On this day in 1964, Syncom 3 was put into orbit around the world. It was the first geostationary communications satellite. That means it was a satellite that stays in the place relative to the surface of the Earth. Or to put it a bit more technically, it orbits the Earth at the same speed that the Earth rotates. It’s really great for communication because it is always in the same place and can service the same part of the Earth.

In 1961, NASA started the Syncom — “synchronous communication satellite” — program. Syncom 1 was launched in 1963 to be in geosynchronous orbit. This kind of orbit moves around but ends up at the same exact location one day later. NASA got it in orbit, but not in geosynchronous orbit. So they moved on to Syncom 2. It achieved geosynchronous orbit on 26 July 1963. But it wasn’t until Syncom 3 that geostationary orbit was achieved.

Interestingly, even though none of these satellites have been used for over 45 years, they are still circling the earth. In the case of Syncom 3, it is orbiting at almost 7,000 mph.