Johannes Kepler lived in this house in Prague from 1609-1612; photo by Nick Lomb

THE 8 (ONLY 8!) TRANSITS OF VENUS POSSIBLY SEEN BY HUMANS

It was only after Galileo Galilei invented the telescope in 1609 that viewing a transit of Venus became possible.

While calculating astronomical events for 1629-30, the brilliant mathematician and scientist, Johannes Kepler, discovered that both Mercury ad Venus were likely to cross in front of the Sun.

1631 Nobody is known to have seen this transit of Venus – which occurred at nighttime in Europe.

1639 Known to have been observed by two people in England – Jeremiah Horrocks and William Crabtree.

Engraving of Captain James Cook; Brian Greig collection

1761 More than 100 teams of astronomers made expeditions to various locations around the world to view the transit of Venus. Some of these teams met with tragedy, some failed despite overcoming great tribulations, and quite a few people died in the endeavour.

1769 This was the transit of Venus which included an expedition led by Captain James Cook and after which his expedition were the first Europeans known to have landed on the east coast of Australia.

1874 Many more teams of astronomers around the world attempted to view this transit of Venus – including Henry Chamberlain Russell, Government Astronomer at Sydney Observatory. The telescope in Sydney Observatory’s south dome is the historic 1874 large refracting telescope purchased primarily to view the 1874 transit of Venus.

Transit of Venus camp at Woodford, NSW, 1874

1882 Scientific interest had waned by the 1882 transit of Venus because scientists had developed other methods of gauging the Sun’s distance. However there still were endeavours to view it. Unfortunately weather prevented any viewing from New South Wales; teams from Melbourne Observatory viewing in Victoria had more success.

There was no transit of Venus in the 20th century.

2004 Millions of people around the world – including hundreds at Sydney Observatory – shared the thrill of safely viewing the transit of Venus through projections from a solar telescope.

2012 Millions of people around the world will, once again, view this rare astronomical phenomenon.

2117 None of us will be around to see this transit of Venus. (Better make sure you don’t miss the 2012 transit of Venus then.)