassegrain’s design also partly cancelled out spherical aberration.
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Giovanni Domenico CassiniCassini, Giovanni Domenico (1625-1712). Born in Nice (then in Italy), he worked as an assistant at an observatory near Bologna until 1650 when he was made professor of astronomy at the University of Bologna. In 1669 King Louis XIV of France invited him to build and run an observatory in Paris, which he did until he went blind in 1710. Much of Cassini’s most important work was done on the planets. He determined the rotation periods of Mars, Jupiter and Venus and discovered a gap in the rings of Saturn (now called the Cassini Division) as well as discovering four of Saturn’s satellites which he named Tethys, Dione, Rhea and Iepetus.
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Heinrich Ludwig d’Arrestd’Arrest, Heinrich Ludwig (1822-75). Born and educated in Berlin, he worked at the Berlin observatory as an assistant to J.G. Galle, and helped in the successful search for the planet Neptune. Left in 1852, when he was appointed associate professor of astronomy at the University of Leipzig. In 1857 he became director of the observatory at the University of Copenhagen. Specialised in comet and asteroid work and also published improved positions for 200 nebulæ.
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Charles Adouin DollfusDollfus, Charles Adouin. Born 1924 in Paris, educated at the Lycee Janson-de-Sadly and at the Faculty of Sciences in Paris, where he gained his doctorate in mathematical sciences. In 1946 he began working as an astronomer at the Meudon Observatory. Most of his important work has been on the planets. In 1950 he became the first to detect a faint atmosphere on Mercury, he also established that the Moon does not have one. In 1966 he discovered Saturn’s innermost satellite, Janus.
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Giovanni Battista DonatiDonati, Giovanni Battista (1826-73). Born and educated in Pisa, he worked mainly on comets, although he also did some important early work on stellar spectroscopy. His greatest discovery was the great comet of 1858 which was named after him. Donati’s Comet was extraordinary not only in its brightness, but also in the fact that, aside from its main tail, it had two narrow extra tails.
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Henry DraperDraper, Henry (1837-82). Born in Virginia and studied medicine at the University of the City of New York. Whilst travelling in Europe he became interested in telescope-making and photography. In 1860 he was appointed professor of natural science at the University of the City of New York and built an observatory in Hastings-on-Hudson, New York. By 1873, he had devised a spectrograph that he used to spectrographically study the Moon, Mars, Jupiter, the comet 1881 III, and the Orion Nebula. Draper left a legacy to Harvard College Observatory, which they used to carry out a programme, between 1886 and 1897, to establish a comprehensive classification scheme for stars and a catalogue of spectra. The result was published as the Henry Draper Catalogue.
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John Louis Emil DreyerDreyer, John Louis Emil (1852-1926). Born and educated in Copenhagen, he moved to Ireland in 1874 when he was appointed assistant at Lord Rosse’s observatory at Birr Castle in Parsonstown. In 1877 he published the first of two volumes which presented data on new nebulæ and corrections to the catalogue of nebulæ and star clusters produced by John Herschel. In 1878 he moved to the University of Dublin’s Dunsink Observatory. From 1882-1916 he was director of the Armagh Observatory. While he was there he did the work for which he is most widely remembered. As a result of publishing, in 1886, the second volume of the work he had started nine years earlier, The Royal Astronomical Society invited him to compile a comprehensive new catalogue. The result was The New General Catalogue of Nebulæ and Clusters of Stars (NGC), published in 1888 and two Index Catalogues (IC), published in 1895 and 1908. Such was the impact of this work that even today most nebulæ, star clusters and galaxies are known by their NGC or IC number.
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Frank Watson DysonDyson, Frank Watson (1868-1939). Born in Ashby-de-la-Zouch, Leicestershire, he studied at Cambridge. From 1906 to 1910 he was Astronomer Royal for Scotland, and from 1910 to 1933, Astronomer Royal for England. In 1924 he initiated the broadcasting of the Greenwich time signal on BBC radio. His work, along with that of a number of other astronomers, on the proper motion of stars was seen as the first evidence of the rotation of our Galaxy.
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Johann Franz EnckeEncke, Johann Franz (1791-1865). Born in Hamburg, he studied at the University of Göttingen. Between 1825 and 1865 he was director of the Berlin Observatory. His work on star charts contributed to the discovery of the planet Neptune. The work took nearly twenty years and was completed in 1859, but the charts were soon improved upon by Friedrich Argelander. Encke did much work with comets and the comet he discovered is still known as Encke’s comet. He also discovered a gap in Saturn’s rings, which was named after him.
