Category Archives: Space

NASA, Politics, Space

President Obama spells out his NASA vision

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While I would love for President Obama to give Twitter the blind eye I think it deserves, today he used the blip medium to take (moderated) questions from the public. One of those questions was about the future of the space program and NASA. Here is the President’s response (courtesy of space.com):

I am so happy to hear Mr. Obama say this! I am totally on board with the idea that NASA should be sticking its neck out doing unproven things and pushing the frontier outwards.

The most unfortunate thing for NASA’s budget and NASA’s role over the past year or two has been how poorly the Administration articulated this vision. They let the media run with headlines about how “Obama killed the manned space program,” instead of making the story one about smart investments in proven methods and accelerated research into new technologies to get our astronauts to really exciting destinations that the Apollo veterans could only imagine. You know…buy Falcons  to get to LEO while NASA figures out how to get to Mars.

The President could make an even stronger case – I think that if he wants to advocate a “Manhattan Project” to fight climate change, push the capabilities and cost-effectiveness of medicine, engineering, and agriculture, and provide lots of jobs, industry opportunities, and infrastructure investments, he ought to announce a program to establish a self-sustaining human colony off the Earth. But I think he hit some major points for a sustainable space policy in his answer above. He also made the strongest, most unambiguous statements I’ve seen yet about the purpose of NASA and the destinations the agency should target.

Sadly, Congress is now subjecting NASA to both the Death of a Thousand Little Cuts and the Death of Stupid Over-Specified Directives. If the American manned space program ends, it will be because Senators like Orrin Hatch and Bill Nelson look at NASA more as a jobs program for their districts than as a vehicle for realizing our nation’s highest ambitions. Hatch in particular – the Ares program should have been cancelled and the heavy-lift vehicle mandated by Congress is a bad investment that will take NASA nowhere.

Maybe, just maybe, the Obama Administration is going to do a better job of putting their space policy message out in the coming budget fights. And then maybe, just maybe, we will end up with what the Augustine Commission called “a space program worthy of a great nation.”

NASA, Space

This is really amazing and if you haven’t seen it already you need to

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Space Shuttle Enterprise on the launchpad

Click the image above to go to a Space Shuttle program retrospective photo gallery put together by the photographer formerly behind the Boston Globe’s Big Picture blog. It’s amazing. (I never knew that Enterprise made it to the launch pad! And in Vandenberg!)

Some of the pictures give a wonderful glimpse into the history of this storied program. And some of them are actually heartrending to someone like me. Especially when I got up to the picture of Christa McAuliffe – because I think I have actually sat in that chair. I remember thinking about how I was sitting in a seat that many astronauts had spent time in, and how prominently displayed in the Space Vehicle Mockup Facility’s huge open space are giant versions of the Apollo 1, STS-51-L, and STS-107 mission patches.

I particularly like the shot from Vandenberg, above, the snap of Sally Ride, and the image of the cosmonaut peeking out from Mir – among all the classics like Bruce McCandliss floating in space and the wonderful new shot of the Shuttle docked to ISS.

Count on me to write something else for the end of the Shuttle program soon…

NASA, Politics, Skepticism, Space

The Drive

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Imagine, if you will, that a US government agency invented the automobile.

And for forty-five years, nobody else but the National Automobile Sales Agency produces any cars in this country. Not because of any particular regulation, you see – but because cars are complex machines that require precision workings and careful construction. They are expensive and require a significant investment in infrastructure. So, not everybody has a car, though plenty of people out there want one. And those people have to buy the cars developed by the US Car Program. Imagine. If you will.

Now suppose that the first batch of cars that the National Automobile Sales Agency were some real hot rods. They could tear all over the place, they looked downright sexy, and they inspired envy in all but the most curmudgeonly of observers. These cars were a source of national pride. People would travel from far and wide just to get a look at a Car Program showroom – or even just to meet those test drivers who shook down the cars on the federal test tracks.

