Markree Observatory was an astronomical observatory in County Sligo, Ireland. [1] [2] [3] The asteroid 9 Metis was discovered from this observatory in 1848 by Cooper's assistant Andrew Graham using a comet seeker telescope. [4] [2] The observatory was also home to the largest refractor of the early 1830s, which had a 13.3-inch (340 mm) aperture Cauchoix of Paris lens; the largest in the world at that time. The observatory also housed a number of instruments and was operated to varying degrees throughout the 19th century.
The observatory is noted for its discovery of the asteroid 9 Metis in 1848 as well as a 60,000 item star catalogue of the 1850s. [5] In the later 1800s it was operated again after a brief hiatus, and gained note for its meteorological observations and research on double stars. [5]
In 1830, Colonel Edward Joshua Cooper MP (1798–1863) eldest son of Edward Synge Cooper MP, and Ann, daughter of Henry Vansittart, Governor of Bengal, set up Markree Observatory on the grounds of Markree Castle near Collooney in County Sligo.
In 1831 Cooper acquired from Robert A. Cauchoix of Paris an objective of 13.3-inches (~33.78 cm) for which he paid £1200. In 1834 he mounted the lens on an equatorial mounting supplied by Thomas Grubb of Dublin. [6] For a number of years Cooper's big refractor was the largest in the world. He used the telescope to sketch Halley's comet in 1835 and to view the solar eclipse of 15 May 1836. [7]
Later a 5-foot (1.5m) transit and a 3-foot (0.9m) meridian circle, fitted with an interchangeable 7-inch (17.75 cm) glass were added, which was the largest at that time in 1839; also in 1842 a 3-inch comet seeker was added. [1] [2] [3]
The observatory had a Stevenson screen, invented in 1863. [8]
"The Observatory of Mr Cooper of Markree Castle –undoubtedly the most richly furnished private observatory known –is worked with great activity by Mr Cooper himself and by his very able assistant, Mr Andrew Graham." (Royal Astronomical Society, 1851) [9]
In 1848, Cooper's assistant, Andrew Graham, discovered the asteroid 9 Metis with a wide-field comet seeker telescope manufactured by Ertel. Graham resigned his post at Markree in 1860, but continued his research at Cambridge Observatory until his retirement in 1905. E.J. Cooper died in 1863, but the observatory remained active until the death of Edward Henry Cooper MP in 1902.
The Cauchoix telescope was installed inside a circular wall, but it had no dome or roof over it. [8] The enclosure has a diameter of 16-feet across. [8]
The telescope mounting was made by Grubb of Dublin. [5] (Grubb would make telescopes for a century and half, later known as Grubb-Parsons)
The telescope objective was doublet with 13.3 inches of aperture and 25 feet focal length. [10] The Grubb mounting had a clockwork drive and weighed almost 2.4 metric tons (2.6 US tons), which rested on a limestone pillar. [10]
The lens was ground by Cauchoix of Paris using glass blanks by Guinand. [11] The 13.3 inch lens was completed in 1831. [11]
Pierre-Louis Guinand (de fr) (20 April 1748, La Sagne — 13 February 1824, Les Brenets [12] [13] [14] [15] [16] [17] ) was a Swiss [18] [19] [20] [21] [22] who in the late 1700s came up with a breakthrough for making better quality and larger glass, and in time went on to teach a young Fraunhofer at Joseph von Utzschneider's (1763-1840 [23] ) glassworks, and eventually started his own optical glass works. [24] Guinand would supply glass for the Paris Observatory telescopes and also Cauchoix. [24]
Joseph Ritter von Fraunhofer was a German physicist and optical lens manufacturer. He made optical glass, an achromatic telescope, and objective lenses. He also invented the spectroscope and developed diffraction grating. In 1814, he discovered and studied the dark absorption lines in the spectrum of the sun now known as Fraunhofer lines.
A refracting telescope is a type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spyglasses and astronomical telescopes but is also used for long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece.
Andrew Graham, born in Irvinestown County Fermanagh, Ireland, was an Irish astronomer, orbit computer and discoverer of the asteroid 9 Metis.
Sir James South FRS FRSE PRAS FLS LLD was a British astronomer.
The Dunsink Observatory is an astronomical observatory established in 1785 in the townland of Dunsink in the outskirts of the city of Dublin, Ireland.
