Category Archives: NASA

NASA, Space

A Diary in Space

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I recently read a fascinating book – a diary of a man who spent about a year on a space station. In his journal, he expresses his excitement about learning to live and work in space. He’s proud of the opportunity to represent his country, and he enjoys sharing his accomplishments with international visitors to the crew. He learns to appreciate the automated systems on the next-generation spacecraft sent for resupply. He grows – and eats – plants in space. He worries about ennui, and at one point enjoys playing a practical joke on ground control with a monster mask. He particularly enjoys exercising on the treadmill and observing earth’s geology. His dream is to perform a spacewalk, and he achieves that goal.

You might think I’m referring to astronaut Mark Kelly’s hashtag-YearInSpace. But I’m not.
The man is Valentin Lebedev, and the book is “Diary of a Cosmonaut.” The mission is Salyut-7. The year is 1982.

I found the book quite interesting to compare to recent events in spaceflight. For one thing, the similarity between Lebedev’s Soviet mission and Kelly’s #YearInSpace was uncanny. I’m not even kidding about the monster mask – it came up to the Salyut station with French cosmonaut-visitor Jean-Loup Chrétien. Lebedev’s translator wrote the phrase “learn to live and work in space” even then, back in the early 1980s.

What sticks in my head, though, are the ways the Salyut-7 mission differ from a contemporary NASA International Space Station Expedition. In 1982, the Soviet Union was not able to communicate with their stations over the full length of the orbit. As a result, the two-cosmonaut crew had a much greater degree of autonomy than NASA affords a modern mission. Lebedev and his commander made their own decision to extend their spacewalk. They often decide which scientific experiments to do. They determine much of their own exercise regimen, and they arrange the interior of their station to their liking. These are behaviors that NASA must learn – re-learn, really – if they truly want to send humans out to “live and work” beyond Earth orbit. Especially at Mars, where real-time communication back and forth with mission control is not feasible.

This is not to say that everything was better on Salyut than on ISS. At one point, the two cosmonauts smell something burning – fire is an immediate existential danger on a spacecraft. They’re out of communications with the control center, so the cosmonauts grab a fire extinguisher and go hunting for the source on their own. They find the source of the smell – a component overheating – and take care of the problem. Then, they decide not to tell ground control. Wouldn’t want to worry them! In another instance, the cosmonauts are rearranging supplies and equipment on their station when they find that a refrigeration unit won’t fit behind a panel. So: they get out a saw, and start cutting the metal panel. (Somebody thought they would need a saw?!) I’m all for astronauts learning to build and repair things in space, but this activity leads the cosmonaut to make the logical complaint. Metal shavings float everywhere, and one goes in his eye. (Fortunately, his companion is able to remove it, ending that cringeworthy episode.)

There’s a lot the modern NASA could learn from these programs of the past: they were steeped in ingenuity and piloted by independent souls who really had the Right Stuff. But there’s also a lot we have learned: to plan thoroughly, to account for then-unknown contingencies, and to sustain a human presence in space for continuous years. What amazes me most, though, is how, over thirty years later, the broad architecture of life on a space station and the research program in space is the same. We need a next step. Centrifugal gravity, closed-loop life support, agriculture in space: We know the kinds of technologies we need to do to truly enable life and work in space. If only NASA would do it.

NASA, Science Fiction, Space

What drives me nuts about “The Martian”

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“The Martian:” Yeah, Martian dust storms are nothing. Yeah, Rich Purnell could’ve explained his maneuver to the NASA top brass with about six acronyms and the phrase “gravity assist.” Yeah, real-life-JPL has almost nothing to do with human space exploration. And yeah, that blow-up-the-Hermes thing is a completely harebrained and terrible idea.

I’ll give the movie a pass on all those counts, because it’s a good story, it gets most things right, and it puts technical problem-solving front and center. But here’s what really drives me nuts about “The Martian:”

“The Martian” highlights what NASA must do, but is not doing, in order to get people to Mars.

The Hermes
The Hermes

NASA must build interplanetary transfer craft optimized for deep-space travel, like the Hermes, not single-use capsules designed mostly for reentering Earth’s atmosphere like Orion.

NASA must invest significant research and development effort into “in-situ resource utilization,” such as the robotic manufacture of the fuels and propellants the MAV uses for Mars ascent.