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John FlamsteedFlamsteed, John (1646-1719). Born near Derby, and educated at Cambridge. He began his astronomical studies as an amateur at home whilst serving as the Rector of Burstow, Surrey, by observing the 1662 eclipse and then, corresponding with other astronomers about it. In 1675 he was appointed astronomer to Charles II, and therefore became the first Astronomer Royal. He was, however, provided with no equipment but had to supply his own. This lead to his building the Royal Observatory at Greenwich, London, the following year. Flamsteed then began a systematic cataloguing of the positions of the stars, Moon, and planets. A result of which was the introduction of two new constellations: –
  • Mons Mænalus, and
  • Cor Caroli
  Neither of these constellations has survived. However, the name Cor Caroli has survived as the proper name of α Canum Venaticorum. Undeterred by the non-acceptance of his new constellations, Flamsteed continued with his cataloguing project, the results of which were published in 1725 as Historia Coelestis Britannica. In this publication the stars were each given numbers according to their position within a constellation (starting in the west of the constellation and working east) which are still in use today, particularly with stars which do not have a Bayer letter. Thus the star Pleione in the Pleiades is also known as 28 Tauri.
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Galileo GalileiGalilei, Galileo (1564-1642). Born and educated in Pisa, Italy, in 1589 became professor of mathematics at the university there. In 1592 he moved to Padua, and in 1610 he was appointed chief mathematician to the Duke of Tuscany. He is known as the ‘Father of Modern Astronomy’ because of his being the first great telescopic observer. Sometimes he is erroneously credited with the invention of the telescope, however this is an honour that rightfully belongs to Hans Lippershey. Nevertheless, Galileo did make some improvements to telescope design. Among the many discoveries credited to Galileo are; the discovery of the satellites of Jupiter, the phases of Venus, the gibbous aspect of Mars, the starry nature of the Milky Way and sunspots. In 1632 he published Dialogues on the Two Chief Systems of the World which discussed the relative merits of the geocentric system and the heliocentric system. Galileo came down heavily in favour of the heliocentric system, and so angered the Catholic authorities. He was subsequently forced to recant by the Inquisition.
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Johann Gottfried GalleGalle, Johann Gottfried, (1812-1910). Born in Grafenhainichen, Saxony, Prussia, (now part of Germany) and educated in Berlin. Worked at the Berlin Observatory, where he served as assistant director under Johann Franz Encke from 1835 until 1851, when he was made director of the Breslau Observatory (now in Wroclaw, Poland). Working with Heinrich d’Arrest, and using the predictions of Urbain LeVerrier, he discovered Neptune on 23rd September 1846. He also discovered three comets, as well as Saturn’s Crepe ring and the ice caps of Mars and later suggested a method for measuring the scale of the solar system. He died in Potsdam, Germany on 10th July 1910
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Jesse Leonard GreensteinGreenstein, Jesse Leonard (1909-2002). US astronomer who took part in the discovery of the interstellar magnetic field and the discovery and interpretation of quasars. Born in New York, he was educated at Harvard. His early work involved the spectroscopic investigation of stellar atmospheres; later work included a study of the structure and composition of white dwarf stars. In 1948, he joined the California Institute of Technology and also the staff of the Mount Wilson and Palomar Observatories. He became professor of astrophysics 1971. During the 1970s he guided both the US space agency NASA and the National Academy of Sciences in their policies. He confirmed the hypothesis of US astronomer Maarten Schmidt (1929- ) that the emission lines of quasars could be explained by a shift in wavelength. In collaboration with Schmidt, Greenstein proposed a detailed physical model of the size, mass, temperature, luminosity, magnetic field, and high-energy particle content of quasars. By 1978 Greenstein had discovered some 500 white dwarf stars. His research enabled him to pinpoint the problems of explaining the evolutionary sequence that links red giant stars with white dwarfs. This initiated spectroscopic studies of such stars from space.
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George Ellery HaleHale, George Ellery (1868-1938). Born in Chicago and studied at MIT. In 1889 he invented the spectroheliograph. In 1897 he founded the Yerkes Observatory in Wisconsin, and built there the world’s largest refracting telescope (40 in). In 1904 he moved to Mount Wilson where, in 1917 he established, what was then, the world’s largest reflecting telescope with a 100-in(2.5m) mirror.
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Edmund HalleyHalley, Edmund (1656-1742). Born near London he studied at Oxford but left without gaining a degree. In 1676 he went to St Helena for two years charting the stars of the southern hemisphere. He studied reports of cometary sightings of 1456, 1531, 1607, and 1682 and deduced that they all represented the same comet. He announced in 1705 that this comet would return in 1758. When it did return exactly on time, and sadly, sixteen years after Halley’s death, the comet was named Halley’s Comet in his honour. In 1680 he proposed a new constellation which he called Robur Caroli, however, his suggestion was not generally accepted and soon fell from use. In 1720 he became the second Astronomer Royal.
