|The Restored 6-foot Rosse Telescope as it appears today.
photo courtesy of
The Earls of Rosse and Birr Castle Observatory: Birr Castle Observatory was one of the most extraordinary scientific centres ever to have been established anywhere in the world. It has been made doubly remarkable by reason of its recent restoration, though as a museum and tourist attraction rather than a working observatory.
The Observatory was founded in 1827 at his estate at Birr, Co. Offaly (about 80 miles west of Dublin) by William Parsons, heir to the Second Earl of Rosse and who later became the Third Earl. Finding himself, at the age of 27, in the possession of leisure, extensive means and great mechanical ability, he decided to devote himself to the construction of large telescopes. These were all reflectors, involving the use of "speculum metal", an alloy of copper and tin. A 3- foot (0.915m) instrument was completed in 1839, followed by a 6-foot (1.83m), the "Leviathan of Birr" in 1845. This instrument became world famous and remained the largest telescope in the world until dismantled in the early part of the 20th century.
Engineering constraints dictated that the 6-foot be mounted between two walls, which had the effect of restricting its use to areas of sky close to the meridian. Nevertheless the instrument, under the Third Earl and his son, the Fourth Earl, was responsible for many discoveries, the most notable of which was the spiral structure of many galaxies (at that time included under the general title of "nebulae").
A pioneering experiment, carried out in 1868 with the 3-foot instrument, was the measurement of the temperature of the moon. The drop in the moon's temperature during lunar eclipses was also accurately measured.
Coated aluminium, rather than speculum metal, is used for the recently restored instrument. The original speculum mirror may be seen at the British Science Museum, South Kensington, London.
A lunar crater (in the Mare Nectaris, NE of Fracastorius) is named "Rosse", after the Third Earl.
Edward J. Cooper and Markree Castle Observatory:This observatory was founded on his estate near Collooney, Co Sligo by Edward J. Cooper in 1832. His interest in astronomy arose during childhood visits to the Rev. J.A. Hamilton, first director of Armagh Observatory.
In 1831, Cooper purchased a 13.5-inch (35.5 cm) lens from Cauchoix of Paris for his observatory. To this was added inter alia a 5-foot (1.5 m) transit telescope, a 3-foot (0.9 m) meridian circle a 4-inch (10 cm ) comet seeker and a transit clock. It is little wonder that the observatory was described at the Annual Meeting of the Royal Astronomical Society in 1851 as "the most richly furnished private observatory in existence"!
Apart from searches for comets, transit observations and planetary astronomy, the chief work carried out at Markree was the preparation of an extensive and accurate series of ecliptic star charts. The catalogue of these stars was published in Dublin over the period 1851 - 1856 in four volumes entitled "Catalogue of Stars near the Ecliptic Observed at Markree". The work contains the positions of 60,066 stars down to the 12th magnitude, of which only 8965 had previously been catalogued. The corresponding star charts were never published. As might be expected, some of the "stars" on the charts are not now to be found in the sky. They are probably asteroids that were not recognised as such at the time.
Having regard to the systematic work carried out at Markree, it is, perhaps, surprising that only one asteroid was discovered there. This was 9 Metis, discovered by Cooper's assistant, Andrew Graham, on 25 April 1848. Cooper named the asteroid Metis from the Greek word meaning a prudent plan or counsel.
Cooper died in 1863 but the observatory continued to be operated intermittently until 1902, when it closed except for meteorological observations.
|Daramona Observatory about 1900.
photo from the archives of
William E. Wilson and Daramona Observatory: William E. Wilson, high sheriff for the county, founded this observatory on his father's estate at Streete, Co. Westmeath, in 1871. His interest in astronomy derived from a visit to view a total eclipse of the sun on 22 December, 1870 at Oran, Algeria, when he was nineteen years old.
Wilson's first instrument was a 12-inch (30.5 cm) reflector made by Howard Grubb of Dublin. This was followed in 1881 by one of 2 feet (61 cm) diameter. Electrical controls were added to this second instrument in 1891 in order to facilitate astronomical photography. With this equipment he made photographic observations of stellar transits as well as making many superb photographs of clusters and nebulae. In 1902 he developed a method of determining the temperature of the solar photosphere by balancing the amount of solar radiation against the radiation from an electrically heated strip of platinum. The temperature obtained (5900K) was very close to the true value. His scientific work was recognised by his election as Fellow of the Royal Society in 1896 and by the conferring of an honorary degree of Doctor of Science by Dublin University in 1901.
Wilson died in 1908 and the observatory then closed.
Dr Wentworth Erck and Sherrington Observatory:
Dr Wentworth Erck and Sherrington Observatory:Dr Erck was the son of an Ecclesiastical Commissioner for Ireland and, after studying for the bar, became magistrate for Co Wicklow. He developed an interest in astronomy in his early youth and decided to set up an observatory at his home at Sherrington, Bray. This he equipped with a 7.5-inch (23 cm) refractor and a 15-inch (46 cm) reflector.
He used his equipment extensively, chiefly on the sun and planets. He has left records of the appearance of the sun's disc on a great number of days from 1869 to 1888. He appears to have been among the first to notice the movement of the Great Red Spot of Jupiter with respect to other features on the planet. He contributed extensively to contemporary scientific journals.
On his death in 1890 observations ceased at Sherrington. The 7.5-inch refractor appears to have passed into the hands of the Dublin observer William Monck. (See below.)
