By James Donahue

As an old science fiction fan and a guy who has followed the U.S. and world space programs with great interest ever since the Russians sent Sputnik in orbit, it seems incredible that I would be saying this. But I believe the nation should give up on any plans to send humans to Mars.

Back in 1950 when Ray Bradbury published his popular science fiction work The Martian Chronicles, there was a belief that perhaps there was once life on Mars, and that it would be possible for us to establish colonies there again.

When Richard Hoagland published his famous image of a mile-wide rock that looked like a carved human face, shot from the Viking Orbiter in 1976, and showed other nearby images that looked somewhat like the ruins of a city, complete with a pyramid, there was much speculation that Mars was, indeed, a place for humans to move if the going got tough on Earth.

New images, however, and extensive data gathered by a number of NASA missions to the red planet since then have shown that Hoagland's images were not depicting what was really there.

We have also learned that while the pre-biotic chemistry from which life might have sprung was present, atmospheric conditions, temperatures and other extremes never allowed it to materialize. For all practical purposes, at least in our three-dimensional existence, Mars is a dead planet.

Consequently we believe it would be a great expense that Americans can no longer afford, and a clear risk to human life, to attempt a human mission to Mars and back.

If America was the nation it used to be when John F. Kennedy was president, and we could engineer and build a mission to the Moon at the price it cost us, such an adventure might have been worth the effort, if only to quench our adventuresome spirit. And It still would be if we were living in a healthy world and the world economy was booming as it should be doing.

The robotic machines we have sent to Mars to date have recorded and transmitted volumes of vital information about that planet, but not yet enough to help plan for a manned mission. The next planned mission, the landing of a full science laboratory, which was set for 2010 has now been stalled until 2011 due to financial restraints. If the economy tanks any further it may be stalled indefinitely.

The possibility of sending a manned flight to Mars cannot be considered until the robotic machines complete a detailed study of the planet, found vital sources of water, returned soil samples to Earth to show that food can be grown in greenhouses, and other vital information. When humans go, they will have to establish a base from which to maintain life support using resources found on the planet.

The cost of a mission like that may be so high it would require the resources of many world nations. Based on current technology, the 47-million-mile trip would take from four to six months. And because the beginning of the return trip would depend on the proper alignment of Earth and Mars, the astronauts who arrive on Mars would have an 18-month wait before they could blast off again for a return trip. Thus the entire mission would keep these travelers in space or on the surface of Mars for at least three years.

That would mean a lot of oxygen, water, food, and other basic necessities would have to either go with the Mars team, or be found on Mars to maintain life support while they wait for the trip home.

The concept of landing on Mars at a site near water, then erecting permanent structures in which to live and remain protected against the harsh sand storms, violent winds, extreme temperatures and other dangers, finding water, growing food and generating enough breathable air to sustain life for an 18-month visit seems almost mind boggling.

And in the end, would it be worth the effort? We might learn if Mars could sustain self-sufficient colonies in the event of a global extinction threat on Earth, or if the planet offers new commercial opportunities. When you think about it, we may already have the answers to these questions. And if not, the robots we send there can get the answers.