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Heraklides of PontusHeraklides of Pontus (388-315 BCE). Philosopher and astronomer, born in Heraklea (now Zonguldak, Turkey). He emigrated to Athens where he studied at the Academy of Plato, under Speusippus. He was one of the first to realise that the Earth turns on its axis every 24 hours. Also suggested that the planets orbit the Sun rather than the Earth, thereby contradicting the accepted model of the universe put forward by Aristotle, whom he is thought to have come into contact with whilst studying at the Pythagorean schools. What we know of the work of Heraklides we know second hand because all his writings have been lost.
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Caroline Lucretia HerschelHerschel, Caroline Lucretia (1750-1848). Born in Hanover, the sister of William Herschel, she received no formal education. In 1772 she joined her brother at Bath, where she performed as a singer and William taught her mathematics and English. Gradually Caroline’s role changed and she began to help her brother as he worked on his catalogue of nebulæ and star clusters. William gave her a telescope and she began a systematic search for comets and found eight between 1786 and 1797. She then began a project of cross-referencing and correcting Flamsteed’s catalogue, after which she devoted 25 years to looking after the education of her nephew, John. After William’s death she assisted John in his work as a result of which she completed a catalogue of 2,500 nebulæ in 1828, for which the Royal Astronomical Society awarded her a gold medal. She remained active until her death at the age of 97.
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William HerschelHerschel, Friedrich Wilhelm (always known as William Herschel — 1738-1822). Born in Hanover, he joined a regimental band at the age of 14. In 1757 he moved to England and worked as a musician and composer. During this time he taught himself mathematics and astronomy, and built his own reflecting telescope. In 1781 he discovered the planet Uranus, as a result of which he was offered the post, on the following year, of Private Astronomer to King George III. Working with his sister, Caroline, he catalogued over 800 binaries and 2,500 nebulæ. He was knighted in 1816.
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John HerschelHerschel, John Fredrick William (1792-1871). Born in Slough, the son of William Herschel, and educated at Cambridge. Devoted himself to private research. Went to South Africa in 1834 and spent the next five years mapping the southern skies from the Cape of Good Hope Observatory. Produced the General Catalogue of 10,300 Multiple and Double Stars, which was published posthumously. He also produced the General Catalogue of Star Clusters and Nebulæ, which was later improved upon by Louis Dreyer to become today’s NGC Catalogue.
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Enjar HertzsprungHertzsprung, Ejnar (1873-1967). Born in Frederiksberg, Denmark, and studied chemical engineering at the Frederiksberg Polytechnic. After working in Russia, he was employed at observatories in Denmark and Germany where, in 1905, he proposed the standard for absolute magnitude which is still in use today. He also, as a result of this, devised a diagram (independently arrived at also by US astronomer Henry Russell), known as the Hertzsprung-Russell diagram, which details the evolution and spectral type of stars.
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Johannes HeveliusHevelius, Johannes (1611-87). Born Johannes Hewelcke in Danzig, Germany (now Gdansk, Poland). An amateur astronomer who worked as a brewing merchant and a city councillor during the day but spent his evenings in his rooftop observatory at his home. Published a detailed map of the Moon, discovered four comets, and produced an atlas of 1,500 stars which was published by his wife three years after his death. A number of new constellations were introduced in this atlas, most of which exist to this day. They were;
  • Camelopardus (now known as Camelopardalis)
  • Canes Venatici
  • Vulpecula et Anser (now known as Vulpecula)
  • Lacerta
  • Leo Minor
  • Lynx
  • Scutum Sobietskii (now known as Scutum)
  • Monoceros
  • Sextans Uraniæ (now known as Sextans)
Two others were proposed, but did not gain general acceptance;-
  • Triangulum Minor, and
  • Cerberus
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HipparchusHipparchus   (c190-120 BCE). Greek astronomer and mathematician, born in Nicaea, Bythnia (now Iznik, Turkey) and later lived on Rhodes and in Alexandria, Egypt). Invented trigonometry and calculated the length of the solar year and the lunar month. In 134 BCE he noticed a new star in the constellation of Scorpius and this inspired him to put together a star catalogue (the first of its kind) which he completed in 129 BCE. His finished work, which included the magnitude of each star, was still current when Halley used it some 1,800 years later.
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Edwin Powell HubbleHubble, Edwin Powell (1889-1953). Born in Marshfield, Missouri, and educated in Chicago, and at Oxford University in the UK. In 1914 he joined Yerkes Observatory, and in 1919 Mount Wilson in California. In 1923 he discovered a Cepheid variable in the Andromeda galaxy, and so proving that it lay far beyond our own Galaxy and was, in fact, a separate galaxy in its own right. This realisation led to further research which revealed that galaxies were numerous and varied. Hubble then set about classifying them by their various types (see Hubble classification. He also noticed that all the spectra of these galaxies were red-shifted. By studying this effect he was able to formulate, in 1929, what became known as Hubble’s Law, which states that galaxies are moving apart at a rate which increases with their distance.
