Hartebeesthoek Radio Astronomy Observatory

The Hartebeesthoek Radio Astronomy Observatory (HartRAO) near Krugersdorp is the only major radio observatory in Africa. Originally built in 1961 by NASA and operated as Deep Space Station 51 until 1975, HartRAO was administered by the CSIR (Council for Scientific and Industrial Research) until 1991 when it became part of the former FRD. Today it is one of the national facilities of the NRF.

Astronomical research
HartRAO is devoted to research into radio wavelengths. Objects which emit radio waves in our own Milky Way Galaxy and other galaxies are studied. The radio emissions at 13cm wavelength from the whole southern sky have been mapped with the HartRAO telescope by a team from Rhodes University in Grahamstown, in order to study the faint outer reaches of our own Galaxy.

Super telescopes
Arrayed with telescopes on other continents, HartRAO forms part of a set of "super" telescopes able to see details hundreds of times finer than the best optical telescopes. Called Very Long Baseline Interferometry (VLBI), this technique enables the masers of our Galaxy to be pin-pointed and the fine details in jets from distant quasars (black holes in the hearts of distant galaxies) to be observed.

Studying the Earth
Quasars near the edge of the visible Universe form a fixed reference frame in space. By observing them with the VLBI technique the distances between the telescopes in the arrays can be measured to within a few centimetres. Due to its location, HartRAO is in great demand for these international experiments relating to the shape and behaviour of the Earth. The experiments are designed to follow the drift of the continents across the surface of the Earth, or the wandering of the Earth's North and South Poles. HartRAO now also forms the absolute reference point for the grid of national survey beacons. This will enable us to see whether global warming is causing sea levels to rise around our coasts. Conversely, we can now see whether the land itself is slowly rising or sinking.

Education

Academic staff and students from universities across South Africa carry out research projects and experiments at the observatory. Tours of the observatory are held for school classes and for the public, the aim of which is to increase the awareness and understanding of science and technology.

For further information on HartRAO, visit http://www.hartrao.ac.za