eports are circulating that Alan Stern,
administrator for NASA’s
Science Mission Directorate,
currently is considering a plan to reorganize the robotic Mars exploration program in a way that would
the entire existing
program after the 2009 Mars Science Lab flight, including the Scout program, and replace
the lot with a Mars Sample Return (MSR) mission scheduled for launch about 2020. Such a reorganization would be a very bad idea.
Since its origin a decade ago, the existing fly-every-opportunity robotic Mars program has proven to be a brilliant success. It is producing unparalleled and ever-increasing science return, putting a robust communications infrastructure in place at Mars, and creating a proficient team competent to carry out ever more complex Mars missions. While many of former NASA Administrator Dan Goldin’s initiatives might have been questionable, there is no doubt that the concept of a sustained exploration program involving frequent launches of medium-sized spacecraft has proven to be far superior to the previous mode of attempting to explore a planet with one grand spacecraft every decade or so. The reorganization plan would thus abandon success – indeed, it would abandon the greatest success that NASA has to show for its efforts for at least the past decade.
Furthermore, in its stated objectives, the reorganization plan is much less supportive of the goal of the Vision for Space Exploration
enabling human Mars exploration – than
the existing program
. While, strictly speaking, no robotic precursor is required to enable human Mars exploration –
we now know considerably more about Mars than we knew about the Moon at the time of the Apollo landing –
the question remains: How could
our robotic exploration capabilities
best be used in advance to enhance
missions? The answer
they could be used to perform a sustained reconnaissance to identify the sites richest in
and resources for subsequent direct human investigation and exploitation
Mars is important for humanity’s quest for truth
because it is a critical testbed for the hypothesis that life originates from chemistry wherever appropriate physical and chemical conditions exist for a sufficiently long period of time. However, we now know that Mars had standing bodies of water on it at a time when there was already plentiful microbial life on Earth, and that there is and has always been natural transfer of unsterilized material between the planets. Therefore the discovery of microfossils on the surface of Mars would not in itself constitute proof of a second origin of life, since the lifeforms in question could well have come from Earth. Rather, to settle the question, we need extant organisms whose biochemistry can be examined. These, if they exist, can best be found in groundwater.
Thus the most important goal of the robotic program – if it is to be used to enable human explorers to achieve fundamental scientific discoveries – is to identify sites where bodies of liquid water can be found within practical drilling distance of the surface. This can best be done not with an MSR mission, but with a comprehensive scouting program involving orbiters, rovers, drillers, and possibly aircraft or balloons carrying ground penetrating radar.
If we consider prospecting for resources for supporting a human Mars base, this can be done best not by a couple of MSR missions that sample a site or two, but by a comprehensive reconnaissance program. Such a program might identify not only sources of accessible water, but also mineral ore.
Mars has had a sufficiently complex geologic history
to make the discovery of mineral ores of comparable quality to terrestrial commercial varieties a real possibility. While regolith that contains 15 percent iron oxide can be found anywhere on Mars, those who wish to make useable iron or steel would do much better with
deposits of material that is 90 percent or better. Similarly, while regolith that is about 40 percent silicon dioxide can be found anywhere on Mars as well as on the Moon, to make glass – let alone solar panels – silicon dioxide deposits or purity comparable to terrestrial quartz or sand are strongly desired.
If our goal really is to extend human civilization to other worlds, these and other useful minerals can and should be prospected for by the robotic program in advance of human Mars missions, so that our base site can be chosen appropriately.
Furthermore, even if one concedes considerable importance to the MSR mission, it is doubtful whether the programmatic path being considered in the reorganization plan is the right way to get there. If we do as that plan recommends and ground the Mars program for a decade, all the best people will leave the team, leaving the MSR mission poorly prepared technically, scientifically and politically.
It will be poorly prepared technically because instead of a live flight program that proves out key components, such as larger aerobrakes for larger landing systems,
and generates valuable experience over the decade preceding the flight,
the entire flight system would have to be designed on the basis of analysis by a team composed of a mixture of green and rusty personnel.
It will be poorly prepared scientifically because an ongoing program of increasingly potent orbital and rover reconnaissance missions that could have contributed much to identifying the best site for sampling would not have occurred.
It will be poorly prepared politically because instead of being integrated into an ongoing, funded and demonstrably competent robotic Mars exploration program, those who ask for funds to initiate Stern’s proposed MSR mission circa 2013 (assuming that they actually do so) will be starting from square zero. Furthermore, they will have to continue lobbying for funding for their project across the span of a decade during which no new discoveries on Mars are being made to maintain interest in the program.
Let us consider an alternative scenario. Rather than wrecking the current Mars program and hoping for the best, let us build on it. Let’s fly the orbiter in 2011, the Astrobiology Field Lab in 2014, and perhaps in 2016 an Advanced Science Orbiter, with instrumentation, data, handling and communications capabilities exceeding those of the Mars Reconnaissance Orbiter by all that a decade’s worth of technical progress can supply.
With the discoveries of the Astrobiology Field Lab and the Advanced Science Orbiter building justified excitement, NASA will be in a position – indeed it will have earned the right – to ask for a plus-up in funding
to add an
MSR mission into the queue. Then, while this is getting ready, rovers and drillers are sent to the most promising sites identified by the earlier missions to confirm their suspicions and gather and cache samples whose return will really matter. Then, with a well-practiced team using well-practiced equipment running the show, the MSR mission is flown and returns with samples providing ground truth to the data indicating the past or current presence of life on Mars. In addition to a truly worthwhile science return, such a mission would provide enormous and well-justified excitement of a sort that might give NASA the boost it needs to actually get a humans-to-Mars program off the ground.
There are those who would prefer to take funding from the Mars exploration program and use it for their own purposes.
One would therefore be nave to believe that a plan to abandon the existing Mars program has as its
purpose the goal of enabling a future MSR mission in 2020; funding some alternative project outside of the Mars program during our own time.
Yet, one must ask, is this what is best for the nation? Is wrecking NASA’s finest program really in the best interests of the space agency? Is this the way to support the vision of human exploration of other worlds? If our goal is to put our stamp upon the future by expanding civilization into space, is this really the way we should proceed?
The robotic Mars exploration program has proven itself to be a jewel not only in the crown of NASA, but of America; indeed it represents one of the great cultural accomplishments of contemporary human civilization. It should not be discarded lightly. Rather than breaking from it, we should build on it. That is the way to Mars.
Robert Zubrin, an astronautical engineer, is the president of the Mars Society
and the author of The
Case for Mars, Entering Space
and Mars on Earth.