Mrs Ples and the Andromeda Galaxy  

This year marks the 50th anniversary of the discovery, at Sterkfontein, of the fossilised skull which has become known as Mrs Ples.  This skull, which has ape-like and hominid features, was found by Dr Robert Broom in 1947 and is now housed in the Transvaal museum in Pretoria. Its age is reckoned at around 2.5 million years and it is the most complete specimen known of the species Australopithecus africanus.

The distance to the Andromeda galaxy has recently been revised and is now given as 2.5 million light years.  If you happened to be on a planet around one of the stars in this galaxy and you had a very large telescope and a nice clear night and you aimed it at our little planet Earth, you might be seeing right now Mrs Ples and her family walking around the Gauteng Highveld in an upright position, similar to present-day humans, but with the ability to grasp a branch with a thumb-like big toe.  You would be excused for thinking there was no intelligent life on that planet, only a bunch strange looking monkeys!!

Dr Francis Thackeray of the department of Palaeontology at the Transvaal museum has pointed out the link between Mrs Ples and the Andromeda galaxy.  He is of course no stranger to astronomy as his father, Dr A D Thackeray was director of the Radcliffe observatory in Pretoria and worked at SAAO and Sutherland after his retirement.

Another astronomical connection between Sterkfontein and astronomy has been noted by Dr Thackeray.  Amongst the bones found at the site are two that have been burnt by fire that has been determined, must have been at least 600 degrees.  Normal veld fires reach a temperature of only some 200 degrees, so these bones could have been roasted on a fire controlled by the inhabitants of the caves, as suggested by Dr. Bob Brain, about 1.0 - 1.5 million years ago. Our distant relative, Homo habilus was probably the guilty party.  This is the earliest known use of fire found on Earth.  Use of fire by Homo Sapiens led eventually to the development of the rocket engine and so to the little pathfinder now roving around the surface of Mars.

The Transvaal museum in Pretoria has  acquired two pieces of one of the 12 known meteorites that are thought to have originated on Mars. It is from a meteorite fall from Zagami in Nigeria and these are on display, together with a small piece of Moon rock which was given to the people of South Africa by the American president Richard Nixon after the Apollo moon landings.  In the same display area there is a very impressive collection of meteorites showing all the various forms of these rocks from outer space.

Although parts of the museum are closed at present because of building alterations, it is an exhibition well worth visiting.
 

Brian Fraser