But then, about thirty years ago (15-odd years after the car’s introduction to American drivers), the government decided that just blasting all over the roads wasn’t a great use of this invention. So the National Automobile Sales Agency set out to design a car that could be a workhorse for people. Suppose they rolled out something like those late-’80s-and-early-’90s Ford Taurus wagons that used to be all over the place. Functional, not that stylish. They can do a lot of things that you need. However, for the sake of this argument, let’s suppose that these wagons weren’t all that reliable. Or, at least, they worked long enough for all your errands and trips – but after each trip, you had to take it to the shop to get it looked at. This became so commonplace that everyone with one of these wagons just built a trip to their favorite Car Program mechanic into their travel itineraries, and the mechanics all did the same overhaul on every wagon that rolled into their shops. All this got built into the expense of owning an automobile, which climbed far above the initial sticker prices.

For some people, business was great.

And this went on for thirty years.

Then, forty-five years after the first National Automobile Sales Agency hot rods burned up their desert test tracks, an American start-up company unveils…oh, let’s say the Tesla Roadster. They plan to start marketing them as soon as they can, and they get initial support from the Car Agency, but they’re mostly on their own so it’s tough to get going.

But they do. After a couple test drives, they even win a highly publicized performance award. And then they start taking pre-orders.

Meanwhile, another American start-up company is working on prototypes. Their progress is less meteoric than Tesla’s, and they suffer some initial setbacks that make them something of a temporary laughingstock in the automotive enthusiast community. But then they roll out a model that has a couple reeeeeal good test drives. It’s something small, kinda sporty, useful, and most importantly, it comes at a fraction of the price that the Car Agency’s wagons have gotten to. Let’s say it’s a Honda Civic. But this company isn’t done shaking up the automotive community! Immediately after sales start on the Civic, this company announces that it plans to develop…hmmm…I know, the Subaru Outback! It’s comparable in functionality to the National Automobile Sales Agency wagon, but promises higher reliability and low, low prices. What’s more, this company has some additional plans – for a massive thing they call the “pickup truck.”

Now, the National Automobile Sales Agency is at a crossroads. It has big plans and big ideas. It hasn’t spent those thirty years with the wagon idling…but there are issues of cost, and infrastructure. If it had a much more economical way to get access to cars, it could get some sweet road trips going. So it starts thinking about ending production of the venerable, respectable old wagons. Instead, it would just buy some Civics and Outbacks and…”trucks” (when they come along) from this company. With all the extra cash it saved from buying those cars instead of building its own wagons (which, really, are far too expensive to keep on the road at this point and are old enough for antique plates in some states), the Car Program will purchase the infrastructure it needs to set up things like highways and bridges and interstates – things that will really enable Car Program drivers to go far, and go see the sights, and visit just about anywhere in the country. You know – the things that all Americans imagined the Car Program would be doing, before those wagons became so darned expensive and the ordinary citizens stopped paying attention to them.

Because, you see, the National Automobile Sales Agency gets its mandate and direction from Congress. Some Congressmen and -women come from districts that have profited extensively from the Car Program. Members of their districts are the mechanics who service all those wagons, keeping them on the road. Members of their districts are the gas station attendants fueling up those wagons. And members of their districts are the National Automobile Sales Agency employees building and selling those wagons.

(Well, actually, that’s not quite correct. I should have said, “and members of their districts are employees of large automotive corporations that have been subcontracted by the National Automotive Sales Agency to build and sell those wagons under the Agency banner,” but that sounds less appealing and doesn’t work as well for these Congressmen and -women when they are going for political soundbites.)

So, to Congress, the Car Program represents jobs. And, unlike many programs designed to stimulate the economy and create work for citizens, the Car Program is popular. People remember what those hot rods could do, and the mystique of those first test drivers still lingers throughout the country. Despite the promise that exists if the Car Program stops making its own wagons and contracts out for newer cars, Congress punts and punts, trying to keep the wagons on the road.

(Again, that sentence is not quite right. It’s not so much that the Car Program would “stop making its own wagons” and instead buy them from someone else. It’s more like the program would switch subcontractors – to one which offers a more competitive product.)

