On Wednesday 6 June 2012 we had the opportunity to observe a spectacular, rare planetary alignment. Beginning just after 8 am AEST, the inner planet Venus crossed in front of the Sun. Such "transits" occur in groups of two, separated by 8 years (the previous one was in 2004). The next pair of transits will not happen until December 2117.
Transits of Venus are particularly relevant to Australia — Captain Cook's 1770 landing here followed a successful attempt to observe the 1769 transit from Tahiti. The objective was to obtain measurements of the transit from widely-separated parts of the Earth, from which the size of the solar system could be deduced.
Monash astronomers from the Schools of Physics and Mathematical Sciences, along with Monash Science Centre staff and Monash's In2Science coordinator hosted an observing session on Clayton campus for passersby to safely view the transit.
While the dawn sky was somewhat patchy with low cloud, a handful of early birds were thrilled when the Venus transit commenced and the clouds evaporated into a perfect cloudless blue sky. Once the sun rose, the telescopes were relocated to an area adjacent to the Physics buildings and the historic event-the last for another 105 years- was able to be witnessed by well over 600 staff, students and visitors.