A monthly series on astronomy THE SIZK OF THE STARS by R. Hanbury Brown , F.R.S. Professor of Radio Astronomy, Manchester University
We know very little about the sizes of hot stars. Professor Hanbury Brown is preparing an experiment in Australia to measure the 200 brightest stars.
The diagram illustrates the principle of the experiment. The correlation between the photocell outputs decreases as D increases, in a way which depends on the star's diameter.
: previously broadcast in the BBC General Overseas Service

LESSON 14
Monday's recorded broadcast

Introduced by Roy Hay
Nothing at Stake: Frances Perry discusses the advantages of a non-staking border and suggests some suitable plants
Colourless Brightness: Noel Prock ter talks about the use of white flowers in the garden
Produced by John Greenslade

Introduced by Bill Hartley
Buying a Used Car. 2: Where and how to buy it. Advice by Robin Richards based on his experiences as a motor dealer
Roads Tomorrow: Ken Pitman of the Roads Campaign Council reports on road building programmes
It's my view ... : Ha'porths of tar. I. W. Rhys presents his views on the modern motor car
Produced by James Pestridge

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