NASA must develop closed-loop life support systems, like Mark Watney has in the water reclaimer and the oxygenator.

NASA must learn to grow food on Mars, instead of trying to send every supply with their astronauts in a single mission.

NASA must build vehicles that provide their crew with artificial gravity, by rotating, to counteract the bone loss effects of long-duration spaceflight.

NASA must learn to let its astronauts solve their own problems when they are twenty light-minutes away from Mission Control.

Most of all, NASA must try a lot of ideas, and they must be willing to see some of those ideas fail, in order to accomplish their ultimate goals.

What astronauts on Mars should be doing
What astronauts on Mars should be doing

Right now, NASA’s plans for getting people to Mars revolve around a series of activities designed to “learn how to live and work in space.” These activities include astronaut Scott Kelly’s hashtag-YearInSpace mission and the Asteroid Redirect Mission.

Commander Kelly’s mission has the goal of learning how the human body responds to a long duration spaceflight. At the end of his mission, Kelly will be tied for the fifth-longest duration spaceflight. We already have much experience with long spaceflights. Our friends in Russia have even more. So we already know pretty much everything that’s going to happen to him. What’s more, we know ways to mitigate those adverse effects. We need, for example, something to simulate gravity. Like a spacecraft with a centrifuge. That’s a solution science fiction – including “The Martian” – has taken for granted for decades, though NASA has no obvious plans to build true long-duration space vehicles for its crews. They will go to Mars floating in the cramped zero-g environs of an Orion capsule.

NASA also isn’t looking seriously at growing food to keep their crews fed in space. At a conference last March, I learned that all the Mars exploration reference missions involve taking all the food the crew needs for their entire travel, exploration, and return mission. That takes a huge amount of payload mass. Mark Watney did a much better job – and saved a lot of weight – by turning a few potatoes into food for a year. He got fresh vegetables, something his colleagues on the Hermes didn’t even have. Rover data shows that plants could grow on Mars, and creating a spacefaring civilization obviously depends on our ability to feed astronauts – so, again, why not look at the obvious solutions?

The big idea that “The Martian” demonstrates is human ingenuity and problem-solving. To NASA, though, that’s a problem. NASA doesn’t want astronauts tearing components apart and putting them back together like Mark Watney does. They want to have astronauts follow a checklist that has been tested, verified, and validated on the ground in several dozen ways. That philosophy is so pervasive in NASA that agency officials talk about how they need the Asteroid Redirect Mission to “test” solar-electric propulsion – a technology that NASA itself has been using in flight missions since 1998. If NASA really wants to go to Mars, it’s going to have to learn to be more like “The Martian:” being willing to take risks, try new ideas, and give its astronauts leeway to make decisions.

That’s what drives me nuts about “The Martian.” It depicts the space program that I’ve been hungering for for thirty years…and I’m afraid I won’t see such a thing for thirty more, at least.

NASA, Science, Space

Space programs are not ambitious enough

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This week, NASA announced the selection of nine instruments for a proposed mission to Europa. Europa is probably the best place we know about to find alien life, and the discovery of alien life would surely be an achievement rivaling the moon landing in NASA – and human – history. I have an issue with the thinking presented by NASA in its press releases, though. Agency spokespeople say things indicating that the purpose of the Europa mission is to determine whether or not Europa “could be habitable.” The exact phrase on the web site linked to above is that this mission is part of “our search for oases that could support life” (emphasis mine). That’s not what I want from a mission to Europa. Probes to outer planets come decades apart, so I want to get as much done in a single shot as possible. What I want is to determine whether or not there is life on Europa.

The important difference between those two statements – determine whether Europa could support life and determine whether Europa has life – betrays a slight difference in ambition. I want the big-risk, big-reward activities and objectives of a true moonshot. NASA is hedging its statements, and lowering the bar of its mission goals.

I’m coming to believe that the statement about Europa Clipper’s objectives is symptomatic of a general lack of ambition in NASA’s modern thinking. You can see it in other statements the agency makes: Mars Science Lab Curiosity‘s mission was to determine whether Mars, at some point in its past, could once have been an environment that supported life. The oft-repeated purpose of the “proving ground” activities in the human spaceflight program’s “Journey to Mars” campaign is to “learn how to live and work in space.”

