New technologies, rarely foreseen by ‘futurists,’ often change everything. Just as science fiction could not predict the PC, so visionaries like Arthur C. Clarke could not predict the developments in electronics that would make his idea of geostationary relay satellites practicable. Yes, Clarke dreamed up the idea of such satellites, but he was talking about manned space stations handling the abundant telecommunications traffic that was to come. In a mere 15 years, it would become possible for radio technology to bring Clarke’s ideas to fruition, just as Earth observation, astronomy and military reconaissance would be performed by unmanned satellites.

Now we speculate about proposed manned expeditions to Mars, but is the future human or robotic as we push into the outer Solar System? Bob Parkinson tackles the subject in an essay in the March/April issue of the Journal of the British Interplanetary Society. Consider the march of machinery in the years since the first manned spacecraft. People are still in low Earth orbit (other than the still unduplicated Moon landings), but every planet except Pluto has been studied by robotic probes, and the New Horizons mission will leave for Pluto as early as this January.

Cassini has been triumphant in its still unfolding tour of Saturn space, we’ve touched down robotically on Venus, Mars and Titan, not to mention NEAR’s asteroid landing, and we’ve banged an impactor into an onrushing comet. It’s important to realize, Parkinson writes, that these are not just scouting missions for future human flights, but contributions to our knowledge in their own right, and perhaps a model for what is to come.

I can think of a variety of reasons why manned Mars missions will be tricky (and Parkinson lists them all, from dealing with zero-g over long flight times to radiation exposure hazards and problems of long-term, closed-cycle life support). Even so, he’s not arguing that men will never set foot on Mars as much as noting the reasons why robotics can help and sometimes take precedence over humans. Consider the possibility of life on Mars — if we find it via robotic rover, can we land people on the planet without contaminating it? Are our rapidly improving rovers capable of answering such questions without putting human crews on the surface?

And consider this intriguing virtual reality notion:

In 1997 the author suggested that if Mars was mapped down to very high resolution, it might be possible to create a ‘virtual Mars’ through which tourists could wander as they chose. Rather than using this data for science alone, direct access would allow ordinary people to actually see for the first time sights that had never been seen before by human eyes.

25 years ago, the issue of man vs. machine in outer space would not have had the resonance it has today. Parkinson concludes with a thought on funding and commitment:

Robotic exploration missions continue to be justified on the basis of their scientific value, and as a consequence compete for funding with other science programmes — not always successfully. The implication is that we must learn to find arguments which parallel those used by advocates of human spaceflight, which emphasize the adventure, heroism and (vicarious) participation aspects of exploration. Then the exploration (and exploitation) of the Solar System can become a joint carbon-silicon enterprise.

The paper is Parkinson, “The carbon or silicon colonization of the universe?” JBIS 58 (March/April 2005), pp. 111-116. Centauri Dreams hereby reiterates its lament that JBIS is unavailable in full-text form even on the major scientific databases, making a nearby research library all but essential unless you’re a subscriber.