Profile | Stephen Mackwell, Director, Lunar and Planetary Institute


The past decade or so has been a golden era for planetary exploration, with a mother lode of data pouring down from robotic probes like NASA’s Curiosity Mars rover, Lunar Reconnaissance Orbiter, Messenger mission to Mercury and the Cassini spacecraft orbiting Saturn.

Other nations are getting into the act in greater numbers. China, Japan and India are sending probes to the Moon and beyond, while the European Space Agency is preparing a Mars lander mission in cooperation with Russia.

Much of the data from these and other missions finds its way to the Houston-based Lunar and Planetary Institute (LPI), established in 1968 to support NASA’s exploration activities while fostering international scientific collaboration in this area. Then-U.S. President Lyndon B. Johnson described the LPI as “a center of research where scientists working in the sciences of space cooperate to profoundly affect the community’s knowledge of the universe.”

The LPI is managed by the Universities Space Research Association (USRA) under a cooperative agreement with NASA’s Science Mission Directorate.

For over a decade, Stephen Mackwell has guided LPI in carrying out research on the formation and evolution of all variety of celestial objects, from the Moon to asteroids to cosmic dust. This research is heavily dependent on data and samples provided by NASA and other space agencies over the years.

Mackwell acknowledges there will be challenges in the years ahead in the form of tight budgets and high mission costs that could slow the flow of data that is the lifeblood of LPI. But he also sees a solar system rich with opportunities for discovery.

Mackwell spoke recently with SpaceNews correspondent Leonard David.

How would you characterize the state of space science in the United States?

We have an outstanding robotic program in space. I think we have a severely underfunded human program. You’ve got this push me/pull you between the administration and this current, fairly toxic environment in Washington. We’ve got competing political goals even in the space science program. Because of some rather large things in the budget — the James Webb Space Telescope is a good example — money has to be moved around for periods of time to support those big projects. That money has to come from somewhere … so you slow down the cadence of observations and measurements, and missions going out into the solar system.

Can technology help curb costs of planetary exploration?

I think part of the solution is thinking creatively about technologies to make missions possible to destinations that are hard to reach and expensive to reach.

Can you give any examples of technologies that are promising in this regard?

The Advanced Stirling Radioisotope Generator is potentially a good step along that line … but that is not the only solution. Things like solar panel design, using ion engines, decreasing the weight of spacecraft — there are technologies out there that can really enable us. There’s a lot of really good science that can be done, particularly if we’re creative with our technology and we don’t get too risk averse with what we’re flying.

Are you encouraged that the U.S. Department of Energy has resumed low-level production of the plutonium fuel used for NASA’s deep-space missions?

That’s great news. But it’s not clear exactly how much they will be able to produce. From what I understand, it seems it will be challenging to produce a kilogram and a half a year unless they use more than one reactor to do this. There’s certainly enough feedstock. It’s really a question of whether there’s interest on the Department of Energy’s part to continue this process and whether it will be within the range that NASA would like to see. We’ll see what happens.

Do you have concerns about how the current budget climate will impact future robotic exploration?

It’s highly unlikely we’ll have a stable budget going forward. That’s why a one-size-fits-all plan for space science missions doesn’t work. You can’t always build a Christmas tree. You don’t always want to have a multibillion-dollar mission that sucks all the oxygen out of the program. You’ve got to have a range of different missions so that things are always going on. You want a diversity of mission sizes that maintains your community, keeps them engaged and viable through budget cycling.

There’s a need to make sure you have a spectrum of different things you are doing. Stepping back, there are major differences ahead in solar system exploration in a broader structure. Entrepreneurial-type characters like Planetary Resources and Golden Spike have come into the scene and are looking at and evolving different business models. That’s a real change in the way things happen.

Is NASA’s planetary exploration program too Mars-centric?

There’s a lot more to the solar system than just Mars. But if you were to pick a place where there is a probability of finding microbial life, and close to our current capabilities, then it’s going to be Mars. You can talk about Jupiter’s Europa as much as you like. But any mission first sent there will not detect life — it will only set us up for an ultimate mission to see whether there’s life in the subsurface of Europa. So Mars is the place to go right now if you’re looking for life. Now of course looking for life doesn’t have to be your mantra for exploration. It has become that.

What other objects should space agencies be paying more attention to?

It seems to me that we’ve got bodies out there we should study. But we’re not studying them because we’ve got ourselves really hooked into this business of looking for life elsewhere.

The whole idea of comparative planetology kind of went through a hiatus for a while, but it’s now back, fast and firm. Why did Earth and Venus take such different evolutionary paths? Uranus and Neptune look to be very different objects. If you want to understand the kind of exoplanets that we’re seeing, then you better understand what we’ve got going on in our own solar system.

Every time we go to a planetary body and we take a closer look we find a diversity of features and structures that we never anticipated. We always find processes that we don’t understand in terms of Earth-based eyes.

How do you characterize the international scene in terms of exploration?

There’s been a huge pulse of activity — the Chinese, the Japanese, the Europeans and the Indians going to look at the Moon. The Russians are starting to get serious again.

In that vein, how well is the United States working with other nations?

In a conversation with an engineer from the Indian Space Research Organisation, he kind of joked that they owed a great debt to the U.S. and to ITAR [International Traffic in Arms Regulations that govern certain U.S. technology exports]. If it hadn’t been for ITAR they wouldn’t have developed their launch capability. It’s sort of true. What ITAR has done has limited the United States’ ability to market internationally what we have developed in this country. That has provided a justification or a need for other countries to develop their own launch capability. Through ITAR we’ve enabled other nations. They still need technology and they couldn’t get it from us. We can’t market our wares. So that’s meant that other countries are cooperating with each other. We’re kind of being left in the dust. We’ve hog-tied ourselves, and other countries are stepping up.


Are there any other worrisome trends that you’re keeping an eye on?

The things that worry me most, I guess, are how wasteful the current environment is. We have continuing resolutions that force us to spend bucket-loads of money on something that’s already been effectively canceled. There’s the politicalization of what NASA is doing with relatively limited budgets, pushing us in directions that aren’t necessarily the optimal direction to go in terms of making use of those limited resources. I think the overall budget issue is workable, but there are things that are diverting us from the right path forward.

The other part of the problem is leadership. NASA needs strong leadership, not just to look after the NASA family but also to represent itself through the Office of Management and Budget and the Office of Science and Technology Policy into the White House. We need to have people in charge who understand what it is that NASA is about and be able to make the case for why this is important.