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Dr Russell HulseHulse, Dr Russell (b. 1950). US physicist and radio astronomer, born in New York City. In 1970, he received his bachelor’s degree in physics from The Cooper Union, a college in lower Manhattan. He then went on to graduate studies at The University of Massachusetts in Amherst, where his childhood interest in amateur radio undoubtedly influenced his decision to explore radio astronomy as his graduate thesis subject. Whilst there, and under the supervision of J.H. Taylor, he discovered a new type of pulsar, called a binary pulsar. After completing his Ph.D. in 1975, he accepted a two year, post-doctoral appointment at the National Radio Astronomy Observatory in Charlottesville, Virginia. From there, he took a position at the Princeton University Plasma Physics Laboratory (PPPL) with the plasma modelling group, where he remains today.
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Christiaan HuygensHuygens, Christiaan (1629-95). Dutch mathematical physicist and astronomer, born in The Hague. He was tutored at home until the age of sixteen and then studied law and mathematics at Leiden and Breda. His studies in centrifugal force dealt with several difficult points that Newton had carefully avoided. In astronomy his most important contributions include the invention of an eyepiece to reduce chromatic aberration, and the discovery of Titan, the largest of Saturn’s satellites, as well as the true shape of Saturn’s rings.
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Johannes KeplerKepler, Johannes (1571-1630). Born in Weil der Stadt in Bader-Württemburg, Germany, and studied at Tübingen. He was a profoundly religious man and his writings contain numerous references to God. He became an assistant to Tycho Brahe in 1600, and was one of the first supporters of the heliocentric system introduced by Copernicus. He was a mathematician as well as an astronomer, and applied this skill to the study of observations of the planets made by Brahe. The result was the formulation of a set of principles, published between 1609 and 1619, which became known as Kepler’s Laws of Planetary Motion.
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Mikolaj Kopernik (Copernicus)Kopernik, Mikolaj (1473-1543). Better known by the latinised version of his name, Copernicus. He was born in Toruné in the Vistula, Poland, (then in East Prussia) and studied mathematics, astronomy, classics, medicine and law at Kraków and at various universities in Italy. He was convinced of the error of the geocentric system and spent thirty years working on a new theory. He felt that apparent anomalies in the motion of the planets could be explained by a heliocentric system. However, because of the fear of reprisal from the Roman Catholic Church he would not publish it. It eventually appeared in print, as De Revolutionibus Orbium Cœlestrium, only after his death. He had however, previously published an anonymous text entitled Commentariolus in which he outlined the material which he later presented in De Revolutionibus.
  The publication of De revolutionibus was overseen by a Lutheran minister who, without Copernicus’ permission, inserted a preface stating that the theory presented was intended merely as an aid to the calculation of the planetary positions, and was not a statement of reality. Although this compromised the value of the text in the eyes of many astronomers, it also saved it from instant condemnation by the Roman Catholic Church. It was not put on the index of forbidden books until 1616.
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Gerard Peter KuiperKuiper, Gerard Peter (1905-73). Born Gerrit Pieter Kuiper in Harenkarspel, Netherlands, he graduated from the University of Leiden in 1927. After recieving his PhD in 1933 he emigrated to the US. He joined the staff of the Yerkes observatory and was its director from 1947-49 and 1957-60. In 1948 he discovered Miranda, Nereid, and the atmospheres of Mars, and Titan. In 1951 he predicted the existence of comet-like objects beyond the orbit of Neptune. This area became known as the Kuiper Belt. When he left Yerkes Observatory, in 1960, he became director of the Lunar and Planetary Laboratory at the University of Arizona, where he remained until his death (in Mexico City) in 1973.
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Nicolas Louis de Lacaille Lacaille, Nicolas Louis de (1713-62). Born in Rumigny, near Rheims, France. In 1750 he went to the Cape of Good Hope Observatory, South Africa, where he spent nearly five years cataloguing the positions of stars down to magnitude seven. In the process, he charted and named 14 new constellations, choosing contemporary scientific names for them. The names were:
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  • Apparatus Sculptoris (now known as Sculptor);
  • Fornax Chemica (now Fornax);
  • Horologium;
  • Reticulum Rhomboidalis (now known as Reticulum);
  • Cæla Sculptoris (now known as Cælum);
  • Equuleus Pictoris (now known as Pictor);
  • Pixis Nautica (now known as Pyxis);
  • Antlia Pneumatica (now known as Antlia);
  • Octans;
  • Circinus;
  • Quadra Euclidis (now known as Norma);
  • Telescopium;
  • Microscopium; and,
  • Mons Mensæ (now known as Mensa)
  There was also a fifteenth constellation, called Musca Australis (now known as Musca), which replaced the Bayer constellation Apis.