I don’t want to do those things. I want to find out if there is life on Europa; similarly I want to find out if there is (or was) life on Mars, and I want people to live and work in space.

Ironic that a space program – of all things – would lack ambition, isn’t it?

You might think that this is just the public relations spin. NASA is trying to manage expectations, so that they know they can achieve the first objectives of any mission and claim success immediately. Then they can parade that success in front of Congress, while the scientists go after their real scientific objectives in the “extended mission.” But I think the underlying philosophy here is penetrating beyond the publicity level into the actual mission design. It’s easy to find statements from scientists, engineers, and NASA spokespeople that Curiosity couldn’t actually find life on Mars unless that life walked in front of its camera and waved hello. To me, those statements beg the question: why not? We sent a nuclear-powered jetpack-landed laser-toting robot all the way to Mars, why wouldn’t we put some instruments on it that can identify basic things like amino acids? Similarly: NASA sends a probe to Jupiter approximately once per decade (and slowing). Since that rate keeps dropping as time passes, why wouldn’t we try to answer the big questions as soon as we can?

The way NASA now formulates its missions, I can just imagine a variation of Kennedy’s famous moon landing speech: “Our nation should dedicate itself to the goal, before this decade is out, of lifting a man five inches above the surface of the Earth. If that is achieved, this mission is a complete success. As a stretch goal, we might have that flight go to the Moon.”

The great thing about opening up the ambitions of our space program is that it would enable engineers to implement known solutions to the problems we face in space. For example: we know that humans have health problems after spending long periods of time in microgravity. Do we need to keep answering the question of whether or not humans have health problems after spending long periods of time in microgravity? Or can we instead think about the details of building spacecraft that spin to provide artificial gravity? Similarly, we know that there are extreme logistical challenges in sending people to Mars. Do we think about long a mission we could run given the amount of food we can send up with our astronauts, or can we think about the details of having them grow food on Mars?

The difference between those questions is the difference between “learning to live and work in space” and “living and working in space.”

It’s also the difference between the space program we have, and the space program we imagine.

Concepts, NASA, Science Fiction, Space

How to Get to Mars

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NASA wants to go to Mars. Great!

The approach, as the agency has been publicizing with fancy graphics like the one below, seems to consist of the following:

NASA’s tentacles travel to Mars
  • Send astronaut Scott Kelly to the International Space Station for one year, to learn about the effects of zero gravity.
  • Perform the Asteroid Redirect Mission, moving a near-Earth asteroid into lunar orbit, to prove that solar electric propulsion works in space.
  • Assemble a Mars transfer spacecraft in distant Earth orbit out of components launched on the Space Launch System.
  • Pack everything astronauts need for a round trip to Mars on the new spacecraft and send them on their way!
  • Keep the spacecraft in space for future trips to Mars. Bring the astronauts and supplies back and forth separately.

Not that these aren’t good brainstorming ideas, but they are not how I would get to Mars. I am too confident and impatient for this plan.

For one thing, we can probably skip this one-year mission. In fact, NASA, I can help you out by zipping straight to the conclusions: Being in zero gravity for a year results in bone loss, muscle atrophy, a compromised immune system, radiation exposure, and changes to the shape of the astronauts’ eyes. We know all that already. Similarly, we already know that solar electric propulsion works – quite effectively, robustly, and scalably – in space. Commercial satellites are flying solar electric propulsion right now, with more on the way. Heck, NASA itself has been flying solar electric propulsion, on missions like Dawn, since the turn of the millennium! Nothing needs proving here. We can take the known technology and use it.

Now, assembling a Mars transfer spacecraft, sending it onward, and reusing it for further exploration – that I like. Here is how I would do it.

First, get one of the companies developing solar-electric propulsion satellites to build a number of spacecraft buses. They will probably run a few tens of millions of dollars each, and they can ride up to space on Falcons, Arianes, or Atlases. (That’s bargain basement stuff for NASA!) Then, tie them together. All I really want are the propulsion systems. Each spacecraft has a propulsion system with something around 10 kW power, and NASA wants to get up to around 100 kW to go to Mars. So, by my rocket science calculations, we need…ten satellites. Or maybe, if we strip out all the telecommunications payloads that these satellites usually carry but I don’t care about for this application, maybe we can get the number down to five-ish.

