Topic of the Moment – From fiction to fact

The DNA of the late science-fiction writer Arthur C Clarke is set to be placed aboard a spacecraft named after one of his short stories, based on a race between craft driven by solar sails.

The DNA of the late science-fiction writer Arthur C Clarke is set to be placed aboard a spacecraft named after one of his short stories, based on a race between craft driven by solar sails.

Many of the futuristic technologies about which Clarke wrote have become reality – or are in the process of doing so. These are some of the most notable:

Communications satellites

Clarke is credited with coming up with the concept of the communications satellite.

A letter from Clarke to the editor of Wireless World in 1945 described his idea of using satellites in geostationary orbit – they remain above a particular location on the Earth’s surface – as communications relays.

A constellation of such satellites can transmit messages between themselves and then on to any point on the globe. The world’s first communications satellite, Telstar, was launched in 1962, and they’re now used for television and internet broadcasts as well as their original purposes of voice communications and navigation.

The geostationary orbit is now sometimes known as the Clarke Orbit.

Artificial intelligence

In Clarke’s best-known work, 2001: A Space Odyssey, the spacecraft taking astronauts David Bowman and Frank Poole to the outer planets is looked after while its crew is in suspended animation by the computer HAL.

While true thinking machines are still not possible, simpler forms of artificial intelligence are commonplace, and computers can beat even expert players at chess and some forms of poker.

One voice-operated personal assistant for the PC is even named for HAL, and such software has been popularised by the most advanced programme of its type, the iPhone app Siri. Unlike HAL, however, Siri probably won’t try to kill its users.

Space elevator

Although first outlined by Konstantin Tsiolkovsky, the idea of an elevator reaching all the way into space was popularised by Clarke in his novels The Fountain of Paradise and 3001: The Final Odyssey.

Tsiolkovsky’s elevator was to be a compressive structure built upwards from the Earth into space, but no known material can support its own weight at such a large height. Instead, subsequent investigations into the possibility of a space elevator called for building a tensile structure from geostationary orbit downwards.

When carbon nanotubes were developed in the 1990s it was quickly realised that they would have the necessary tensile strength for a space-elevator-like construction. A feasibility study carried out by NASA and published in 1999 suggested that a space elevator would be possible in the next 50–100 years, and would be able to put people and cargo in orbit for a few dollars per kilogram, compared to around $20,000 when transported by space shuttle.

2001 also predicted that its titular year would see the first stages of colonisation of the Moon and that commercial space travel would be widespread, which is obviously not the case. But with the first resupply of the International Space Station by a commercial company earlier this year, perhaps it isn’t too far off.



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