John Birmingham and Millbrook Observatory:Millbrook Observatory was founded by John Birmingham, a country gentleman residing near Tuam, Co Galway. Although his only equipment was a 4.5-inch (11 cm) refractor he achieved early success by the discovery of the [now recurrent] nova T Coronae Borealis in 1866. He discovered a variable star in Cygnus in 1881.
Starting in 1872 and acting on the suggestion of his English contemporary, the Rev. T. Webb, he undertook, from his own observations, a revision of Schjellerup's Red Star Catalogue. The project ended with the publication in 1877 of an expanded list of 658 red stars, incorporating observations by Schmidt, d'Arrest, Webb, Secchi and Herschel as well as his own.
In addition to his work on variable and red stars, he published papers on sunspots, meteor showers and the 1874 transit of Venus. On his death in 1884, work at the observatory ceased. A large feature on the moon (situated between Plato and the northern limb) is named after Birmingham.
William S. Monck and the Earlsfort Terrace (Dublin) Observatory:
William S. Monck and the Earlsfort Terrace (Dublin) Observatory:The only instrument contained in this observatory was a 7.5-inch refractor that appears to have been acquired from Sherrington. Son of the rector of Inistioge, Co Kilkenny, Monck had a distinguished career at Trinity College, Dublin. Although holding important posts in Dublin, he retained his interest in scientific matters and August 1892 found him engaged with Professor George Fitzgerald in making the first photoelectric observations of planets and stars. A plaque at 16 Earlsfort Terrace commemorates this pioneering achievement.
The experimental arrangement used was a selenium cell, one plate of which was connected to a quadrant electrometer and the other to earth. Light from the planet or star under observation could be cut off by a screen and it was thus possible to observe the effect of the incident light on the cell by noting the deflection of the electrometer needle when the screen was interposed and then removed.
Monck wrote extensively in astronomy, his chief interest being stellar classifications. In this he came close to anticipating by ten years the work of Hertzsprung in constructing the HR-diagram. Beside his writings, Monck found time to advocate the foundation of an association for amateur astronomers. His efforts bore fruit in 1890 with the formation in London of the British Astronomical Association, of which he was a founder member. His death, in 1915, resulted in the closing of the Earlsfort Terrace Observatory.
John E. Gore: Son of the Venerable John R. Gore, Archdeacon of Athenry, Co Galway, John E. Gore was born at Athlone in 1845. His father's house at Ballysadare, Co Sligo, was within a few miles of Markree Castle and it is probable that his interest in astronomy arose from visits to the observatory there. He spent much of his early manhood in the Public Works Department in India and on retiring from there in his early thirties devoted himself to the study of astronomy. He established an observatory, initially at Ballysadare and then at 3 Northumberland Road, Dublin, where he had lodgings. He never married.
Although possessed of only a 3-inch refractor and a pair of binoculars, he discovered the variability of several stars, including U Orionis, S Sagittae, W Cygni and X Herculis. He also produced a new catalogue of variables, containing 190 entries. He also concerned himself in the computation of the orbits of binary stars and in 1890 published a catalogue of all binary stars for which orbits had been determined. He wrote several books on astronomy and contributed numerous articles to the Monthly Notices of the Royal Astronomical Society. Like Monck, he was a founder member of the British Astronomical Association and was Director of the Variable Star Section for many years.
Gore died on 18 July 1910, after being knocked down by a jaunting car in Dublin's Grafton Street. His lodgings then passed to a tenant not interested in astronomy.
Isaac W. Ward: Born in Belfast on 13 September 1834, Isaac Ward lived at 22 Camden Street. He came from a noted Belfast family which farmed land where the Malone Golf Course is now located. He was among the foremost observers of the day, despite the fact that his sole observing instrument was a 4.3-inch refractor. According to David Beesley (c.f. below), his chief handicap was his own modesty, a trait that prevented his genius from being more widely appreciated. Beesley writes: "His brain was one that registers mathematical accuracy without effort: the keen vision, the cast-iron memory were all attributes of the highest, and had ambition ever lured him away from his native Belfast, greater aims and scope of work might have placed him in the ranks of the foremost scientific men of the day".
R. Proctor spoke of Ward as a man "of the keenest vision", a view that is borne out by all reports. The Rev. T. W. Webb in his "Celestial Objects for Common Telescopes" gives many instances of his marvellous acuity of vision, in that he was able to observe faint planetary satellites and split double stars with smaller apertures than anyone else. Webb refers to Ward no less than 43 times in his book, mostly in relation to his prowess in resolving double stars.
Ward's chief claim to fame lies in his observation of a supernova in the Andromeda Galaxy M 31 in 1885, an object that has since been given the name "S Andromedae". To be sure, the concept of supernovae had not yet been born at that time and there was no appreciation of the true nature of M 31 as a galaxy similar to our own. Ward observed the supernova on 19 August of that year near the nucleus of the galaxy, shining at an estimated magnitude 7. He was the first to observe it with the appreciation that it was a real object. It had been seen two days earlier by a Professor Gully at Rouen, France but he failed to recognise its significance, attributing it to a defect in a new telescope. The supernova brightened to magnitude 6 during the days following its discovery and then faded gradually to invisibility over the succeeding months.
Under the pen-name "Belfastiensis" Ward contributed to Belfast newspapers on various subjects and under the signature "Linea" to the "English Mechanic and World of Science". He was a member of the short-lived Ulster Astronomical Society (1890-1894) but appears not to have held any office in that body. He died on 11th October 1916 and is interred at Drumbeg Cemetery.