Four of 'em stuck together
Four of ’em stuck together (with obligatory blue ion engine exhaust)

Somebody would probably have to do some thinking about the best way to support all these stuck-together satellites. Maybe a truss of some kind. But I’m not too worried about that, because NASA has two decades of experience building modular things and sticking them to trusses in space. They can just do what they do best, using their own well-proven techniques.

Now we need a place to put our astronauts. Preferably a place that has some accommodations for solving the problems that Scott Kelly will be confirming. Many of the major physiological issues with space travel have to do with being in zero gravity. Too bad our Mars transit vehicle can’t bring gravity along with it.

Oh, wait! Science fiction knows the answer. It’s known the answer for decades! Spin the spacecraft. The astronauts get to live with a force akin to gravity, pulling them outward along the spin axis.

But building a giant ring-ship takes a lot of time, effort, energy, and resources. I have something different in mind. Something simpler:

My Mars transit vehicle is finished!
My Mars transit vehicle, finished!

On the right, that’s supposed to be an inflatable, cylindrical habitat. (Inflatable things would be terrific for space construction, because they only need a small launcher. Since everything on my vehicle is made of small components, we can launch them once a month instead of once every two years, if they needed a super-heavy launcher like SLS.) This inflatable habitat is tied to the central propulsion core by tethers, or maybe trusses of some type. The astronauts would feel “gravity” pulling them toward the right-hand side of this image (and a little bit downward, because of the thrust). On the left is a dumb counterweight: I’ve drawn it to evoke the empty upper stage of a rocket. It could maybe be long-term storage, but its main purpose is simply to be dead weight to make the spinning easier. The whole vehicle would rotate about the thrust axis, rapidly enough to give the crew at least lunar or martian gravity levels. (The illustration isn’t to scale!)

I’d do one last thing before I send this to Mars with a crew. I’d pack the transit vehicle with enough food, water, and air to get the astronauts to Mars, and for their surface stay.

Not enough to get back, though.

Instead, I would bring seeds. When the astronauts land on Mars, the first thing they will do is become high-tech space farmers. They are going to grow all the food for their return trip on Mars’ surface.

Why would I want to do that? Well, for one thing, seeds are smaller and less massive than full-grown food products. They are probably less expensive – in an energy sense – to get to Mars than those food products would be. Then, on Mars, we can get water and carbon dioxide from the atmosphere, to fuel plant growth. So, over the whole mission, I’m actually saving time and money. There’s also a second reason, one I find more compelling. What’s the point of this whole endeavor if we don’t come out of it knowing how to colonize and explore other planets, and keep colonizing and exploring them? Learning to use the resources on other worlds is fundamental to the future of space exploration. We know Mars has water, we know it has oxygen, and we even know that we might be able to grow crops in its soil. We should focus on that idea and advance it. In other words, I think that – both pragmatically and philosophically – it would be shortsighted and silly to attempt Mars exploration using only what supplies we can bring from the Earth.

We need a space program that focuses on developing the technology to use the resources on Mars to support further Mars exploration. We need to do this in a modular, reusable, scalable manner. We need to make sure our astronauts – no, our pioneers – have the tools, the materials, the infrastructure, and the autonomy to solve their own problems. In other words, we need to stop thinking about how to put a few guys in spacesuits on Mars, and stop thinking about how to have astronauts do science on Mars, and instead think about how to colonize Mars. That requires a lot of little things to come together, with more than a few big things in the mix as well. But, for the most part, we have the technology. We’ve had it for my entire lifetime. We need a space program with the right stuff to use it.

That’s how to take a journey to Mars.

NASA, Space

Space to get excited about

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Last month, NASA repeated an accomplishment they first checked off in 1964 – with some few improvements hardly worthy of the intervening half-century. But tomorrow morning, assuming the weather is a “go,” we will get to see a space travel event that has me far more excited. SpaceX is going to launch a rocket…and they’re going to turn the first stage around from high altitude and hypersonic speed to land on this:

SpaceX drone barge

in the Atlantic Ocean.

I love this.

