page_title: Arthur Bleksley
section_title: Education and career
hierarchical_section_title: Arthur Bleksley / Education and career
caption_attribution_description: English: This Hubble image shows RS Puppis, a type of variable star known as a Cepheid variable. As variable stars go, Cepheids have comparatively long periods— RS Puppis, for example, varies in brightness by almost a factor of five every 40 or so days. RS Puppis is unusual; this variable star is shrouded by thick, dark clouds of dust enabling a phenomenon known as a light echo to be shown with stunning clarity. These Hubble observations show the ethereal object embedded in its dusty environment, set against a dark sky filled with background galaxies.
context_page_description: Arthur Edward Herbert Bleksley was a South African Professor of Applied Mathematics and an astronomer. Bleksley's early research involved the astrophysics and astronomy of variable stars. He encouraged science awareness in South Africa by publishing articles about science, by being on a popular radio show, and through his presentations at the Johannesburg Planetarium.
context_section_description: Bleksley was born in the Eastern Cape and attended the Outeniqua High School in George. After matriculation he studied at Stellenbosch University and graduated cum laude in 1927 and went on to obtain his M.Sc. in 1929, winning the Van der Horst Prize. In 1930 he joined the Solar Research Station run by the National Geographic Society and the Smithsonian Institution at Brukkaros, the caldera of an extinct volcano in South West Africa. American researcher William H. Hoover and his colleague Frederick Atwood Greeley, ran an observatory on the mountain from 1926 to December 1931, collecting solar radiation data so as to find a correlation with the earth's weather. To this end detailed observations were made of the Solar Constant. High-altitude observatories were set up at various locations - Mount Montezuma in Chile, initially at Mount Harqua Hala in Arizona (later moved to Table Mountain in California) and lastly Mount Brukkaros, a site selected by Charles Greeley Abbot, and later moved to Mount St. Katherine on the Sinai peninsula. The Brukkaros observatory consisted of a 10m deep tunnel in the flank of the mountain. A solar telescope or coelostat at the mouth of the tunnel passed sunlight to a spectrograph, an Ångström compensation pyrheliometer and a bolometer further in.
  In 1932 Bleksley was appointed as Junior Lecturer in the Department of Applied Mathematics at the University of Witwatersrand, eventually becoming head of the department. Whilst there he worked on and completed his doctoral thesis A Statistical and Analytical Study of the Phenomenon of Long-period Stellar Variability. Bleksley developed a mathematical model of radially pulsating stars, and the observations for the Cepheid variable stars and long-period variable stars compared favourably with his model's predictions. During this period he took sabbatical leave and studied under Sir Arthur Eddington at Cambridge, Professor Hans Ludendorff of the Astrophysical Observatory at Potsdam and Ejnar Hertzsprung at Leiden. He was President of the Astronomical Society of Southern Africa in 1948/49 and one of about 100 people who attended the founding of the SA Institute of Physics on 7 July 1955.
caption: RS Puppis is one of the brightest known Cepheid variable stars in the Milky Way galaxy; image, Hubble Space Telescope
exif: {"Image ImageDescription": "This Hubble image shows RS Puppis, a type of variable star known as a Cepheid variable. As variable stars go, Cepheids have comparatively long periods \u2014 RS Puppis, for example, varies in brightness by almost a factor of five every 40 or so days. RS Puppis is unusual; this variable star is shrouded by thick, dark clouds of dust enabling a phenomenon known as a light echo to be shown with stunning clarity. These Hubble observations show the ethereal object embedded in its dusty environment, set against a dark sky filled with background galaxies."}