LETTER : Perfect viewing of a total eclipse

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The Independent Online
From Mr John Wright

Sir: I read with interest your articles about the recent total eclipse in India, because I was lucky enough to see one under perfect conditions in February 1953 in the northern Sudan. It was at 11am and, in February, clear skies were so guaranteed that four years earlier astronomers started writing to me in the Survey Department because they wished to come to observe it.

When it occurred, I was stationed 200 miles north of Khartoum; and as the local astronomical expert I had told the British and Sudanese there about its causes and what to expect, using white and black ping-pong bats, a lamp and a tennis ball etc.

On the day, we moved out into the desert to be on the path of totality and climbed a small hill. Two interesting phenomena occurred. First, which I had not foreseen, the dappled sunlight caused by chinks in a bush on the hill (which are of course elliptical images of the sun) turned into crescents as the moon advanced across it.

Secondly, which I had read about and was expecting, the tiny spot of light at the edge of the sun just before and after totality acted like a star and twinkled. This meant that the edge of the shadow was not sharp but a series of shadow bands; and these raced towards us across the desert at a thousand miles an hour as the Earth rotated under the images of the sun and moon. It was an awe-inspiring sight; and of course the shadow bands came from the East; so I was puzzled by your description of the eclipse moving south-eastwards in some of your articles about it.

Yours faithfully,

John Wright

West Wittering, West Sussex

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