How cool! Lots of Astronomical excitement happening!
The next transit of Venus will occur on 5 and 6 June 2012, and will be the last Venus transit this century; the prior transit took place on 8 June 2004. After 2012, the next transits of Venus will be in December 2117 and December 2125.
Venus transits are historically of great scientific importance as they were used to gain the first realistic estimates of the size of the Solar System. Observations of the 1639 transit, combined with the principle of parallax, provided an estimate of the distance between the Sun and the Earth that was more accurate than any other up to that time. In addition, the June 2012 transit will provide scientists with a number of other research opportunities, particularly the refinement of techniques to be used in the search for exoplanets.