Succession of satellites keep eye on Earth
Excerpt from the January 22, 1966 issue of Science News Letter

VIEW FROM ABOVE A plume of gas and ash spill from Mount Etna in this image captured December 3 by the Landsat 8 satellite. A fleet of Earth-monitoring satellites was proposed in 1966; Landsat 8, launched in 2013, is the youngest.
USGS/NASA Landsat