A magnificent rendezvous between the planet of love and the bright orb of the Sun. The earliest recorded sightings of Venus appear in a tablet dating back to the 16th century BC.
With superlatives like these describing a transit of Venus, it is little wonder that astronomers are eagerly awaiting the next one — June 8, 2004.
In contrast to the indifference of 17th-century astronomers, interest in transits soared in the 1700s after English astronomer Edmond Halley proposed using them to determine the distance from the Earth to the Sun.
Despite being blown off course by a monsoon they reached the Indian coast, but passing ships notified them that Pondicherry had fallen. June 6th was a beautiful day in the Indian Ocean, and Le Gentil saw the entire transit, but from the deck of his pitching ship he could make no scientifically useful observations. Allerding recorded the 'black-drop' effect as the silhouette of Venus prepared to exit the Sun’s disk on December 9, 1874. Adapted from Observations of the Transit of Venus Made in New South Wales, by Henry C. Another hindrance to the 1761 observations was the unexpected discovery of the" black-drop effect." The key objective of most expeditions was to time the transit's internal (second and third) contacts — the precise moment when the limbs of Venus and the Sun barely touch.