Open thread for night owls: Telstar 1 ushered in the 'via satellite' age 50 years ago today

Telstar 1 (NASA) At Wired, Adam Mann reminds us of a breakthrough that was put into orbit a half-century ago. It was the privately owned Telsar 1. Ma Bell, as we called the telephone monopoly back then, owned it. The signals it sent from its asynchronous orbit could include 600 simultaneous phone calls, and a single black-and-white TV stream:

Telstar 1 was built as an international collaboration between AT&T, Bell Labs, NASA, the British General Post Office, and the French National Post, Telegraph, and Telecom Office. The satellite launched on a Delta rocket on July 10, 1962.

The aluminum satellite was wimpy by modern standards. It used 14 watts of power ' roughly one-seventh that of a modern laptop ' generated by the 3,600 solar panels on its outer hull. As well, it could only carry 600 phone calls and one black-and-white TV channel, though not much more was really needed at the time. [...]

Before Telstar was launched, microwave towers could flash TV shows and other communication information from point to point through the air, supplementing the landlines that already crisscrossed the globe. But once these signals reached the ocean, they reached their limit.

Satellite transmission allowed instantaneous communication ' such as long-distance phone calls and real-time international TV ' to become an everyday reality. The phrase 'live, via satellite' is only possible with Telstar and the machines that followed it into space.

Telstar 1 relayed its first image, a flag outside Andover Earth Station, to Pleumeur-Bodou on July 11.

Bill Ray writes:

Arthur C Clarke is often credited with inventing the idea of satellite communications, though in fact his contribution was to point out that three birds in geostationary orbit could provide global coverage. Geostationary orbit is more than 35,000km up, beyond the reach of radios in 1962, so Telstar's orbit peaked at less than 6,000km up and dipped down to less than 1,000km during its two-and-a-half-hour circumnavigation.

That dip is also what caused Telstar's downfall. Its repeated drops into the Van Allen radiation belt did allow the satellite to gather information about the belt (which was part of the plan) but the information it gathered was largely the havoc such radiation plays with electronic circuits. If Wikipedia is to be believed then US nuclear tests at the time had left the Van Allen particularly charged, but either way the satellite failed intermittently for a few months and finally stopped relaying signals entirely in February 1963. However, it remains in orbit to this day, faithfully tracked by the US government as required by international treaties.

Telstar was solar powered, with 3,600 solar cells feeding 19 nickel-cadmium batteries which received a 6GHz signal and retransmitted it with 2.25w of power at 4GHz. The electrics necessary were all suspended by shock-absorbent nylon cords in the middle of the spherical body, which had to spin at 180 rpm for stabilisation (gyroscopes perform the same function on modern satellites, but weren't reliable enough back then).

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