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Joseph-Jérôme LeFrançois de LalandeLalande, Joseph-Jérôme LeFrançois de, (1732-1807). Born in Bourg-en-Bresse, near Lyon, France, and studied at the Jesuit college in Lyon and had intended to join the Jesuit order before his parents persuaded him to continue his education. The result was that he studied law in Paris, where he also gained his enthusiasm for astronomy, becoming involved with a project to measure the distances of the moon and Mars by means of parallax. By observing the transits of Venus in 1761 and 1769 he was helped to calculate the distance to the Sun, and thereby, the size of the Solar System. In 1776 he proposed a new constellation which was to be named after Messier, however, this idea was rejected. He also compiled a catalogue of 47,000 stars.
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William Lassell
Photo © Liverpool Astronomical SocietyLassell, William (1799-1880). English astronomer, born in Bolton, Lancashire. In 1815 he moved, with his family to Liverpool where he was apprenticed to a merchant’s office (believed to be in the drinking trade). In 1821 he constructed a 7½″ Gregorian reflecting telescope. In 1824, two years after finishing his apprenticeship he started a brewing business. In 1836 he convinced the Borough of Liverpool to establish an observatory, which was sited near the present pier head and completed 8 years later. In 1845 he built a 24″ telescope at his new home in West Derby, Liverpool and, the following year he discovered Triton. In 1848 he, independently of  W Bond, discovered Hyperion. He also discovered, In 1851, Ariel and Umbriel, and after setting up a 24″ reflecting telescope in Malta the same year, he discovered 600 nebulæ with it. Even in those days pollution hampered observations in Liverpool so, in the 1860s he moved to Maidenhead, Kent, where he eventually died.
Photo copyright © Liverpool Astronomical Society
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Henrietta Swan LeavittLeavitt, Henrietta Swan (1868-1921). Born in Lancaster, Massachusetts, the daughter of a Congregational minister. She attended Oberlin College and the Society for Collegiate Instruction of Women (later Radcliffe College). As a senior in 1892, she discovered astronomy. After graduation she took another course in it, but then spent several years at home when she suffered a serious illness that left her severely deaf. In 1895 she volunteered for Harvard College Observatory and joined the permanent staff seven years later, specialising in photographic stellar photometry. She discovered 2,400 new variable stars and four novæ and discovered the Period-Luminosity Relationship. She also developed a standard for measuring photographic magnitudes which was accepted by the International Committee on Photographic Magnitudes in 1913.
  Leavitt was not allowed to pursue her own topics of study, but researched what the head of the observatory assigned. Because of the prejudices of the day, she didn’t have the opportunity to use her intellect to the fullest, but a colleague remembered her as “possessing the best mind at the observatory,” and a modern astronomer calls her “the most brilliant woman at Harvard.” She worked at the Harvard College Observatory until her death from cancer in 1921.
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Urbain Jean Joseph Le VerrierLe Verrier, Urbain Jean Joseph (1811-77). Born St Lô, Normandy, and studied at L’Ecole Polytechnique in Paris. He joined the staff in 1837 and ten years later, he became a professor. He worked at the Paris Observatory for most of his life and was made their Director in 1854, but his drive and efficiency made him unpopular, so in 1870 he was removed from the post. However, his successor died three years later so he was re-appointed, this time under the supervision of a council. His main claim to fame is often thought to be his prediction of the existence and position (accurate to less than 1°) of the planet Neptune, but, important though this was, it ignores the fact that Le Verrier’s work in resolving discrepencies in the motion of Mercury at perihelion provided important evidence that Einstein used in the formulation of his General Theory of Relativity, even though Le Verrier wrongly attributed the discrepencies to an unknown planet. Le Verrier was awarded the Royal Society Copley Medal in 1846 and was elected a Fellow of the Royal Society the following year, and a Fellow of the Royal Society of Edinburgh. He also has a Paris street, and a lunar crater named after him and, when Gustave Eiffel built his tower, he included the names of 75 of France’s most prominent scientists around the first stage; Le Verrier being among them. Le Verrier died 23 September 1877, in Paris.
Picture and much of the information in this article courtesy of St Andrews University, Edinburgh.
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Hans LippersheyLippershey, Hans (c1570-1619). Born in Wesel, Germany, he later moved to Middelburg, the capital of Zeeland, where he married in 1594 and became a citizen eight years later. He worked as a spectacle maker, however, new techniques in glass making which were introduced by the Italians in the 1590s encouraged him to experiment. The result of these experiments was an application, made in 1608, for a patent on a telescope. The patent, however, was rejected and subsequent applications for patents on similar instruments by two other lens makers make it difficult to decide who really was the first to invent the telescope. One thing is for certain, though, Lippershey’s application was the first. As a result, he is generally regarded as the true inventor.
