On May 13, 1861, Australian astronomer John Tebbutt discovered C/1861 J1, the Great Comet of 1861. C/1861 J1 is a long-period comet that was visible to the naked eye for approximately 3 months. It was categorized as a Great Comet, one of the eight greatest comets of the 19th century.
John Tebbutt was first educated at the Church of England parish school and later at a private school. After his retirement, his father purchased some land east of Windsor. This later also became the site of John Tebbutt’s observatory. He began his observations at the age of 19, probably using a regular marine telescope and sextant.
On May 13, 1861, Tebutt discovered the 1861 comet. The young astronomer was acknowledged as the first discoverer of C/1861 J1 and the first computer of its approximate orbit. The long-period comet was visible to the naked eye for approximately 3 months. It was categorized as a Great Comet, one of the eight greatest comets of the 19th century, according to Donald Yeomans. The comet made its closest approach to the Earth at a distance of 0.1326 AU. At that time, it was estimated to be between magnitude 0 and −2 with a tail of over 90 degrees. C/1861 J1 could even cast shadows at night, and the famous comet observer J. F. Julius Schmidt watched in awe as the great comet C/1861 J1 cast shadows on the walls of the Athens Observatory.
In 1864 he built a small observatory close to his father’s residence on his own. Tebbutt installed his instruments consisting of his 3¼-inch telescope, a two-inch transit instrument, and an eight-day half-seconds box-chronometer. Four years later, he published his meteorological observations titled ‘Meteorological Observations made at the Private Observatory of John Tebbutt,Jnr.‘
For the next 30 years, John Tebbutt continued publishing his records and published a series of papers in the Monthly Notices of the Royal Astronomical Society of London, in the Astronomical Register, London, and in the Journal and Proceedings of the Royal Society of New South Wales.
In 1881, Tebbutt discovered C/1881 K1, another great comet. He published his work in 1887 History and Description of Mr Tebbutt’s Observatory, and followed this with a yearly Report for about 15 years. John Tebbutt was elected first president of a branch of the British Astronomical Association which was established at Sydney.
At yovisto you can learn more about Comets and Meteors in a lecture by Robert Nemiroff.
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