Total eclipses of the Sun are probably the most spectacular events in Nature. During the day the sky becomes dark, birds and animals become confused and suddenly the faint outer atmosphere of the Sun, the corona, snaps into view. Many avid eclipse watchers travel great distances to have the opportunity of seeing such a wonderful event. Among these keen eclipse watchers is the Sydney Observatory group that travelled to Easter Island earlier in 2010.
There are occasionally opportunities to view total eclipses of the Sun closer to home, from the Australian continent. Here we mention some past and some forthcoming ones.
A total eclipse was to be seen from Sydney soon after the arrival of the first Government Astronomer for NSW, Rev William Scott. The eclipse took place on 25 March 1857 in the early morning at around 6:47 am in present day AEST and lasted just under two minutes. Sensibly Scott travelled out to South Head light house so as to observe the event over the ocean as the Sun was only about eight degrees above the horizon. Unfortunately, the sky was totally covered by cloud and poor Rev Scott saw nothing.
A much later eclipse that is still remembered by older astronomers is the one that passed over Melbourne on 23 October 1976. The eclipse took place in the late afternoon and lasted two and a half minutes. Many astronomers from Sydney travelled to the town of Bombala in the south of NSW and near the Victorian border to view the event. On the day there were patchy clouds and most observers missed the event though others nearby had a good view.
A later eclipse occurred on 4 December 2002 with the track of the eclipse passing through parts of South Australia. Many groups of amateur and professional astronomers travelled to Ceduna for the event. I led a Sydney Observatory group together with space expert Kerrie Dougherty from the Powerhouse Museum. We did not go Ceduna, but took the opportunity to visit the Woomera rocket range as that also on the track of the eclipse. The eclipse took place in the late afternoon with the Sun already near the horizon and lasted just under 30 seconds. From Woomera the sky was completely clear and we had a wonderful view as illustrated in the photograph above. Those who travelled to Ceduna also saw the eclipse in between clouds that cleared only at the last second.
The next eclipse to be seen from Australia will take place on 14 November 2012 and will be best seen from Cairns in North Queensland. It will be in the early morning with the Sun very low on the horizon so the possibility of clouds has to be considered. Once again there will be the opportunity to join a Sydney Observatory tour group and details will soon be available on the Observatory website. In the meantime I have prepared a factsheet with full information on the event for the Astronomical Society of Australia.
For those from Sydney who do not want to travel and have the patience to wait there will be a total eclipse visible from Sydney on 22 July 2028. It should be an excellent eclipse occurring in the middle of the day with the Sun high in the sky and lasting for almost four minutes. Let us hope that the clouds will be kinder than they were for Rev Scott back in 1857!