Astronomical History


PROXIMA - the Nearest Star (other than the Sun!) (2008).

History of Alpha and Proxima Cen discoveries. Please click on link to get to description page.

Revolutionaries of the Cosmos, the Astro-Physicists (2006).

Biographies of Galileo, Newton, Wm. Herschel, Huggins, Hale, Eddington, Shapley and Hubble. Please click on link to get to description page.

Victorian Telescope Makers - the Lives and letters of Thomas and Howard Grubb (1997). Please click on link to get to description page.

From 1830 to about 1918, Thomas and Howard Grubb operated one of the world's leading telescope manufacturing businesses in the Dublin suburb of Rathmines.

The Royal Observatory at the Cape of Good Hope; History and Heritage (2015). Please click on link for more information.


The Story of the Radcliffe Telescope, QJRAS, 30, 33-58, 1989 (Available from the NASA ADS service).

The Radcliffe 74-inch in Pretoria, South Africa, used for the first time in 1948, was for several years the largest telescope in the Southern hemisphere and one of the largest in the world - after the 200-inch Palomar (also 1948), the 100-inch Hooker (1918), the 82-inch McDonald (1939) and the 74-inch David Dunlap instrument in Toronto (1935). The history of its construction is traced through correspondence files preserved at SAAO.

Beginnings of Astronomical Photography at the Cape, MNASSA, 48, 117-122, 1989 (pdf, 8pp, 141kB).

On October 4, 1882, an amateur photographer named William Simpson, of Aberdeen in the Cape, sent a photograph he had taken of the great comet of that year to David Gill. This stimulated the latter to a series of steps leading up to the Cape Photographic Durchmusterung. MNASSA, 48, 29-34, 1989 (pdf, 6pp, 160kB). Concerns the first photographic refractor constructed for Gill by Grubb. This was made by Grubb and financed by James Nasmyth. It incorporated a plateholder designed by Gill, the design of which was used for the later 'Astrographic' refractors made by Grubb.

The Discovery of the Nearest Star, MNASSA, 66, 244-262, 2007

In the 1830s, the double star Alpha Centauri was the subject of the first successful stellar parallax measurement. For almost 80 years it remained the nearest star known. However, in 1915, at the Union Observatory in Johannesburg, R.T.A. Innes found a faint object near Alpha Cen with a similar proper motion. Its parallax was measured over the following two years by J.G.E.G. Voute at the Cape and by Innes himself. The latter, on the basis of inadequate data, declared it to be closer than Alpha and named it 'Proxima Centaurus'. The first statistically significant data that indicated it truly is the nearest star were published in 1928 by H.L. Alden, based on observations obtained at the Yale Southern Station in Johannesburg. Discordant results continued however to appear until 1966. The measurements made by the Hipparcos astrometric satellite appear to have established its proximity beyond question.

Andrew David Thackeray and the Radcliffe Observatory, Pretoria, Trans. Roy. Soc. South Africa, 64, 2009 (pdf, 149kB)

An invited article on the late Andrew David Thackeray and the Radcliffe Observatory, Pretoria, on the occasion of the International Year of Astronomy 2009.

The Royal Observatory, Cape of Good Hope, a Valuable Cultural Property , published in "Cultural Heritage of Astronomical Observatories, from Classical Astronomy to Modern Astrophysics", Proceedings of the International Icomos Symposium in Hamburg, October 14-17, 2008. Monuments and Sites XVIII, Icomos, 2010 (pdf, 220kB). A presentation about the Royal Observatory, Cape of Good Hope, in cultural-historical terms.

Astronomical Museum please click for description (pdf, 16pp, 400kB)

Attached to the McClean (Victoria) telescope at SAAO in Cape Town is a small laboratory originally intended for spectroscopic investigations complementary to work undertaken at the telescope. During the '70s and '80s it was used by me as an infrared laboratory. After the move to the new Technical Building, I set up a museum of small instruments in the laboratory. These illustrate some of the activities of the former Royal Observatory and the early days of the present SAAO. R.M. Catchpole re-furbished the lobby and encased the ancient hydraulic floor pump in perspex. To this were added, by E. Lastovica, graphic displays of old illustrations and boards illustrating the present-day interests of the Observatory.

