The recent death of Dr. James Van Allen, opponent of human space flight, reminds us that the robots vrs astronaut debate is as old as the space age. The arguments go like thus:
Those who maintain that robots are sufficient to explore the high frontier of space point out that they are cheaper to send to various destinations in the Solar System than are human astronauts. Humans need food, water, air, and protection from radiation and temperature extremes in space that robots do not require. Robotic space missions, dating from the first Mariner probes to Venus and Mars in the 1960s, have returned volumes of data.
Those who argue for human astronauts counter that robots can only perform tasks that they are programmed to do. Even controlling robotic probes over a distance can be time consuming and difficult when radio commands take many minutes or hours to reach a space probe on the surface or in orbit around another planet. While human space exploration advocates concede that robots have their uses, they maintain that only human explorers, with their powers of observation and instinct, and the ability to react instantly to new phenomenon can fully appreciate conditions on an alien world.
Opponents of human space flight tended to be eminent scientists, such as Van Allen, made famous by the discovery of the Van Allen Radiation Belts, Dr. Thomas Gold, who proposed a controversial theory of the original of the universe called Steady State, and most recently Dr. Robert Park, a professor of physics at the University of Maryland and media gadfly. These and others have, from time to time, lent their names and an aura of academic authority to political opponents of human space flight in the United States Congress.
Opposition to human space exploration is not universal in the scientific community. The late Carl Sagan, a popularizer of science and originally a human space flight skeptic, concluded in one of his last books, The Pale Blue Dot, that human space colonies were necessary to preserve the human species. Dr. Paul Spudis, a planetary geologist at Johns Hopkins, who was involved with the Clementine lunar probe, has been a vigorous proponent of human space exploration.
Since the beginning of President George W. Bush’s Vision for Space Exploration, to send astronauts to the Moon, Mars and beyond, the robots vrs humans debate has heated up. Within a few weeks of President Bush’s announcement in 2004, Robert Park debated Dr. Robert Zubrin, an aerospace engineer and advocate for Mars exploration and settlement, on the subject at a symposium held by the Ethics and Policy Center in Washington DC. The debate was spirited and well attended.
More recently, in October of 2005, the Royal Astronomical Society conducted a study on the question of robots vrs humans in space. A commission comprised of scientists who had started as skeptical of human space flight, concluded that humans were needed to explore space after all.
Dr. Frank Close, Chair of the commission, concluded, “However, while fully recognising the technical challenge and the need for substantial investment, we have, nevertheless, been persuaded by the evidence presented to us that the direct involvement of humans in situ is essential if we are to pursue science of profound interest to humankind that can only be undertaken on the Moon and Mars. Autonomous robots alone will be unable to realise those scientific goals in the foreseeable future.”
Case close? Probably not. The robots vrs humans debate has always been more political than scientific and therefore, for some, will be impervious to scientific arguments. As recently as two years ago, Van Allen published an essay in Issues in Science and Technology in which he suggested that human space flight was “obsolete.”
Opponents like Van Allen and Park have not commented, so far as anyone knows, on private efforts to launch people into space, inspired by Burt Rutans flight of SpaceShipOne. If, as many expect, commercial space flight gets off the ground, then another argument for human space flight will trump all of those that have been made against it. One can make money doing it.
Even aside from commercial possibilities, it seems that human space exploration advocates have the better argument. Those who suggest that robots alone can explore space have a tendency to oversell the capabilities of robots. Even with modern artificial intelligence software, human beings remain superior as explorers of unknown places such as alien worlds. As Dr. Zubrin pointed out in his debate with Robert Park, “The human explorer can follow up on all sorts of intuitive clues and observations. Out of the thousands of rocks he has glanced at and the hundreds he has looked at more closely-perhaps he brings ten samples back into the habitat. There he can look at them with a hand-lens; he can thin-section them; he can examine them under a microscope.”
Human beings conduct exploration on Earth all the time, often in hazardous environments such as the bottom of the ocean, the close vicinity of active volcanoes, and Antarctica in the depths of winter. Zubrin again: “On Earth, fossil-hunting involves hiking long distances through unimproved terrain, and climbing up steep hillsides or cliffs. It involves digging and pickax work, as well as delicate handiwork, like carefully splitting open shales edgewise to reveal the fossils that have been trapped between the pages of rocks pasted together. This is far beyond the ability of robotic rovers like Spirit and Opportunity. If you took one of these robots to a paleontological dig on Earth, the researchers might use it as a platform for putting coffee cups on.”
Of course, space exploration is not all about gathering data or taking pretty pictures. It is first about appreciating the grandeur which is the universe. One thing that a robot can never do, no matter how sophisticated its software, is experience awe.
And if we conclude, as Carl Sagan and many others have, that the spread of human beings out across the solar system is crucial to the survival of the human species, then human space exploration is mandatory. While robots are very good tools, they make very poor space settlers. Years and decades hence, when humans are a multi planet species, it will be because of the efforts of both humans and robot explorers.