1945 and all that

This is part 9 in my series on the history and impact of distance education. Yesterday in Part 8 we saw how the television was conceived and invented. However, before the introduction of geosynchronous satellite technology, global telecommunication was problematic, and global distance education continued at the pace of the snail mail whilst radio and audioconferencing the mainstay distance communication media.

1945 is a momentous year in the history of the development of distance education technology. It was not only the year we saw the back of the Second World War. It was in this year that a young English scientist published a seemingly outlandish article in the magazine Wireless World.

The article, entitled Extra-Terrestrial Relays speculated that if three radio transmitters were placed at equidistant points at a precise altitude above the Earth's equator, they would be able to achieve global communication coverage. This is a facsimile of the original article. The author of the article was none other than the now celebrated science fiction writer Arthur C. Clarke (author of 2001: A Space Odyssey and other stories), and the article was instrumental in opening the debate about the feasibility of global communication satellites. Just 12 years later, on October 4th 1957, the USSR succeeded in launching the world's first artificial satellite, Sputnik, into orbit - and the Space Race began.

The most important aspect of Clarke's theory was the placement of the satellite at a precise orbit of 22,300 miles over the Equator. At this altitude, Clarke speculated, the satellite would have exactly the same velocity as the rotational speed of the Earth, and it would therefore appear to be stationary in the sky. This technique is now well established, enabling satellite users to dispense with expensive tracking devices. Communication satellites are placed into geosynchronous orbit, and this zone of optimum distance above the Equator is now referred to as the Clarke Belt. If you are in the Northern hemisphere, you will see that satellite dishes tend to point South toward the Equator. In the Southern hemisphere the opposite applies. In Equatorial regions, it's a common site to see satellite dishes pointing right up at the sky, and some have holes drilled in them to drain the rain water out! Queen Elizabeth II knighted Clarke for his services to science in 2000. Sir Arthur C. Clarke retired to the island of Sri Lanka where he died in 2008.

In 1965, Clarke's dream was realised when the first ever geosychronous communication satellite was positioned in orbit above the Atlantic Ocean by NASA. By 1969, three satellites had been linked to achieve the first fully global satellite coverage. For more on the uses of satellite technology in distance education visit here. Today, a lot of distance education provision is dependent upon geosynchronous communication satellites, and we take for granted the ability to talk to people on the other side of the world via telephone, video or other means. Watching live events from around the world on television is not something we think of as particularly special. We are so used to the idea that satellites are there, we give them no second thought. If they suddenly disappeared though, I think we would all know it.

On Monday: Part 10: University of the second chance

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