Andrew Ainslie Common
Encyclopedia
Andrew Ainslie Common FRS (1841 – 1903) was an English
amateur astronomer best known for his pioneering work in astrophotography
.
on August 7, 1841. His father, Thomas Common, a surgeon known for his treatment of cataract, died when Andrew was a child forcing him to go early into the world of work. In the 1860s he teamed up with an uncle in the sanitary engineering firm of Matthew Hall and Company. He married in 1867. In 1890 he retired from Matthew Hall. Andrew Ainslie Common died of heart failure June 2, 1903.
.
In 1876 Common became a Fellow of the Royal Astronomical Society
. About this time he also moved to Ealing
outside London
where he would live for the rest of his life operating an astronomical observatory from back yard of his house. Common realized he would need very large telescopes to gather enough light to record the images of stars photographically so he began building a series of ever larger Newtonian reflecting telescopes
using the then new technology of silver coated glass mirrors. For the first of these, a telescope of his own design constructed in 1876, he tried to grind and polish his own 17 inch mirror but gave up on the idea and ordered an 18 inch (46 cm) mirror from the optical firm of George Calver of Chelmsford. In 1877 and 1878 he published several articles on his visual observations of the satellites of Mars and Saturn.
The 36-inch reflector
In 1879 he bought a new 36 inches (914.4 mm) mirror from Calver to mount in a larger Newtonian reflecting telescope he was building. He used it to make further observations of satellites of Mars and Saturn, and was able to see Saturn’s moon Mimas
and show that the ephemeris of its orbit was incorrect. With this instrument he also obtained a photograph of a comet in 1881, C/1881 K1. His most notable work with this telescope were the long time exposures he made of the Orion Nebula
between 1880 and 1884. His 1883 photograph of that nebula for the first time showed films ability to record stars and other features invisible to the human eye. Common noted of his own photographs that:
These pictures earned Common the Gold Medal of the Royal Astronomical Society
in 1884. Common eventual sold the 36 reflector to British
politician Edward Crossley
who gave it to Lick Observatory
in 1895, becoming the Crossley telescope
at that observatory.
The 60-inch reflector
In 1885 Common embarked on building a 60-inch (152 cm) Newtonian reflecting telescope. He chose to buy the raw glass blank and do the grinding and polishing himself. The first mirror he made performed poorly, showing an elliptical deformation of the stars, causing him to fabricate a second mirror in 1890. After a near fall from the high staging needed to reach the Newtonian focus of the telescope Common decided to convert the telescope to a Cassegrain
configuration for safer use. To avoid having to bore a hole in the 60 inch primary mirror
he mounted a diagonal flat mirror just in front of it to bring the image out to a focus at the lower side of the telescope. He was not satisfied with how this configuration worked and that, combined with his attention being diverted to other projects and the ever more light polluted skies west of London, meant the telescope fell into disuse. After Common’s death the telescope with its two 60 inch mirrors and other secondary optics was purchased from his estate and installed at the Harvard College Observatory
. In the 1933 the primary mirror was re-figured
and a new mount built. It was then set up as the 1.5 meter Boyden-UFS reflector (also called the "60 inch Rockefeller") at Boyden Observatory
in South Africa
.
England
England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...
amateur astronomer best known for his pioneering work in astrophotography
Astrophotography
Astrophotography is a specialized type of photography that entails recording images of astronomical objects and large areas of the night sky. The first photographs of an astronomical object were taken in the 1840s, but it was not until the late 19th century that advances in technology allowed for...
.
Biography
Common was born in Newcastle Upon TyneNewcastle upon Tyne
Newcastle upon Tyne is a city and metropolitan borough of Tyne and Wear, in North East England. Historically a part of Northumberland, it is situated on the north bank of the River Tyne...
on August 7, 1841. His father, Thomas Common, a surgeon known for his treatment of cataract, died when Andrew was a child forcing him to go early into the world of work. In the 1860s he teamed up with an uncle in the sanitary engineering firm of Matthew Hall and Company. He married in 1867. In 1890 he retired from Matthew Hall. Andrew Ainslie Common died of heart failure June 2, 1903.
Work in astronomy
Although Common’s professional career was in the field of sanitary engineering, he is most noted for the work he did as an amateur in the field of astronomy. As a child Andrew showed interest in astronomy. At age 10 his mother borrowed a telescope for him to use from a local doctor. He returned to astronomy in his 30’s when he took up experimenting with gelatin plate photography of the moon and plants with 5.5 inch refracting telescopeRefracting telescope
A refracting or refractor 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 spy glasses and astronomical telescopes but is also used for long focus camera lenses...
.
In 1876 Common became a Fellow of the Royal Astronomical Society
Royal Astronomical Society
The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...
. About this time he also moved to Ealing
Ealing
Ealing is a suburban area of west London, England and the administrative centre of the London Borough of Ealing. It is located west of Charing Cross and around from the City of London. It is one of the major metropolitan centres identified in the London Plan. It was historically a rural village...
outside London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...
where he would live for the rest of his life operating an astronomical observatory from back yard of his house. Common realized he would need very large telescopes to gather enough light to record the images of stars photographically so he began building a series of ever larger Newtonian reflecting telescopes
Newtonian telescope
The Newtonian telescope is a type of reflecting telescope invented by the British scientist Sir Isaac Newton , using a concave primary mirror and a flat diagonal secondary mirror. Newton’s first reflecting telescope was completed in 1668 and is the earliest known functional reflecting telescope...
using the then new technology of silver coated glass mirrors. For the first of these, a telescope of his own design constructed in 1876, he tried to grind and polish his own 17 inch mirror but gave up on the idea and ordered an 18 inch (46 cm) mirror from the optical firm of George Calver of Chelmsford. In 1877 and 1878 he published several articles on his visual observations of the satellites of Mars and Saturn.
