Crockett Grabbe
August 1, 1999
We just celebrated the 30th anniversary of the landing of United States astronauts on the moon. Vice-President Al Gore awarded the prestigious Langley Gold Medal for Aviation to the 3 original lunar astronauts, and several former astronauts were interviewed on shows because of the anniversary. What insights were gathered for the future of the space program?
One of the issues repeatedly brought up in shows and interviews was the sentiment that it has been 30 years since we landed humans on the moon, and it is about time now to land humans on Mars. Should that goal be an important one in our space program? After all, on the 20th anniversary of the lunar landing in 1989, President George Bush set forth, in a space policy address to the National Aeronautics and Space Administration, the goals of deploying the space station, developing a base on the moon, then developing a base on Mars. In fact, putting humans on Mars is often referred to as a goal by NASA spokespersons. However, pursuit of such a goal would prevent many other worthwhile projects in the space program, and could burgeon the space budget to an intolerably high level.
The initial project to "land a man on the moon" within a decade was set forth by President John Kennedy in May, 1961. That goal gave focus and priority to the space program, which served as a race of pride with the Soviets -- a peaceful one, compared with the potentially destructive one with the nuclear arms race. It was a timely program and one we needed to develop our technology and national capabilities in space. The goal was accomplished with 3 astronauts losing their lives in the process. However, the situation is quite different now than it was in the '60s. The need for manned spaceflight exploration should be evaluated against the current conditions, rather viewing it as a necessary extension of of the moon program. The country has already committed to the manned mission of creating a space station in orbit around the Earth. But what about missions of creating human colonies on the moon and on Mars?
The conditions on the moon are very hostile to colonizing. Although it would be feasible, the cost of doing so would be quite prohibitive. The potential of mining on the moon has been held out as the attractive return for a colony on the moon. But for the foreseeable future, the potential return from mining operations would not begin to pay for the costs of maintaining a colony on the moon. For a start the day-night extremes of temperature, the probable lack of adequate water, and the complete lack of atmospheric pressure will each require expensive solutions. To approach economically feasibility, the mining operation will instead need to be set up so that most of the work is done by unmanned systems and controlled from Earth. Humans then could make occasional trips there for maintenance and transport as needed for the operation.
Part of the motivation for landing humans on Mars has been the long-existing science-fiction scenario of creating colonies on other planets. Mars has long been viewed as a feasible place colonies could be established. The temperature extremes are more mild than on the moon, and there is probably adequate water sources in the underground permafrost. On the other hand, the atmospheric pressure is only about 1% that of the Earth's atmosphere, and has a very low oxygen concentration. So is establishing a colony on Mars more attractive than establishing one on the moon?
The problem with sending men and women into space is that the cost is over 10 times that of sending unmanned spacecraft to accomplish a similar mission. Space is a very hostile environment for humans, and the necessary life-support systems considerably increase the cost of the mission. While one may argue that unmanned missions, such as the Mars Observer in 1993, failed because they were unmanned (a questionable argument), the cost of that failure is miniscule comparted to the 2 billion lost with the Challenger disaster. This is not to be mention the REAL loss on challenger: the lives of 7 astronauts.
The cost of transporting astronauts over more than 100 million miles of space, along with the tremendous cargo that will be needed to try to establish a liveable environment there, would be astronomical compared to the costs of unmanned missions to Mars. Only in the last 2 years have unmanned missions returned to Mars for serious research after the 20-year hiatus following the Viking missions. That long hiatus occurred because the priority in the meantime was set elsewhere in the limited resources that make up the NASA budget. We do not need to strain and usurp those resources with the astronomical cost of putting astronauts on Mars.
The cost of establishing a base on Mars would undoubtedly run into the hundreds of billions of dollars. Meanwhile, several unmanned missions are delayed or canceled because of constraints on the budget and the spending priority that is placed on manned missions involving the space shuttle and the space station. The Galileo mission to Jupiter is an example of a mission that was delayed almost a decade because of shuttle priorities; the 3-year delay after it was finally ready to go led to the failure of its high-gain antenna, its primary communication link with Earth. In spite of this problem, Galileo has provided us with incredible data on Jupiter and its moons.
I proposed just after the 20th anniversary of the lunar landing that 50% of the civilian space expenditures should go into unmanned research and exploration.* The proposal is just as true today as it was 10 years ago. If this policy was followed, the number of inexpnsive unmanned space missions would blossom, providing greater overall benefits of the space program to the citizens of this country.
* Des Moines Register, August 12, 1989