MOONWATCH: The First Satellite Tracking Network

The International Geophysical Year ran 18 months from July 1957 through all of 1958, and the part of the IGY that involved the Pacific Rocket Society was the MOONWATCH program run by the Smithsonian Astrophysical Observatory. This was a world-wide network of volunteers who set up stations to track the first satellites. Each station had fourteen small telescopes sighted along the meridian at different elevations from the north and south horizons and an observer looking into each one. If and when the observer saw a bright point of light that was obviously not an airplane he would mark the time it entered the field of view, crossed the center reticle and exited as well as estimating the approximate bearing. All of this information was electronically recorded and forwarded to SAO headquarters where it was compiled with reports from other stations to establish the satellite’s orbit.

Bob Citron took the lead in organizing the MOONWATCH station and served as its director. Through PRS members who worked for the Rocketdyne and Atomics International units of North American Aviation we asked for money to buy the telescopes and set up the station on campus. The company stalled until – October 4, 1957. A check soon arrived and the station became a reality.

Viewing conditions in that part of LA weren’t the best – this was the smoggy fifties – and we shortly moved the station to a cliff-side location in Woodland Hills on the San Fernando Valley side of the Santa Monica mountains. This meant a long drive (I lived in Redondo Beach) to get to the station when a sighting was predicted, but the sky was much clearer. Also, you could hear the test firings at Rocketdyne in the Santa Susana mountains. Hard to believe but twenty people would show up before dawn for a chance to sit at a telescope and maybe see a satellite or to help out in other ways.

John Porter (left) and Bob Citron are pointing at the star chart and I’m seated between them. The MOONWATCH telescopes and observers are on the right.

Bob Citron made satellite tracking a career with the Smithsonian Astrophysical Observatory after graduating from Northrop and later became a leader in the private rocket field