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102 25 The August Perseids
remained until the approach of dawn, when we adjourned indoors to refresh ourselves with drinks which were rather more potent than coffee. The end of an enjoyable evening.
Whathadweachieved?Scientificallynotagreatdeal,thoughroutineobservations are always useful; our main point was that we had spoken to a large audience of around a million people, some of whom went outside and watched a spectacle which they would otherwise have missed. That in itself, I feel, justified our special programme. Of course, the Perseids will be with us again next year, but in 2008 the conditions will not be nearly so favourable, as meteor watchers will have to contend with strong moonlight.
Finally, spare a thought for Comet Swift-Tuttle, responsible for it all. It was not seen for many years after 1862, and calculations indicated that although it had been missed at several intervening returns, it should be back in 1981. Careful searches gave negative results, and I thought that it had simply been overlooked. John Mason disagreed; he believed that the orbit had been wrongly worked out, so that the real date of the next perihelion passage would be early in the 1990s. We had a modest bet about this (a bottle of Irish Whisky, I recall) and I was confident – until 1992, when the comet turned up. The period is now known to be 135 years, Swift-Tuttle has not been conspicuous lately, but a good deal will be heard about it in the twenty-second century, when it will pass alarmingly close to us. Wait for an end-of-the world scare then – but don’t blame the Perseids!
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