1700s / 18th century history on the 1st of July
1770 : LEXELL’s COMET passed closest to Earth than any other comet in recorded history, at a distance of only 0.015 astronomical units, 2.2 million kilometres (1.4 million miles). The comet was discovered by Charles Messier, a French astronomer.
1800s / 19th century history on the 1st of July
1819 : COMET TRALLES aka The Great Comet of 1819 was discovered by Johann Georg Tralles, in Berlin, Germany. The easily viewed brilliant comet was the first comet that was analyzed using polarimetry*by François Arago. *Polarimetry is the measurement and interpretation of the polarization of transverse waves, mostly electromagnetic waves in the form of radio or light waves.Continue reading 1st JULY ~ HiSTORY ON THiS DAY