I love this because of the technical meaning of the capability: being able to reuse a rocket would be seriously cool. It has the potential to alter forever the economics of spaceflight. And it’s not as crazy an idea as you might think at first – SpaceX has actually pretty much done it already, albeit without the barge underneath the landing rocket.

But I also love this because of what the event represents! Elon Musk estimates a 50/50 chance of success. SpaceX is trying this because nobody has tried it before. They are trying it because there’s no way to convince people it’s possible except by doing it. They are being incredibly ambitious, and they are willing to accept failure in order to learn from it.

In an industry increasingly defined by incrementalism and risk aversion, SpaceX recognizes that sometimes reward comes from risk. They are truly innovating; trying things that are new. It seems that while NASA’s human spaceflight programs once had the “right stuff,” they lost it in bureaucratization – but the “right stuff” didn’t vanish. It just moved – to the robotic explorers like Curiosity or New Horizons and to the “new space” companies like SpaceX.

Best of luck to the SpaceX team tomorrow. I know that even if you don’t succeed, you’ll be proud of your achievements and you will try again. But I’d bet you’ll see that first stage again!

Concepts, NASA, Skepticism, Space

Back to the Future

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This week, NASA launched the Orion spacecraft on a test flight. I have a conflicted viewpoint about this event. To me, Orion is both exciting and deeply disappointing.

On the one hand, Orion is NASA’s first entirely new spacecraft for human crews in over twenty years. There have been only seven in American history: Mercury (first successful flight in 1959), Gemini (1964), Apollo (1966), Skylab (1973), Space Shuttle (1981), Space Station (1992), and Orion (2014). Those dates have been getting unacceptably distant from one another, and it is wonderful to see NASA getting its game back on. Test flights are NASA’s business. The agency is supposed to operate in the proving ground of technology. I want to see it doing new things, and the Orion flight was a reasonable first step towards NASA getting back to its roots. Those roots, after all, were triumphant!

On the other hand, though, Orion falls far short of what NASA could, and should, do. The spacecraft is an improvement over the last capsule NASA designed – the Apollo Command Module – but it is an incremental improvement rather than a revolutionary one. As an example, one of the technological advancements NASA has been touting about Orion is its glass cockpit. But this is the era of the iPad: in such a mass- and volume-constrained environment as a space capsule, the glass cockpit is simply not innovative – it is obvious. (For examples of innovation in space vehicles, try inflatable habitats, rockets that fly back to their landing pads or crew shuttles that could land at any normal-sized airport runway.) To make matters worse, not only is Orion an incremental step in capability from the early ’70s, but its development is horrendously stretched. For reasons that are political, programmatic, and cultural, rather than technical, the next flight of Orion will be in 2018. A human crew will not use the capsule until after 2021, at which point it will be almost a decade old itself.

I think the most bitter disappointment is the concept of what Orion will do when it finally does have astronauts on board. The current plan is to build the world’s biggest rocket, the Space Launch System, and use it to send an Orion crew to asteroids and Mars. I’m all for visiting those places, but the “giant rocket with space capsule” architecture – the architecture of Apollo – is a recipe for one-shot visits to other worlds. After the first astronauts return from such “flags and footprints” missions, there is a very strong risk of program cancellation. I don’t want to see our space program cancelled.

An Orion capsule riding a Space Launch System rocket is not even close to how I would design a sustainable, long-term space program. A much better approach is to use many different spacecraft, and specialize them for individual purposes. Think of the Apollo Lunar Module: it was a flimsy, silly-looking vehicle that was exactly suited for the prospect of landing and taking off from the Moon’s surface. Instead of building on Apollo and Space Shuttle heritage to make an “all-purpose” space capsule, I would like to see NASA lean on its Space Station experience to design a set of interplanetary transport spacecraft. These vehicles would stay in space for their whole lives: we would assemble them in space, launch them out of Earth orbit rather than from Earth’s surface, and we’d never use them to carry astronauts up from and down to the ground. Whenever they need more fuel, we’d send only the fuel up to them – not a whole new vehicle. When we need to rotate astronaut crews, we could always hire SpaceX.