A comet seeker is a type of small telescope adapted especially to searching for comets: commonly of short focal length and large aperture, in order to secure the greatest brilliancy of light. This style of telescope was used to discover the asteroid 9 Metis in 1848.
The Vienna Observatory is an astronomical observatory in Vienna, Austria. It is part of the University of Vienna. The first observatory was built in 1753–1754 on the roof of one of the university buildings.
Grubb Parsons was a historic manufacturer of telescopes, active in the 19th and 20th centuries. They built numerous large research telescopes, including several that were the largest in the world of their type.
Thomas Grubb was an Irish optician and founder of the Grubb Telescope Company.
The Norman Lockyer Observatory, the Lockyer Technology Centre, and the Planetarium, is a public access optical observatory 1 mile (1.6 km) east of Sidmouth, East Devon in South West England. It houses a number of historical optical telescopes, including the Lockyer Telescope, and is operated by Norman Lockyer Observatory Society (NLOS).
Markree Castle is a castle located in Collooney, County Sligo, Ireland. It is the ancestral seat of the Cooper family, partially moated by the River Unshin. Today it is a small family-run hotel.
Great refractor refers to a large telescope with a lens, usually the largest refractor at an observatory with an equatorial mount. The preeminence and success of this style in observational astronomy defines an era in modern telescopy in the 19th and early 20th century. Great refractors were large refracting telescopes using achromatic lenses. They were often the largest in the world, or largest in a region. Despite typical designs having smaller apertures than reflectors, great refractors offered a number of advantages and were popular for astronomy. It was also popular to exhibit large refractors at international exhibits, and examples of this include the Trophy Telescope at the 1851 Great Exhibition, and the Yerkes Great Refractor at the 1893 World's Fair in Chicago.
Robert-Aglaé Cauchoix was a French optician and instrument maker, whose lenses played a part in the race of the great refractor telescopes in the first half of the 19th century.
Edward Joshua Cooper was an Irish landowner, politician and astronomer from Markree Castle in County Sligo. He sat in the House of Commons of the United Kingdom from 1830 to 1841 and from 1857 to 1859, but is best known for his astronomy, and as the creator of Markree Observatory.
The Greenwich 28-inch refractor is a telescope at the Royal Observatory, Greenwich, where it was first installed in 1893. It is a 28-inch ( 71 cm) aperture objective lens telescope, otherwise known as a refractor, and was made by the telescope maker Sir Howard Grubb. The achromatic lens was made Grubb from Chance Brothers glass. The mounting is older however and dates to the 1850s, having been designed by Royal Observatory director George Airy and the firm Ransomes and Simms. The telescope is noted for its spherical dome which extends beyond the tower, nicknamed the "onion" dome. Another name for this telescope is "The Great Equatorial" which it shares with the building, which housed an older but smaller telescope previously.
The Sheepshanks Equatorial Telescope was a 6.7-inch (170 mm) aperture refracting telescope installed in 1838 at the Royal Observatory in Greenwich. The telescope was donated to the observatory by the astronomer Richard Sheepshanks. The telescope had a doublet objective lens made by Cauchoix of Paris. Originally it was mounted on a clockwork driven equatorial mounting by the Grubb Telescope Company on a stone pillar.
Pierre-Louis Guinand (1748–1824) was a Swiss lens maker. who in the late 1700s came up with a breakthrough for making better quality and larger glass, and in time went on to teach a young Fraunhofer at Joseph von Utzschneider's (1763-1840) glassworks, and eventually started his own optical glass works. Guinand would supply glass for the Paris Observatory telescopes and also Cauchoix. He was a pioneer in the manufacture of optical glass for microscopes, telescopes, glasses and other optical instruments.
SPIE Proceedings (Large Lenses and Prisms - London, United Kingdom Tuesday 27 March 2001)
One of the first Swiss known to have endeavored in optics production, Pierre-Louis Guinand (1748—1824) was an amateur telescope maker. He was born in La Sagne in the state of Neuchâtel. As good quality flint glass was difficult to obtain at the time, Guinand put himself to the task of producing it. After painstaking searches and trials, he succeeded in producing flawless flint glass of large dimensions.
Between 1784 and 1790, Pierre Louis Guinand, a Swiss craftsman, taught himself the basic skills of glassmaking and began to experiment with optical glass.
Methods of making large disks of flint glass were discovered in the late 18th century by Pierre Louis Guinand (1748–1824), a Swiss optician, who became associated with the German optician and physicist Joseph von Fraunhofer.