Eventually, they grudgingly decide that the Car Program does need something new, but instead of telling the Program to do the procurement and design work on their own, they direct the Agency to develop a hot-rod-pickup-truck-sedan-RV-Ferrari-flatbed. (That’s what kind of car design I imagine would come out of a Congressional subcommittee.) And they make sure to apportion parts of this work out to as many states as they can.

But still, some politicians decry this move. They are afraid of all the Taurus wagon jobs that will be lost if the Agency moves to something new. So, despite the facts that the wagons are thirty years old, they are unsustainably expensive to operate, they aren’t taking the Car Program to all the places it could (or should want to) go, and that the Outbacks made by the start-up company have pretty much already obsoleted the hot-rod-pickup-truck-sedan-RV-Ferrari-flatbed (not to mention the older Taurus wagons), these politicians argue that the wagons should be kept on the road artificially. Just to keep the wagon-related jobs going. (For a truly ironic twist, a lot of these politicians are Republican.)

And I sit here and think, “But I want to drive on the highway. I don’t want to pay very much, but I still want to see the Grand Canyon. I want other people to do the same. And I think the Car Program could get back to its roots, and really push the boundaries of what we can do with cars – if it isn’t saddled with the burden of having to re-think all the same problems of wheels and engines. If it just buys perfectly good (and inexpensive!) cars from this start-up company, it will free up resources to develop all those bridges and ferries and tunnels that can take cars places that they’ve never been able to go before. Because the strong suit of the National Automobile Sales Agency isn’t that of being an entrenched bureaucracy full of sinecure positions – it’s of taking the big risks that the private companies never will and thus giving our entire society the big benefits of those long shots.”

In case you haven’t guessed it, I didn’t give the Car Agency the acronym “N. A. S. A.” for nothing.

You see, it’s the day that the Space Shuttle Endeavour – my favorite space shuttle, the only one I got to see launch in person – took flight for the last time. And the headlining articles about the launch were things like this: “Workers Left Rattled By Final Shuttle Launches.” The biggest concerns: Where will all the Shuttle Program jobs go when the Shuttle stops flying?

In that article, one Space Coast resident is actually quoted as calling the retirement of the 30-year-old Shuttle program “insane.”

I sympathize with the human aspect of the story, but at the same time…”insane?” I think not. To me, the most important thing about the space program is the space travel. I think it would be insane to keep the Shuttles flying for much longer. I wasn’t stretching the truth much in my little scenario – in some states, the Space Shuttles could have antique license plates. If they were cars. The Space Shuttle Program is older than I am. Okay, Congress, I grew up steeped in space enthusiasm, got a physics degree, got a Ph.D. in spacecraft engineering, and now I’m ready to push the boundaries of space exploration all the way to – oh, what? You want NASA to keep doing the same thing it was doing before I was born, just to keep certain specific jobs safe? No, thanks. Suddenly the “Space Age” really does look forty years old to me.

What strikes me as really insane is the Congressional shortsightedness that has kept NASA from following through on a coherent vision to replace the Space Shuttles. I had no problem with President Obama’s plans – look at the numbers: SpaceX developed a rocket just as capable as Ares I, but SpaceX managed to leapfrog the Constellation schedule and blow the Constellation program budget out of the water. I can totally understand pointing at the Falcon launch vehicle and Dragon capsule and telling NASA, “Hey, um, how about you just buy some of those?” It just makes good business sense. And it would let NASA spend its valuable time and resources on doing the things that I really would like to see the agency do. The things I know it could be capable of, because it once was. Like go to Mars, or put an way station in deep space, or send robots to sail the seas of Titan, or build self-sustaining habitats so that people can really live and work in space. As if directing NASA to do those things won’t create tons of high-paying jobs to replace or exceed the losses!

But instead, Congress fought tooth and nail for an extra Shuttle launch and ordered up the hot-rod-pickup-truck-sedan-RV-Ferrari-flatbed. And they have no idea where that clunker-to-be is supposed to be going. It’s pretty much set up to fail, and I am completely convinced that the Virgin Galactics, SpaceXs, and other new-space companies of the country (and the world) are going to be light-years ahead NASA in the coming decades unless Congress gets some long-term thinking going in its science and space committees.