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Percival LowellLowell, Percival (1855-1916). Born in Boston, Massachusetts, USA. He studied mathematics at Harvard. Spent 16 years as a businessman and diplomat before becoming a professor of astronomy at Massachusetts Institute of Technology in 1902. During this time he founded the Lowell Observatory at Flagstaff, Arizona. (1894) It was his calculations that led to the discovery of Pluto by Clyde Tombaugh in 1930. He did much other important work but, sadly, he is most remembered for his belief that the canals on Mars, announced by Schiaparelli, were of artificial construction.
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Charles MessierMessier, Charles (1730-1817). Born in Badonviller, Lorraine. Joined the Paris Observatory where he joined in the search for Halley’s Comet which had been predicted to return that year. He was one of the first people to spot it and, as a result of this, he decided to dedicate the rest of his life to comet hunting, in fact King Louis XV nicknamed him the Comet Ferret. However, instead of comets he invariably found objects that later proved to be nebulæ. After a number of these false sightings he decided, in 1760, to compile a catalogue of these nebulæ and star clusters. This project took him 24 years, and resulted in a catalogue of 100 objects (later enlarged to 110) which is still widely used today. For instance, The Andromeda galaxy is also known as M31 because it is the thirty-first object in Messier’s catalogue.
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Isaac NewtonNewton, Isaac (1642-1727). English physicist and mathematician, born at Woolsthorpe Manor, in Lincolnshire. Studied at Cambridge University, where, in 1669, he became a professor. Is best remembered for his Universal Law of Gravitation, which he began studying in 1665, as legend has it, inspired by seeing an apple falling from a tree. He set out this law in Philosophiæ Naturlais Principia Mathematica in 1687. He also found that his theory explained the laws of planetary motion. As a by-product of research into light and prisms he developed a reflecting telescope.
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Heinrich Wilhelm Mathäus OlbersOlbers, Heinrich Wilhelm Mathäus (1758-1840). Born near Bremen, in Germany. His main interest was in comets however, whilst searching for a supposed missing planet between Mars and Jupiter, he discovered two asteroids, Pallas (1802) and Vesta (1807). He also attempted to explain what has become known as Olbers’ paradox that asks why, if space is infinite and filled with stars, the sky at night is dark. He theorised that space is not absolutely transparent and that interstellar matter absorbs minute amounts of starlight, causing stars to appear as points of light. It is now generally accepted that darkness is a by-product of red shift caused by stellar recession. Olbers discovered a number of comets and calculated the orbits of another eighteen.
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Jan Hendrik OortOort, Jan Hendrik (1900-92). A Dutch astronomer, born in Franeker, Friesland. He studied at Groningen and spent most of his career at Leiden. In 1927 he calculated the size of the Galaxy, the Sun’s distance from the centre and proved that the Galaxy is rotating. He also led a Dutch team which discovered the spiral structure of our Galaxy and the location of its centre. He is best known however, for his proposal that a vast cloud of comets exists at the edge of the Solar System. It has now been generally accepted that this cloud exists and it has been named the Oort Cloud (see Kuiper Belt). In 1942 he was awarded the Catherine Wolfe Bruce Medal by the Astronomical Society of the Pacific for “distinguished services to astronomy”, however because of wartime restrictions it was not presented formally until 1946.
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Giuseppe PiazziPiazzi, Giuseppe (1746-1826). An Italian astronomer, born in Ponte di Valtellina (now in Switzerland) and studied in various Italian cities. In 1764 he became a monk and, in 1779, professor of mathematics at Palermo Academy in Sicily. In 1790 he became director of Palermo observatory and in 1817 he also became director of the observatory in Naples. In 1801, whilst he was at Palermo, he became the first person to identify an asteroid, which he called Ceres. Then in 1803 he published a catalogue of 6,748 stars whose positions he noted with unheard of accuracy.
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Claudius PtolemæusPtolemy (Claudius Ptolemæus). Known as ‘Prince of Astronomers’, he lived in Alexandria in Egypt, from about 120-180 AD. Nothing is known about his life, and his greatest work has come down to us by way of an Arabic translation called the Almagest (hence the name of this site). He produced a star catalogue, based upon an earlier one by Hipparcus, and also ‘perfected’ the geocentric system.
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Olaus Christensen RömerRömer, Olaus Christensen (1644-1710), also known as Ole or Olaf, his surname can also be spelt Roemer or Rømer. A Danish astronomer who was born in Århus, Jutland, and studied at Copenhagen University. His main claim to fame came from a study of the timing of the eclipse of Io by Jupiter whilst working at the Paris observatory. Noticing that the eclipse did not always correspond exactly to the predicted times he reasoned that the discrepancies were due to the variable distance between the Earth and Jupiter. By studying future eclipses of Io he was able to calculate the speed of light.
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Photo not availableRoyer, Augustin (fl 1679). French astronomer who established the names and boundaries of a number of modern constellations, particularly those seen from southern latitudes, such as Columba and Crux Australis as well as proposing some which were rejected. The rejected constellations include; Nubes Major (the Great Cloud), Nubes Minor (the Little Cloud), and Lilium (the Lily).