The Grubb Contribution to Telescope Technology (Venice 2009) (.pdf file, 12pp, 3.4MB).

Presentation at "Astronomy and its Instruments before and after Galileo", Venice, 2009. Eds. Pigatto, L \& Zanini, V., Joint Symposium IAU and INAF Astronomical Observatory of Padova. CLEUP, Padova, 2010.

For almost 100 years the Grubbs of Dublin, Ireland, were famous for the telescopes they supplied to observatories worldwide. Two generations of the family dominated this unusual enterprise. Their success can be attributed to innovative engineering, often introduced at the urging of their most demanding customers.

Astrographic Telescope at the Royal Observatory, Cape (MNASSA, 71, 113, 2012. pdf file, 8pp).

The Astrographic was one of several produced by the Grubb Company for the Carte du Ciel project. The Cape Zone was from declination -40 to -52 degrees. Among other things, it was used by McClean for the discovery of Oxygen in certain stars, by Voute for work on the parallax of Proxima Cen, and by Cousins for Fabry phototometry and for early photoelectric photometry.

J.K.E. Halm (1865-1944) (MNASSA, 73, 2014. 10pp pdf file, 8pp).

Halm was Chief Assistant at the Royal Observatory, Cape. He was a pioneer of stellar dynamics and the first person to suggest the mass-luminosity releation in stars. He also studied reciprocity failure in photographic plates and was the first to study the colour dependence of interstellar absorption. Not mentioned in this paper was the fact that he was the first to understand the cause of what are now called P-Cygni line profiles (while an Assistant at the Royal Observatory, Edinburgh).

The Franklin-Adams Telescope (MNASSA, 74, 127, 2014. 9pp pdf file).

The Franklin-Adams telescope was a wide-angle instrument used in both hemispheres to make a the first photographic atlas of the whole sky. It was used by Innes for the discovery of Proxima Cen. It still exists at Toppieshoek.

Early Days at the SAAO (MNASSA, 60, 13, 2001. 7pp pdf file).

Some somewhat irreverent reminiscences about the early days of SAAO when Sir Richard Woolley was in charge.

Astronomical History Symposium 2005

Organized under the auspices of the Astronomical Society of Southern Africa, this symposium brought together people interested in the history and pre-history of astronomy as it relates to Africa. Proceedings published in African Skies, No. 11, July 2007.


David Gill and His Work (pdf, 3MB). In SAAO Museum.

Astronomers at the Royal Observatory, Cape of Good Hope (pdf, 2.3MB). In SAAO Museum.

The Royal Observatory, Cape of Good Hope: a Cultural Treasure (pdf, 1.2MB). In SAAO Museum.

A somewhat unfinished poster concerning buildings of the Royal Observatory, Cape, that no longer exist, (pdf, 8.1MB).

Finding celestial positions, one of the main tasks of the Royal Observatory (pdf, 3.5MB).

The McClean telescope of the Royal Observatory, Cape. (pdf, 2.7MB).

The SAAO and its Astronomical Museum (pdf, 950kB). The photographic exhibition from the 175th Anniversary is no longer on display.

Tercentenary of the birth of Nicolas-Louis de La Caille (1713-2013) (pdf, 5.3MB). In SAAO Museum.

Determining the time and distributing it - one of the main tasks of the Royal Observatory, Cape (pdf, 1.1MB). In SAAO Museum.

The Visitor Programme at SAAO, Cape Town (pdf, 1.4MB). This was a contribution to the CAP 2010 conference, Cape Town 2010 [Communicating Astronomy to the Public].

Mini-posters of Royal Observatory telescopes:

Gill Reversible Transit Circle (pdf, 2.2MB)

Photoheliograph and dome (pdf, 380kB). Former dome of the Merz 7.5-in telescope that is now the guider of the 18-inch.

Airy Transit Circle (pdf, 930kB). Was located in Main Building.

Astrographic Telescope (pdf, 580kB).

McClean Telescope (pdf, 180kB).

18-inch/heliometer/Merz (jpg 41KB)

6-inch (jpg 63KB)


Royal Observatory (General) (pdf. 2.9MB)

Astronomical Museum of Royal Observatory (pdf. 3.1MB)

See also the Thomas and Howard Grubb Telescope List and the Grubb Parsons Telescope List

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