A RARE astronomical event is due to take place on June 6, and you can find out all about it in a talk to be presented at Ballina library on May 17.
The Transit of Venus will be the topic for the 10am presentation by Paul Brunton, the curator of the Mitchell Library, State Library of NSW.
The tranist of Venus occurs when the planet Venus travels between the sun and the Earth.
Mr Brunston said the event would last six-and-a-half hours. The last transit was in 2004.
"Usually, two transits occur within eight years of each other and then not again for more than 100 years," Mr Brunston said.
The transit of Venus was first observed in 1639.
By recording, from various locations, the time taken for the transit, it is possible to calculate the distance of the Earth from the sun, providing information about stars and planets useful in naviagtion.
In 1769, James Cook observed the transit from Tahiti before heading south to New Zealand and Australia.