great comet 1861

One-hundred and fifty-three years ago today, on May 13, 1861, a young man in Australia looked into the starry sky above the outback and made a startling and beautiful discovery: a comet, not known or catalogued before, was becoming visible in the southern heavens. The young man was 27-year-old John Tebbutt, the son of a prosperous shopkeeper in New South Wales, Australia, and he made the discovery with an ordinary 3 1/4″ marine telescope.

The comet, which grew steadily in brightness over the next few weeks, was a pretty big deal. During the late spring and early summer of 1861 the Earth passed right through its tail, resulting in beautiful meteor showers. Tebbutt, who had begun astronomical observations at the age of 19, was already an accomplished star-watcher. He not only observed and recorded the positions of the comet, but he also calculated its likely orbit around the solar system. Based on his readings, modern astronomers believe the comet orbits our system about once every 400 years. It was probably last seen from Earth in the 15th century.

Because Australia was so remote at the time, news of Tebbutt’s discovery did not reach the rest of the world before people began to see it for themselves. On June 29 the comet was visible for the first time in the northern hemisphere. In early July it was particularly brilliant over the skies of the United States. By the late part of the month it was waning; it would probably not have been visible, for instance, in the night skies above the camps of Union and Confederate soldiers who were about to fight the Battle of Bull Run. But it could still be seen in telescopes until March 1862.

Tebbutt went on to be the first great astronomer from Australia. He built an observatory with his own hands in 1864, and began publishing his scientific works in 1868. He died in 1916, famous and decorated by scientific societies both in Australia and the greater British Commonwealth. Humans will not see the Great Comet he discovered until sometime in the 23rd century, but it seems likely that Tebbutt will still be remembered then. Perhaps it will eventually be called Tebbutt’s Comet.