It’s that time of year again! That is, it’s NASA Authorization Act time.

Mostly, I agree with Dr. Steve Squyres’ views. NASA does need a clear long-term goal, it is getting too little support for its missions, and it would be best to leave implementation details up to the space agency’s own program management. But that’s not what I want to discuss here.

What I want to write about is the troubling effect NASA budget and mission discussions has on space advocates. They get the Mars people at the throats of the human exploration people, as the space technologists snipe at Earth science supporters. Meanwhile, the pro-aeronautics camp trashes the education outreach groups and the outer moons proponents try to make off with the fundamental scientists’ stuff.

Everyone wants a piece of the pie, and there’s not enough to go around.

The resulting NASA policies over the past several decades years have been on the incoherent side, and I think that is because the space community shies away from a really difficult question – a question that we currently cannot answer well. The crucial thing that we have to pin down is this:

What is the driving purpose of our space program?

I don’t mean to ask whether we should or should not have a space program. Suppose the answer is “yes.” Now, we need to identify what it’s for. What do we want out of NASA?

The reason why I want to ask this question is because NASA’s short- and long-term goals should fall out as consequences of our answer. We need not bicker over whether we should build a Space Launch System or wrangle an asteroid into lunar orbit. The value of those items should be clear when we measure their contribution to the overall NASA mission.

I also don’t mean to ask whether NASA’s goal should be the Moon or Mars. Those are points on the map, and they are not ends in and of themselves. They are destinations, not purposes. Even if we get to the destinations, the space program will not thrive without a purpose. We’ve seen that before.

So let’s ask ourselves the big question. The one that space advocates don’t want to talk about, I think, because they are afraid of sounding a little crazy when they answer.

Is the answer, for example, that we want NASA’s purpose to be to find extraterrestrial life? Should the space program’s goal instead be to expand human life to colonies beyond our home planet? Or ought NASA’s biggest prerogative be defending the Earth from asteroid impacts? Do we have such a need for tangible short-term benefits that space technology development is the best answer? Should cranking out fundamental scientific research be the main goal of the space agency?

I contend that each of these answers implies that some destinations, missions, and technologies would be better choices than others. This is a good thing, because then our overall purpose for NASA will clear up the annual muddle. For example:

• If NASA’s purpose is to find alien life, then we ought to be sending as many robotic probes as we can to get under the ice of Outer Solar System moons like Europa, Enceladus, and Titan.
• If the goal is sustaining human colonies on other worlds, then human exploration of Mars and/or the Moon should get the lion’s share of NASA attention.
• If planetary defense is the motivating goal, then the space program should be doing all it can to characterize, explore, and learn to manipulate asteroids and comets.
• If space technology is the purpose, then NASA probably ought to be developing and expanding on the International Space Station.
• For basic scientific research, the agency should be putting up all manner of space telescopes and sending probes to easy-to-reach targets, like Mars.

I don’t mean to suggest that NASA should do nothing else. But the main thrust of NASA activity really should support the overall goal directly.

Personally, I think the main purpose of the space program should be to locate extraterrestrial life (with human colonization a close second). Discovery of alien life would be a world-changing event. I think that’s the kind of impact we should be trying to achieve. Locating extraterrestrial life wouldn’t be the end of the story, either – if it is found, then other goals will quickly ensue. So, I see that as a good self-perpetuating purpose for the space program. (Human colonization of space is a close second.)

I want a big, ambitious purpose for NASA. I want that purpose to be unambiguously clear. And I want the purpose to be persistent enough to drive budget authorizations for enough political generations that we actually see progress towards the goal. In order for all that to happen, though, the space community needs to first identify the goal!