These last Space Shuttle launches are bittersweet events – as is the end of any program marked by eye-opening achievements. The last launches were always going to be bittersweet – especially for idealists like me.

But there is a right way to do this. As I said, if there’s some long-term thinking in Congress again – giving NASA lofty missions and appropriate resources, without designing its hardware by committee – we could do this the correct way. The way we used to do it.

You see, Gemini XII was the final flight of the Gemini program. No more Gemini were launched after that. The spacecraft were grounded, retired, and mothballed to museums. But that final flight wasn’t so bittersweet.

Because less than a year after Gemini XII, the first Saturn V rumbled skyward, and less than a year after that, astronauts on board Apollo 7 gazed down at the Earth.

NASA, Politics, Science, Skepticism, Space

To the Moon, Again?

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During a quick lunch break today, I read about H.R. 1641 on Bad Astronomy:

To direct the National Aeronautics and Space Administration to plan to return to the Moon and develop a sustained human presence on the Moon.

(Hilariously, this bill is titled the “REAL Space Act.”)

Like Phil, I think it’s interesting that this act puts a focus on national security issues. I think that’s a stretch – nobody today feels that China getting to the Moon would be as much of a threat as the Soviets getting there in the ’60s. Still, the military and security rationale for having a sustained presence in space is a powerful one. After all, while Armstrong’s first and Cernan’s last words on the Moon put peaceful exploration front and center, Kennedy’s original speech proposing the goal of “landing a man on the Moon and returning him safely to the Earth” contained, just a couple paragraphs previously, this:

Recognizing the head start obtained by the Soviets with their large rocket engines, which gives them many months of leadtime, and recognizing the likelihood that they will exploit this lead for some time to come in still more impressive successes, we nevertheless are required to make new efforts on our own. … But this is not merely a race. Space is open to us now; and our eagerness to share its meaning is not governed by the efforts of others. We go into space because whatever mankind must undertake, free men must fully share.

Got that? Free men must share! The Soviets will exploit space! As Neil deGrasse Tyson paraphrased in a speech, we chose to go to the Moon…in order to kill Commies. Beating the drums makes for a powerful emotional argument, and it’s how our government decides to do a lot of things, from Moon landings to interstate highways.

Personally speaking, I have mixed feelings about this “REAL Space Act.” On the positive side, I think bill represents the way Congress should be treating the space program: giving it lofty goals, and assuring it of funding to support those goals. Oh, what a lovely world that would be!

Still, I’m becoming more and more cynical about Congress and NASA. Congressmembers have fallen into the habit of treating NASA like a big, fat, popular-and-thus-untouchable pork barrel. For instance, in the most recent NASA authorization bill, Congress did not specify where NASA was to go…but they specified exactly what NASA was going to build to go there (a heavy-lift rocket), what technologies NASA was to use on it (solid rocket boosters), and which manufacturer was to supply them (ATK). Oh, that must have been a wonderful bill for ATK, but I have severe doubts as to how much good that approach does for the space program. Instead, I like the approach of giving the space program broad objectives and letting NASA’s engineers make engineering decisions, and this bill seems more amenable to that approach.

However, I’m not sure that going to the Moon in 10 years is a good enough objective. It took us about eight years to go from 15 minutes of human spaceflight experience to landing on the Moon…in the Sixties. With, you know, vacuum tubes and slide rules. My point is: if we really wanted to, I mean really wanted to, we could dust off old blueprints, pull out a big pile of money, and be on the Moon again two or three years from today. What this new bill lacks is something that makes it sound more like we’re going to be doing something that will qualify as a great achievement for the 21st century.

The key might be that “sustained presence.” If the goal is not just to put people on the Moon in 2022, but to have people there and keep going…

That needs to be spelled out. Congress might think it too science-fictiony, but I think words like “asteroid” or “Mars” or “colony” need to get top billing here.

Science, Space

Attack of the Space Junk!