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Henry Norris RussellRussell, Henry Norris (1877-1957) Born in 1877 in Long Island, New York, the son of a Presbyterian minister. He attended private school in Princeton, New Jersey, then enrolled in the “local” university there. He graduated from Princeton University with honors in 1897 and remained on campus to take his doctorate three years later. In the spring of 1900 he began writing a column for Scientific American, which he continued for the next 40 years. In 1905 he accepted a post as instructor and, in 1912, the directorship of the observatory at Princeton. From then on, he passed the better part of 60 years researching most of the major problems associated with the new science of astrophysics. Working independently of Ejnar Hertzsprung, he created a diagram which charted the luminosity of stars as a function of their surface temperatures, it became known as the Hertzsprung-Russell diagram. Russell’s early work on eclipsing binary stars, much of it conducted with the assistance of his gifted protégé Harlow Shapley, led to the first systematic analysis of the variation of light received from these bodies. In the 1920s he initiated a series of quantitative investigations on the absorption-line spectrum of the Sun that enabled scientists to determine the abundance of various chemicals in the solar atmosphere.
Photo courtesy of Yerkes Observatory, University of Chicago
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Lewis Morris RutherfurdRutherfurd, Lewis Morris (1816-92). Born in Morrisania, New York, and studied at Williams College, Massachusetts. Worked mainly in spectroscopy and stellar photography.Devised a system for classifying stars by their spectra. Starting in 1858 he began producing a large number of excellent photographs of the Sun, Moon, Jupiter, Saturn, and stars down to fifth magnitude.
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Martin RyleRyle, Martin (1918-84). English radio-astronomer, born in Brighton, Sussex, he studied at Oxford University. During the second world war he worked on the development of radar for the RAF. After the war he was invited by J A Ratcliffe to join his team at Cavendish Laboratory to help investigate radio emission from the Sun. Starting in 1950, and working from various radio telescopes at Cambridge he helped to compile five catalogues of radio sources. Known as the Cambridge Catalogue Survey, the catalogues were designated 1C-5C. In recognition of his work he was appointed by Cambridge to a new Chair of Radio Astronomy in 1959, and between 1964 and 1967 was president of Commission40 of the International Astronomy Union. In 1972 he was appointed Astronomer Royal.
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Giovanni Virginio SchiaparelliSchiaparelli, Giovanni Virginio (1835-1910). Born in Savigliano, Piedmont (now part of Italy), he graduated from the University of Turin in 1854, then studied under Encke at the Royal Observatory in Berlin. After this he worked under Otto Wilhelm Struve at Pulkova Observatory in Ukraine. In 1860 he moved again, this time to Brera Observatory, Milan. Two years later he became its director. The instruments there were small, so he concentrated his efforts on meteors and comets, as a result of which he announced the discovery that swarms of meteors follow the same paths around the Sun as do comets. As a ‘reward’ for this, a more powerful instrument (22 cm/8.7 inch) was installed. This new instrument enabled him to study the planets more closely and in the next few years he won awards for his studies of Mercury, Venus, Saturn and Uranus. In 1877 a favourable conjunction encouraged him to study and map the surface of Mars. Throughout September of that year he spent many long hours at the telescope drawing a detailed map of Mars and naming the features, most of the names survive to this day. Despite all the good work that Schiaparelli did however, it is one aspect of his map of Mars for which most people remember him. He was convinced that he saw a network of lines criss-crossing the Martian surface and he called these lines Canali (channels or canals). Sadly, the controversy that these ‘canals’ generated overshadowed the rest of the work that he had done.
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Pietro Angelo SecchiSecchi, Pietro Angelo (1818-78). Born in Reggio nell’Emilia, Modena (now part of Italy) and joined the Society of Jesus in 1833, lecturing in physics and mathematics at the Collegio Romano from 1839. In 1848 he was driven into exile for being a Jesuit and went first to Stonyhurst College, England, then to Georgetown University in Washington DC. He returned to Italy 1849 as director of the observatory at the Collegio Romano and professor of astronomy. With English astronomer William Huggins, Secchi was the first person to adapt spectroscopy to astronomy in a systematic manner and he made the first spectroscopic survey of the heavens. He proposed that the differences in stellar spectra reflected differences in chemical composition. His classification system of 1867 is the basis of the modern system. Secchi was among the first to use the new technique of photography for astronomical purposes. By 1859 he had a complete set of photographs of the Moon. He was also the first to classify solar prominences, huge jets of gas projecting from the Sun’s surface.