That sort of multi-vehicle concept offers some big advantages. First of all, it’s much more flexible than giant, infrequent, one-shot missions. Second, it’s far more efficient and cost-effective. Think about this: 20% of Orion’s mass is its heat shield, a component only needed for the last ten minutes of its mission. If Orion is returning from Mars, then that means our Mars return rocket needs to be huge in order to push that heavy heat shield on its half-year-long journey back to Earth. And if the heat shield and Mars return rocket need to be huge, then the Earth departure rocket needs to be enormous. Instead, though, we could forget sending the heat shield to Mars in the first place. Forget having the vehicle that goes to Mars also be responsible for landing on Earth. When the astronauts come back from Mars, you just send a little rocket with a little capsule into Earth orbit – just enough to bring the astronauts to the ground. The lightweight interplanetary spacecraft stays in space.

In 2011, when Congress ordered NASA to begin work on the Space Launch System, internal NASA studies came out that agree with my assessment. Multi-vehicle approaches that we can re-fuel and re-use in space are more efficient and cheaper than SLS. They will also get astronauts to other worlds much sooner. Most importantly, such approaches won’t be reliant on one-and-done missions. They will be much more likely to keep our explorers in space.

That is why, while I applaud NASA’s successful demonstration of the ability to launch new vehicles, I hope the agency moves on quickly from Orion, and begins work on a new fleet of exploration vehicles to stay in space.

NASA, Space

Space fleets

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A couple days ago, an article on NASASpaceFlight described an architecture of vehicles Bigelow Aerospace allegedly presented to NASA. Bigelow is a company developing inflatable space habitats – they’ve launched a few technology demonstrators already, and an inflatable module is set to go up to the International Space Station in the near future. Apparently, they presented a series of modular, inflatable habitats along with a set of space-based utility “tug” vehicles designed to carry out various support functions.

I like this general idea – it fits in with my own vision for a successful space exploration architecture. Specifically, rather than a multipurpose vehicle that must shuttle up and down from Earth’s surface, I want to see a set of many vehicles highly specialized for space exploration purposes. Those vehicles should be native to the space environment – designed never to enter the Earth’s atmosphere. They might even be built in space in the first place.

It would be really terrific to see a company ready to provide that space exploration fleet.

NASA, Politics, Space

A difficult question for space advocates

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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!

NASA, Space

Antares and tiny satellites

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This weekend was full of excitement for commercial space fans. Orbital Sciences Corporation launched the Antares rocket, making them only the second private company to put a vehicle into orbit. Like the SpaceX Falcon 9, Antares is intended to carry cargo to the International Space Station. Antares is cool for a couple of reasons – partly because it represents a further gain in the United States’ launch capability, but more notably because the target market for Antares commercial launches are smaller spacecraft than the usual several-thousand-ton geosynchronous birds.

Smaller spacecraft are particularly cool because – since their design, fabrication, and launch costs are lower than big satellites – satellite manufacturers are more willing to take risks with their design. I don’t mean “risks” to imply that these spacecraft are unsafe. I mean that they are not quite as tried-and-proven. In other words, they can be more cutting-edge. More innovative. More likely to push the envelope.

In that vein, what I find most exciting about the Antares launch is that the vehicle carried three NASA CubeSats specifically designed to puncture the conventional wisdom about how conservative spacecraft designs need to be. They are called “PhoneSats,” and what makes them special is that their flight computers are off-the-shelf Android cell phones. Their on-board avionics software is an app.

http://www.nasa.gov/directorates/spacetech/small_spacecraft/phonesat.html
PhoneSat 1.0 (from nasa.gov)

The idea behind these CubeSats is to test how robust spacecraft really need to be. Commercial spacecraft engineers design huge margins into their vehicles. We tend to be very careful and conservative. But since many spacecraft last well longer than their quoted design lifetimes…maybe we’re too conservative. The PhoneSats will help answer the question: If we just get commercial computer hardware and design a system that works – without so much conservatism – how long will it last in space? Maybe it will operate long enough to complete its mission.

If the PhoneSats stayed in orbit forever, they’d be likely to burn out. Their Android processors and flash memory would fail under the onslaught of cosmic rays. But, at under $7000 each, maybe even the short mission of these satellites would make them competitive with the longer-lasting multi-million-dollar vehicles.

I’ll be very interested in the results of the PhoneSat project!

