2012 programme

Sat 7th 12:00-12:30

Viewing Venus transits since 1639

Ian Sullivan


Since the first viewing in 1639, five transits of the planet Venus across the Sun have occurred, and we are about to witness another in June 2012. Like eclipses, these events provide an exciting spectacle of nature for all, but they have been one of the earliest examples of scientific cooperation between nations in an attempt to use observation data to estimate the solar parallax or Earth - Sun distance. From 1761 to 1882 for each transit, astronomers representing many nations travelled the world to remote locations. Amateurs with lesser equipment have also participated, and the events have provided great learning experiences. This paper is an overview of what has transpired including expectations, some disappointment, and prospects.