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Carl Keenan Seyfert
photo courtesy of Vanderbilt University/ Dyer ObservatorySeyfert, Carl Keenan (1911-60). Born and educated in Cleveland, Ohio. In 1929 he went to Harvard to study medicine however, inspired by Bart Bok, he turned to astronomy. In 1936 he gained his PhD in astronomy with the thesis: ‘Studies of the External Galaxies’ which focused on the colours and magnitudes of galaxies. He then joined the staff of Yerkes Observatory and established the new McDonald Observatory. While there he studied the properties of faint B-type stars and continued his work on the colours of spiral galaxies. From there he went to Mt Wilson observatory, where he studied a class of active galaxies which is now known as Seyfert galaxies. Between 1942 and 1946 he returned to Cleveland to teach navigation to the armed forces. From there he went to Vanderbilt University in Nashville, Tennessee where he invigorated the astronomy programme and initiated a plan to build a new observatory. In December 1953 the new Arthur J Dyer observatory was completed and equipped with a 24-inch (61cm) telescope. Seyfert became director of the observatory and remained there for the rest of his life. He was killed in a car accident on 13 June 1960.
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Harlow ShapleyShapley, Harlow (1885-1972). Born in Nashville, Missouri, he originally intended to be a journalist and came into astronomy almost by accident. He studied at the University of Missouri (1910-11) and then at Princeton (where Russell was the head of the astronomy department). Russell was working on a new approach to the analysis of the light-curves of eclipsing binaries, trying to discover the properties of the constituent stars, Shapley was of great assistance in this. In 1914 Shapley got his PhD for a thesis on the orbits of 90 eclipsing binaries. He then joined the staff of Mount Wilson Observatory in California where he advanced the pulsation theory for Cepheid variables. His use of this theory to determine the distances of globular clusters resulted (in 1918) in the discovery of the dimensions of our Galaxy and the location of its centre. In 1921 he took up the directorship of Harvard College Observatory and remained there until he retired in 1952. His main project in those years was the study of galaxies, resulting in a number of catalogues.
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Friedrich Georg Wilhelm von StruveStruve, Friedrich Georg Wilhelm von (1793-1864). Born in Altona, Denmark (now in Germany). To avoid conscription he fled to Estonia in 1808 and studied at Dorpat University (now Tartu). He became a professor there and, in 1817, he became director of the Dorpat Observatory, which he equipped with a 9.5 inch (24cm) refractor that he used in a massive survey of binary stars from the north celestial pole to 15°S. He measured 3,112 binaries – discovering well over 2,000 – and catalogued his results in Stellarum Duplicium Mensuræ Micrometricæ (1837). [All of Struve’s catalogue entries are identified by the capital letter sigma (Σ)]. In 1835, Czar Nicholas I persuaded Struve to set up a new observatory at Pulkovo, near St. Petersburg, Ukraine. The observatory was completed in 1839 and he became its first director. In 1840 he became one of the first astronomers to detect parallax. In 1846 Struve published his observations of the absorption of stellar light in the galactic plane, which he correctly deduced to be caused by the presence of interstellar material.
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Otto Wilhelm von StruveStruve, Otto Wilhelm von (1819-1905). Born Otto Vasilievich von Struve, in Dorpat, Estonia, the son of Friedrich von Struve. He studied at Dorpat University and assisted his father at Pulkova Observatory, becoming deputy director in 1848 and director in 1862. As director he supervised the training of Giovanni Schiaparelli. Like his father, he became a leading authority on binary stars, publishing his own catalogue. The entries in his catalogue were prefixed with OΣ to distinguish them from those catalogued by his father.
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Joseph Hooton Taylor JrTaylor, Joseph Hooton, Jr (b. 1941). Born in Philadelphia, Pennsylvania, he studied at Haverford College, gaining a BA in 1963. In 1968 he gained a PhD in astronomy from Harvard University. From 1969 to 1981 he taught at the University of Massachusetts, in Amherst where he conducted prizewinning research in collaboration with graduate student Russell Hulse. In 1974, using the radio telescope at Arecebo, Puerto Rico, they discovered the first binary pulsar (PSR 1913+16). Studies of the orbits of this pair confirmed Einstein’s theory of gravitation which was included in his General Theory of Relativity.
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Clyde William TombaughTombaugh, Clyde William (b. 1906). Born in Streator, Illinois, he became an assistant at the Lowell Observatory in Flagstaff, Arizona, in 1929, and photographed the sky in search of an undiscovered but predicted remote planet. The new planet would be dim, so each photograph could be expected to show anything between 50,000 and 500,000 stars and, because of its distance from the Earth, any visible motion would be very slight. He solved the problem by comparing two photographs of the same part of the sky taken on different days. The photographic plates were focused at a single point and alternately flashed rapidly on to a screen. A planet moving against the background of stars would appear to move back and forth on the screen. Tombaugh found Pluto on 18 Feb 1930, from plates taken three weeks earlier. He continued his search for new planets across the entire sky; his failure to find any placed strict limits on the possible existence of planets beyond Pluto.
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