NASA, Science, Space

Marswhelmed

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So, the Mars Science Laboratory “Curiosity” has discovered evidence that, about three billion years ago, the environment on the planet Mars could have supported Earth-like microbial life. Some news outlets (including the MSL Twitter feed) are billing this discovery as the accomplishment of Curiosity’s mission.

I have a confession to make.

I don’t really find this discovery all that exciting.

The MSL team’s discovery is a confirmation of a long-expected hypothesis. (Indeed, with the number of planetary environments out there, it would be statistically silly to think that Earth is the only life-supporting place!) It’s valuable to know, and it’s important to the scientific method to rack up such confirmations even when we’re as sure as we can be, but it doesn’t exactly have the same allure as striking out into the unknown. I think the spirit of exploration is important to maintain in our space programs, because brand-new missions and discoveries are what keeps space exploration in the public eye. After all, a recent study shows that not only do most Americans want to see exploring Mars as a national priority, but most Americans want to see a human mission to Mars and three-quarters of Americans want to see the NASA budget doubled. I am confident that the dramatic landing of the Curiosity rover, with its brand-new mission architecture, has something to do with that enthusiasm.

There’s also something I find slightly foreboding about Curiosity’s confirmation. In 2011, the National Research Council’s Planetary Sciences Decal Survey of Solar System exploration listed and prioritized the objectives of our planetary science program for 2013 through 2022. This is a study done every ten years to identify which of the flagship-sized missions NASA should fund, design, and launch in the coming decade. First on the list for 2013-2022: a mission to return samples of Martian rock and soil to Earth. The announced “Mars 2020” rover is in line with that objective.

I’m going to go out on a limb and predict the conclusion sentence of scientific findings from a Mars sample return mission:

Chemicals and minerals present on the surface of Mars indicate that ancient Mars may have included wet environments able to support Earth-like microbial life.

In other words, I don’t think a Mars sample return mission will give us any dramatically new information that we didn’t already have from MSL, MER, MRO, or any of the Martian samples we already have. See what’s got me worried? I don’t think we’re going to actually discover life – in fact, I would be very surprised if the 2020 rover included any instruments actually capable of recognizing a Martian if it walked right up, poked the rover with a Martian stick, and walked away. (Curiosity doesn’t!) I am afraid that we will put this rover on the Red Planet in 2020, cache a sample, retrieve the sample in 2030, and the public response will be, “wait a minute, we spent two decades confirming what we already knew in 2013? Come on, space program…where’s my jetpack?”

A Mars sample return mission would be a triumph…for the niche sub-field of Martian geochemistry. I don’t think it would have the sort of broad scientific and public impact that we should expect from a flagship-scale mission. Basic research science plods along, making incremental improvements in understanding and slow-but-steady progress. NASA should be sticking its neck out, thinking big, and going for the most challenging – and rewarding – missions. Instead of looking for environments that might have been habitable three billion years ago, we should be looking for actual life.

You see, even before MSL’s discovery, we already knew of the existence of a watery, potentially life-supporting environment. Jupiter’s moon Europa has an icy crust with a subsurface water ocean beneath. The ocean is warm enough to be liquid, because of the energy input from Jupiter’s tides. And scientists have found that that ocean contains lots of salts and minerals – and even organic (carbon-containing) compounds. Liquid water, energy sources, and chemical building blocks: everything an Earth-like life form needs! The main difference between Europa and Mars is that, while we’ve been able to observe the desolation of the Martian surface for decades and know that we could only expect to find evidence of ancient microbes, we have no idea what’s under the Europan ice sheet. It could be nothing…but it could also be life as rich and complex as what we find, on Earth, under Antarctic ice, in sealed cave systems, or around hydrothermal vents. Unlike Mars, where we have been forming preliminary conclusions for years, we won’t know until we get something under that ice layer. That’s the kind of exciting exploration work that I want to see from my NASA flagship missions.

The Decadal Survey did recognize the potential for alien life on Europa. Its executive summary says that “the second highest priority Flagship mission for the decade 2013-2022 is the Jupiter Europa Orbiter” but notes that “that both a decrease in mission scope and an increase in NASA’s planetary budget are necessary” to fly a mission to Europa. Personally, I’d prefer to discover alien creatures within my lifetime…but I don’t make policy or control the purse-strings. So, instead, off to Mars we’ll go again.