In 1879 he bought a new 36 inches (914.4 mm) mirror from Calver to mount in a larger Newtonian reflecting telescope he was building. He used it to make further observations of satellites of Mars and Saturn, and was able to see Saturn’s moon Mimas
Mimas (moon)
Mimas is a moon of Saturn which was discovered in 1789 by William Herschel. It is named after Mimas, a son of Gaia in Greek mythology, and is also designated Saturn I....
and show that the ephemeris of its orbit was incorrect. With this instrument he also obtained a photograph of a comet in 1881, C/1881 K1. His most notable work with this telescope were the long time exposures he made of the Orion Nebula
Orion Nebula
The Orion Nebula is a diffuse nebula situated south of Orion's Belt. It is one of the brightest nebulae, and is visible to the naked eye in the night sky. M42 is located at a distance of and is the closest region of massive star formation to Earth. The M42 nebula is estimated to be 24 light...
between 1880 and 1884. His 1883 photograph of that nebula for the first time showed films ability to record stars and other features invisible to the human eye. Common noted of his own photographs that:
- "although some details are lost in the enlargement, sufficient remains to show that we are approaching the time where a photograph will give us the means to recording in its own inimitable way the shape of a nebula and the relative brightness different parts, in a better manner than the most careful hand drawing”.
These pictures earned Common the Gold Medal of the Royal Astronomical Society
Royal Astronomical Society
The Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...
in 1884. Common eventual sold the 36 reflector to British
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
politician Edward Crossley
Edward Crossley
Edward Crossley was an English businessman, Liberal Party politician and astronomer.-Biography:Edward Crossley was the eldest son of Joseph Crossley J.P., of Broomfield, Halifax, Yorkshire, of the Crossley carpets dynasty. He inherited his family's carpet manufacturing business from his father...
who gave it to Lick Observatory
Lick Observatory
The Lick Observatory is an astronomical observatory, owned and operated by the University of California. It is situated on the summit of Mount Hamilton, in the Diablo Range just east of San Jose, California, USA...
in 1895, becoming the Crossley telescope
Crossley telescope
The Crossley telescope is an reflecting telescope located at Lick Observatory in the U.S. state of California.-History:Given to the observatory in 1895 by British politician Edward Crossley, it was rebuilt from the ground up as it was on a very flimsy mounting. It is still being used today in the...
at that observatory.
The 60-inch reflector
In 1885 Common embarked on building a 60-inch (152 cm) Newtonian reflecting telescope. He chose to buy the raw glass blank and do the grinding and polishing himself. The first mirror he made performed poorly, showing an elliptical deformation of the stars, causing him to fabricate a second mirror in 1890. After a near fall from the high staging needed to reach the Newtonian focus of the telescope Common decided to convert the telescope to a Cassegrain
Cassegrain reflector
The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas....
configuration for safer use. To avoid having to bore a hole in the 60 inch primary mirror
Primary mirror
A primary mirror is the principal light-gathering surface of a reflecting telescope.-Description:The primary mirror of a reflecting telescope is a spherical or parabolic shaped disks of polished reflective metal , or in later telescopes, glass or other material coated with a reflective layer...
he mounted a diagonal flat mirror just in front of it to bring the image out to a focus at the lower side of the telescope. He was not satisfied with how this configuration worked and that, combined with his attention being diverted to other projects and the ever more light polluted skies west of London, meant the telescope fell into disuse. After Common’s death the telescope with its two 60 inch mirrors and other secondary optics was purchased from his estate and installed at the Harvard College Observatory
Harvard College Observatory
The Harvard College Observatory is an institution managing a complex of buildings and multiple instruments used for astronomical research by the Harvard University Department of Astronomy. It is located in Cambridge, Massachusetts, USA, and was founded in 1839...
. In the 1933 the primary mirror was re-figured
Figuring
Figuring is the process of final polishing of an optical surface to remove imperfections or modify the surface curvature to achieve the shape required for a given application.-Types of figuring:...
and a new mount built. It was then set up as the 1.5 meter Boyden-UFS reflector (also called the "60 inch Rockefeller") at Boyden Observatory
Boyden Observatory
Boyden Observatory is a South African astronomical research observatory and science education centre.-History:The observatory was originally founded in 1889 by the Harvard University at Mount Hardvard near Lima, Peru, but relocated to Arequipa, Peru in October 1890.Significant work done at Arequipa...
in South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
.
Other projects
Andrew Ainslie Common experience with optical fabrication lead him to work on gun-sights and telescopes for the army and navy. He also pioneered techniques to produce large optical flat mirrors.Selected honours and awards
- Gold Medal of the Royal Astronomical SocietyGold Medal of the Royal Astronomical Society-History:In the early years, more than one medal was often awarded in a year, but by 1833 only one medal was being awarded per year. This caused a problem when Neptune was discovered in 1846, because many felt an award should jointly be made to John Couch Adams and Urbain Le Verrier...
(1884)
- Fellow of the Royal Society (1885)
- President of the Royal Astronomical SocietyRoyal Astronomical SocietyThe Royal Astronomical Society is a learned society that began as the Astronomical Society of London in 1820 to support astronomical research . It became the Royal Astronomical Society in 1831 on receiving its Royal Charter from William IV...
(1895 – 1896)