July 1 – Lexell's Comet passes closer to the Earth than any other comet in recorded history, approaching to a distance of 0.015 AU. It is observed by Charles Messier between June 14 and October 3.[1]
April 18 (April 19 by Cook's log)[2] – Captain Cook and his crew become the first recorded Europeans to encounter the eastern coastline of the Australian continent.
April 28 (April 29 by Cook's log) – Captain Cook drops anchor in a wide bay about 16km (10mi) south of the present city of Sydney, Australia. Because the young botanist on board the ship, Joseph Banks, discovers 30,000 specimens of plant life in the area, 1,600 of them unknown to European science, Cook names the place Botany Bay on May 7.