July 22nd in Astronomy and Space Science
![]() | 1784 | Prussian astronomer Fredrich Bessel born. He is the first to use the concept of parallax to measure the distance to nearby stars. By charting a star's position at two times, six months apart, he uses the diameter of the Earth's orbit, about 310 million km (186 million miles), as his baseline. His first measurement, on the star 61 Cygni yields a distance of 11 light years, very close to today's accepted value of 11.1. |
![]() | 1962 | US launches the Mariner 1 probe, a Venus fly-by. It veers off course shortly after launch and is destroyed by the range safety officer. |
![]() | 1972 | Soviet Venera 8 spacecraft lands on Venus. It conducts a soil analysis and transmits data for 50 minutes before failing under Venus' extreme pressure and temperature. |