Robotic Exploration Versus Manned Exploration

A decades long debate has existed over the merits of robotic exploration, using deep space probes and landing robotic rovers, instead of manned missions.

Supporters of manned missions have cited the large and ever increasing numbers of scientific papers based on data generated from the Apollo mission in the four

decades since Apollo Moon landings. The area covered by the astronauts, onsite human judgement for sampling or executing experiments, and the efficiencies and problem solving of manned exploration are often cited as advantages.

Robotic exploration is less expensive and more resource efficient. When the kind of resources necessary to accomplish a manned Mars mission, dozens of robotic missions can be planned and accomplished for robotic exploration of a good part of the Solar System, including the large major planets and visiting comets and asteroids. Without the burden and risks of keeping astronauts alive in space, robotic exploration does not need advanced propulsion to lessen the transit time, heavy and cumbersome shielding from radiation, or life support systems. As is done now, planetary gravity assisted deep space probes can take years to arrive at their solar system goals and accomplish their missions.

The drawback to robotic exploration are twofold. One is the risk of equipment failure that is difficult to correct in-flight. The Jupiter probe Galileo is a prime example. After its launch, the main antenna failed to fully deploy. Despite repeated attempts to dislodge and free 3 of the 18 antenna ribs, the main antenna never was fully functional. Fortunately, a secondary low-gain antenna was used in the main antennas place to transmit data, but at a reduced bandwidth. The lower bandwidth resulted in slower transmission speed, and only 70 % of the Galileo scientific goals being met.

The second drawback is that a robotic mission does not capture the imagina­tion of mankind. Great accomplishments and discoveries have result from robotic missions, but the lack of a human presence does not produce the public excite­ment. People don’t remember where they were when Surveyor 1 landed on the Moon, but people remember where they were and how they felt when Apollo 11 landed and Neil Armstrong took his first step on the lunar surface. Robotic mis­sions do not produce the same exhilaration of the human spirit as manned explo­ration does.

A possible alternative that is the hybrid of both types of exploration is a manned mission to Mars orbit, with the deployment of a robot astronaut remotely controlled from the manned Mars spacecraft in orbit. A human astronaut would have realtime control capability of a robot astronaut on the Martian surface for exploration and experimentation.

One of the current problems of controlling Mars rovers, such as Curiosity, Spirit, or Opportunity, is the 5-20 minutes command latency because of the distance from Earth to Mars. A manned spacecraft orbiting Mars can launch a robot astronaut for landing on the Martian surface and provide realtime or near-realtime control. Greater selectivity of samples and human-like dexterity can be designed into a robot astronaut. New robotic technology can provide a remote controlled human analog on the surface of Mars without the risks of exposing humans to the chal­lenges of landing on, surviving the Martian environment, exploring, and lifting off the surface of Mars. A large cost savings can result by removing the technological challenge of landing on and taking off the surface of Mars. Multiple robot astro­nauts could be deployed over different areas of Mars during the same mission, achieving greater coverage of the planet. Multiple deployment maximizes the mission effectiveness, and maximizes the cost efficiency of the mission. The robot astronaut can be switched off at mission’s end, and possibly used in future mis­sions – more bang for the buck. No life support concerns would be incurred on the Martian surface. The risk to human life, and overall mission risk would be lessened with this type of hybrid mission, while providing greater control of experiments and Martian sampling than currently available with Mars rovers. A simpler, more cost effective, more efficient, and less risky manned Mars mission may be achieved with this type of hybrid man-machine approach.