1978 – The International Ultraviolet Explorer satellite (IUE) launched into geosynchronous orbit. A joint project of NASA, ESA and PPARC, it’s years of operations returned 104470 high- and low-resolution images of 9600 astronomical
sources from all classes of celestial objects in the 1150-3350 Å UV band. The space telescope was turned off September 30, 1996.

1962 – Ranger program: Ranger 3 is launched to study the moon. The space probe later misses the moon by 22,000 miles (35,400 km).

1949 – The Hale telescope at Palomar Observatory sees first light under the direction of Edwin Hubble, becoming the largest aperture optical telescope (until BTA-6 is built in 1976).