(Image: Paul McDevitt)
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Some numerology of astronomy
WHAT might be the hidden significance of the number 187.5? We reported that a measure of the delay between the arrival of low- and high-frequency components of mysterious bursts of radio waves comes in exact multiples of 187.5 (4 April, p 8). Chris Conklin immediately wrote to point out that 1.875 is “the smallest positive solution of cos(x)cosh(x) = –1″ and appears in the formula for calculating the frequency of a crystal oscillator from its size and properties. But the link to quartz clocks seems circumstantial…
