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Venus

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History

The Persian polymath Abū ‘Alī Ibn Sīnā (980-1037 AD), known to early Western sources as Avicenna, records in one of his works, Compendium of the Almagest that ‘I say that I saw Venus as a spot on the surface of the sun’. The date and place of the observation are not given. This statement has been quoted subsequently by some Muslim astronomers, for example, by Naīr al-Dīn al-ūsī (1201–1274 AD). A transit of Venus indeed took place in Ibn Sīnā’s time, on 24 May 1032 AD (Julian). Did Ibn Sīnā see this transit or did he merely see a sunspot? The question was addressed by Bernard Goldstein in 1969 who concluded that “this transit may not have been visible where he lived”. The conclusion was based on the input provided to him by Brian Marsden who in turn used mathematical tables prepared by Jean Meeus in 1958 and gave sets of limiting terrestrial latitudes and longitudes from where the Contact I and II could be just observable.

Did Ibn Sina Observe the Transit of Venus of 1032 CE