Today's 2012 fun facts...

...Transits of Venus across the solar disk are rare events; only seven have taken place since the beginning of the 17th century. A detailed and accurate calculation by the Institut de Mécanique Céleste et de Calcul des Éphémérides (IMCCE) in Paris shows that there are exactly 82 Venus Transits between the years -3000 (BC) and 3000, that is, over a span of 6 millennia.

The first of these took place on November 17, -2970, and the last one will happen on June 14, 2984. If you are interested in more details, you may consult the extensive table ("Canon of Transits") on the comprehensive CD-ROM ( "Les Rendez-Vous de Vénus" ) that was produced by the Paris Observatory and also contains more than 10,000 fascimile pages of historical documents related to transit expeditions and observations. Look here for a brief description (Word) with some examples of the pages. It is on sale at EDP Sciences .

The next Venus Transits will take place in June 2012.

(click map to enlarge)