We seem to be in one of those periods in which basic reasons for doing what we do as a nation are called into question. This includes our national civil space program, which for the last few years has engaged in an extended period of back-biting and navel-gazing. Much of this “debate” has focused on either or both of two points: what rocket to build and where to go, and not on sustainability.
In an era of limited resources, our challenge is to create a worthwhile space program with an expenditure rate that falls at or below a level perceived as affordable. Given this reality (regardless of prevailing agency direction or assertions about projected deep space destinations) it is highly likely that cislunar space will be the sphere of space operations for the coming decade or two. Thus the questions should be: What are we doing in space and why are we doing it? If the answer is a series of space exploration “firsts” (flags-and-footprints forever), that model will require specific activities and missions. If the answer is that an incrementally developed transportation infrastructure is desired, one that creates an expanding sphere of human operations, then such a model requires a different set of specific activities and missions.
Thus, the real debate is not about launch vehicles or spacecraft or even destinations; it is about the long-term – the paradigm or template of space operations. One model requires mega-rockets to distant targets for touch-and-go missions; for convenience, I’ll call it the “Apollo” template (no denigration intended). The other model is an incremental, go-somewhere-to-stay-and-then-expand-onwards mindset – call it the “Shuttle” template (again, same disclaimer). The one that you adopt and follow depends on what purpose you believe human spaceflight serves.
Because Mars may harbor former or existing life, NASA has presumed that it is our “ultimate destination” in space. In effect, the entire focus of the human spaceflight effort has devolved into a huge science project – “The Quest for Life” (which means finding pond scum, not ET). Thus, debate about what to build, where to go and how to do it must be formulated towards attainment of Mars.
This unspoken assumption has been at the root of most space objective studies for the past 20 years. Mars was the end point of President George H.W. Bush’s Space Exploration Initiative, President George W. Bush’s Vision for Space Exploration, of former Lockheed-Martin President Norm Augustine’s two reports, and a myriad of space groups and societies. From the 1990′s to the present, a multi-billion dollar robotic campaign has sent mission after mission to Mars, each discovering that the red planet once had liquid water. This mania for Mars and preoccupation with possible life there, has blinkered our perceptions of the space program and distorted our reality of what is possible or attainable on reasonable time scales with available resources.
Long term, the goal for human spaceflight is to create the capability to go anywhere we choose, for as long as we need, and do whatever we want to in space. For the sake of argument, if one accepts such a goal, which model is more amenable to implementing it: the Apollo template or the Shuttle template?
If our goal is to “sail on the ocean of space,” we need a navy. Navies don’t operate with just one class of ship because one class isn’t capable of doing all that is necessary. Not all ships will look or operate the same because they have different purposes and destinations. We need transports, way stations, supply depots, and ports. In space terms, these consist of one to get people to and from space (LEO), one to get them to and from points beyond LEO, way stations and outposts at GEO, L-1, low lunar orbit, and to the lunar surface. To fuel and provision our space navy, we require supply (propellant) depots in LEO, L-1 and on the lunar surface. Ports of call are all the places we may go to with this system. Initially, those ports are satellites in various orbits which require service, maintenance and replacement with larger, distributed systems. Later, our harbor will be the surface of the Moon, to harvest its resources, thereby creating more capability and provisions from space. Reliable and frequent access to the entire Solar System, not one or two destinations, should be our ultimate goal.
By designing and building mission-specific vehicles and elements, the “Apollo” template forfeits going everywhere and doing everything. However, adopting the “Shuttle” model does not preclude going to Mars. In fact, I contend that to go to Mars in an affordable manner that sustains repeated trips, one needs the infrastructure provided by a space faring navy. Building a series of one-off spacecraft – huge launch vehicles to dash to Mars for expensive, public relations extravaganzas will eventually put us right back in the box we’re in now.
We have been arguing about the wrong things. It is the mindset of the space program that needs re-thinking – not the next destination, not the next launch vehicle, and not the next spacecraft. How can we change the discussion? First, we need to understand and articulate the true choices so that people can see and evaluate the different approaches and requirements. Second, we need to develop sample architectures that fit the requirements for “affordable incrementalism.” Finally, we need to get such plans in front of the decision makers. There is no guarantee that they will accept it or even listen to the arguments for it. But right now, they are completely ignorant about it.
A cost-effective, sustainable human spaceflight program must be incremental and cumulative. Our space program must continually expand our reach, creating new capabilities over time. Moreover, it should contribute to compelling national economic, scientific and security interests. Building a lasting and reusable space transportation system does that, whereas a series of PR stunt missions will not. The original vision of the Shuttle system was to incrementally move into the Solar System – first a Shuttle to-and-from LEO, then Station as a jumping off platform and then beyond LEO into cislunar space. We have the parts from the now retired Shuttle system and an assembled and working International Space Station. We can use these legacy pieces to build an affordable system to access the near regions and resources of cislunar space. In this new age of austerity, perhaps we will finally acquire the means to build our pathway to the stars.