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There is a pretty cool gallery on Gizmodo of various pieces of spacecraft and rocket debris that have fallen to Earth, intact enough to have recognizable shapes.

A fallen rocket stage in Russia

This gallery puts in perspective what we mean when we say things “burn up” in the atmosphere. The friction of re-entry generates enormous heat, usually enough to break up rockets and satellites into tiny, unrecognizable pieces. But every now and then, conditions are just right for bits of spacecraft to make it all the way down to Earth. Some of the pieces are clearly spent rocket parts, which might not have been all the way up in orbit, but a few are most definitely chunks of previously orbiting spacecraft.

This sort of thing highlights one reason why launches all have range safety officers. If there is an unrecoverable problem during a launch, standard procedure is usually to blow up the rocket. The goal of such an action is to break the vehicle up into small pieces that will be much less likely to hit things on the ground.

As usual, the physics here is something that future spacecraft designers might be able to take advantage of: clearly, some spacecraft shapes other than the standard aeroshell capsules can make it to a planet surface. This idea has inspired certain spacecraft research groups to look at developing spacecraft that can get from orbit to the ground by fluttering down benignly.

Note: the problem of orbital debris, shown in the map in that gallery, is related but very different from the issues surrounding re-entering debris.

Concepts, Science, Space

Jovian Electrodynamics

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Jupiter is one of the most useful planets for planning spacecraft trajectories, and it’s home to some of the most interesting science targets in the Solar System. However, it also happens to be one of the most dangerous planets for spacecraft.

Jupiter is so dangerous because of two things: its magnetic field, and the moon Io. You see, Io is extraordinarily volcanically active – the only known extraterrestrial body with active volcanism, in fact – and constantly spurts all sorts of particles out from its interior. The energy of Io’s eruptions gives some of these particles escape velocity, and they end up orbiting Jupiter. Jupiter’s immense magnetic field or solar radiation can then strip electrons off these particles, creating a torus of raging ions around the planet. It’s the same phenomenon as Earth’s Van Allen radiation belts, but without the nuclear explosions and, well, Jovian in scale.

Jovian radiation belts. Sort of. My Jupiter model didn't work, so this picture looks terrible.

Jupiter’s radiation belt kills spacecraft. The Galileo probe, a Jupiter orbiter, eventually died when it crashed into the planet, a protective measure to prevent it from contaminating Europa with Earth life in the event its electronics became too fried to control the spacecraft. (Galileo contrasts quite a bit with the Cassini mission to Saturn, which has been considerably extended from its main science mission!) The next mission to orbit Jupiter, Juno, is encased in a titanium radiation shield. And you can pretty much forget human exploration of Europa.

But it’s not just tempting to send robotic probes to Jupiter – it’s practically a necessity! Any spacecraft headed to the outer Solar System, or trying to do wild orbit maneuvers, needs a lot of delta v (that is, the capability to change velocity – in magnitude, direction, or both). The Ulysses spacecraft needed a bunch of delta v to kick its orbit waaaaaaay up over the sun. And New Horizons needed a ton of delta v to get out to Pluto and beyond. One efficient way to get delta v is to perform a planetary swingby, or flyby, maneuver – and you can get more delta v from a bigger planet. Jupiter is king of the planets and gives space vehicles a huge boost. So, every spacecraft that has ever gone into the outer Solar System has visited Jupiter.

That magnetic field, though. Jupiter has a magnetic moment 18,000 times as large as the Earth’s. That sort of magnetic field is useful, if a spacecraft has the hardware to take advantage of it. For instance, an electrodynamic tether: a long conductive filament stretching from the spacecraft, along which the spacecraft runs a current. (Currents through the rarefied plasma filling the Jovian orbit environment complete the circuit.) The spacecraft will then experience a force proportional to the cross product of the current along the tether and the local magnetic field. If you don’t like vector math, don’t worry – just remember that the force is perpendicular to both the tether and the planet’s magnetic field near the spacecraft (which, near the planet’s equator, will run approximately parallel to the planet’s spin axis). In Earth orbit, there have been several missions testing tether physics, with applications including both electrodynamic propulsion and harvesting power from the Earth’s magnetic field. Around Jupiter, these methods will be even more powerful.

