Since the first Apollo landing in 1969, NASA has been looking, unsuccessfully, for an overarching goal to match this spectacular achievement: landing men on the Moon.  The International Space Station (ISS) has not turned out to be what it was advertised.  It has made no breakthrough scientific contributions; it has not explored the solar system further; and it has not excited a great amount of public interest since it was set up.  In retrospect, many would refer to it as a white elephant.  Its annual maintenance costs are a drain on the NASA budget.  Even worse, its supply has to be contracted out -- to Russia.  The trouble is: ISS had no well-defined goal.

Yes, there have been plenty of proposals.  During the first Bush administration, NASA thought it had a clear go-ahead and proposed a manned Mars mission, in addition to putting a manned base on the Moon (to do what?).  But once the price tag was revealed, around 400 billion dollars (which was then real money), the NASA plan was DOA (dead on arrival).

Since then there have been proposals to establish a permanent colony on the Moon -- again without any clear justification.  Many have compared it to the ISS and labeled it another white elephant.  In fact, it would add little to our knowledge of the Moon, and probably would not even create much public excitement: "Been there, done that" -- to much of the public, just a repeat of the Apollo mission.

Such a Moon colony has been labeled as an important 'step towards the human exploration of Mars'; but this claim was never justified in any detail.  Many would describe it as a detour, or as a blind alley.  Even worse, it would consume so much of the NASA budget as to make any other space project infeasible.

More recently, we've heard proposals such as landing on the far side of the Moon, to set up radio telescopes in a noise-free environment.  There might be some justification for this, but it is an expensive undertaking without commensurate returns. 

Similarly, we've heard of human missions to asteroids, as worthwhile goals.  But there are likely to be as many kinds of asteroids as there are meteorites.  And these can be studied more easily in samples taken from the dusty shelves of museums around the world.

It is interesting to contemplate the military aspects of space but hard to think of any beyond Earth orbit.  Yet I well remember that during the early days of the space race with Russia, there were Pentagon proposals to "occupy" the Moon.  Why? Because it is military doctrine to occupy the high ground.  And why high ground?  Well, whenever we see the Moon, it's "up there," the generals replied.  I spent much time explaining that the Moon is not an ideal place from which to launch nuclear missiles.

Among the more imaginative proposals has been the occupation of libration points, places where opposing gravitational forces of celestial bodies balance to zero.  These have been suggested as places for storing anything -- from propellants to pieces of asteroids. There may even be international competition for libration points.  But since there are several, it should be a simple matter to divide them up between the major space-faring nations.  Another great project for the United Nations and for the State Department!

The latest proposal is to capture a small asteroid and bring it to a libration point, where it would remain more or less stationary -- so it can be studied at leisure.  Again, it is being sold as a step towards Mars -- probably an idea thought up by some armchair astronaut in the White House.  The project really does not make any sense.  The selected asteroid would be some 5-10 meters in size, a little larger than the Ahnighito (Cape York) meteorite in the New York Museum of Natural History.  But there are plenty of meteorites that can be studied at leisure by scientists; no need to go out and get another one.  They come here all the time -- unannounced and sometimes very destructively.  We should really be more concerned with deflecting incoming asteroids before they hit the Earth and cause widespread damage.

Writing in Science magazine (10 May 2013), well-respected planetary writer Richard Kerr reports that the community of asteroid scientists is not enchanted by such a project.  But they seem to be willing to go along if that's all that's out there for NASA. 

There may be a way to finesse the issue, however.  Mars has two small moons, Phobos and Deimos.  Some believe that they are asteroids, captured by Mars billions of years ago.  [I plead guilty for having advanced such a possibility in 1968 but I certainly no longer believe it.]  So let's just label the Martian moons as asteroids; it's for a good cause.

[Full disclosure: I should also mention that about 40 years ago I proposed capturing Phobos, in order to exploit its possible mineral resources.  Not a brilliant idea, but TIME magazine liked it.  In my defense: I needed a topic for a popular talk; also, I wanted to prove a Russian astrophysicist wrong; he had advanced the idea that Phobos was hollow and had been constructed by Martians!]

All these attempted justifications for projects as "stepping stones" to Mars lead us to the obvious question: why not go directly to Mars?  If done properly, the initial steps are well within present capabilities and current budgets.  The scientific returns from studying another planet like Mars would be immense: its climate history and current meteorology; its composition, both surface and interior; the fate of past atmospheres, oceans and its planetary magnetism.  A major question for decades has been the origin of the Martian moons: how did they become associated with the planet -- and have there been other moons that have by now disappeared?

But the holy grail of Martian exploration has always been the development of life in the past, the discovery of paleo-life.  The key question will be to learn whether life developed in ways similar to Earth or whether our planet is unique.  No such life is likely to exist on the Moon, nor on asteroids, and certainly not at libration points. 

Mars presents our only realistic opportunity to discover facts that not only advance science but also impact on philosophy and even theology.

S. Fred Singer is professor emeritus at the University of Virginia and director of the Science & Environmental Policy Project.  His specialty is atmospheric and space physics.   An expert in remote sensing and satellites, he served as the founding director of the US Weather Satellite Service.  An active member of the Meteoritical Society, he pioneered the widely used  cosmic-ray method of dating meteorites.  For recent writings see http://www.americanthinker.com/s_fred_singer/ and also Google Scholar.