If a spacecraft is in circular orbit around Jupiter and orients a tether parallel to its direction of travel, then the force will be either directly toward or directly away from the planet’s center. This means that the spacecraft can, by running a current through a tether, generate a force that has the effect of either enhancing or weakening gravity. So a robotic probe performing a Jupiter flyby could get a much bigger gravity-assist boost with a little help from a current-carrying tether. Or, if the current is high enough, the net force could repel the spacecraft from Jupiter, changing the direction of the delta v it picks up in the flyby. The capability for spacecraft to perform that kind of maneuver could open up more launch windows for outer Solar System missions.

Another idea is to use electrodynamic tether propulsion to keep a Jupiter orbiter out of the worst parts of the radiation belt, so that it can get lots of data on the Galilean moons. If the probe has a slightly inclined orbit, then it could vary the current in its tether over the course of each orbit so that the spacecraft pushes its semimajor axis in and out each period. With the right parameters, this non-Keplerian spacecraft trajectory would skirt the ring of hard radiation around Io’s orbital radius.

A trajectory that skates around the radiation belt

Perhaps the spacecraft has some leeway into how far into the radiation belt it can venture – or its orbit is just bigger than the “danger zone.” Then, it could follow a Keplerian orbit (affected only by gravity) some of the time and use the passage of the tether through Jupiter’s immense magnetic field to generate electricity. If engineers can balance the numbers, then such an exotic orbit might come out power-neutral over the course of each orbital period, giving spacecraft a free, and safe, way to explore Jupiter’s Galilean moons for a very long time.

Speaking of power harvesting: Jupiter is far enough from the Sun that spacecraft around there can’t really get all the power they need from solar panels. Dragging a conductive tether around and letting the planet’s magnetosphere drive charges along the length of the filament would be one way to overcome that challenge.

These are kinds of technologies that we can develop in Earth orbit and deploy in the outer Solar System, to take advantages of the resources out there and allow us to learn more about the things in our backyard. After all, the more we understand about the different regimes of our own Solar System, the more we understand about our origins – and about the possibilities that exist in planetary systems around other stars.

Concepts, Gadgets, Space

REAL Space Legos!

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So, MAKE Magazine has this on their current cover:

That’s a Lego Mindstorms NXT computer and other Lego pieces on a spacecraft. “Cool!” my labmate and I thought upon seeing this. “Satellites made out of Legos!”

Well, it turns out that the article says this is a picture of a functional satellite prototype made out of Legos by a group at NASA’s Ames Research Center. (The same group that recently launched a spacecraft that used a cell phone for its computer system!) But, you know…why not? Why not make a satellite out of Legos? I think this would be a great idea!

What would it take?

The physical structure of a Lego-brick satellite would have to withstand the rigors of a launch into space. This involves accelerating the satellite and subjecting it to heating from friction as the rocket climbs, among other things. Space Mission Analysis and Design, Third Edition, gives the following “typical values” for acceleration and thermal requirements of satellites in a launch vehicle:

  • Acceleration: 5-7 g, but up to 4,000 g shocks during stage separation and other events.
  • Temperature: 10-35°C (but the inner wall of a Delta II fairing could get up to ~50°C).

The acceleration requirements, though that shock value sounds drastic, may not be too much of a problem. G-hardening is potentially easily accomplished by potting components in epoxy.  Modern cell phones, for instance, are rated to several thousand g‘s so that they work even after you drop them. A good epoxy applied to all the joints in the Lego spacecraft structure, and probably around the whole structure after it’s completed for good measure, could go a long way toward preventing this from happening during launch!

I’m more worried about the thermal requirements. Lego bricks are made out of acrylonitrile butadiene styrene, which seems like it starts getting deformed due to heat at about 65°C. That 50°C Delta II fairing seems a bit close for comfort! Plus, the temperature of some Lego blocks sitting in direct sunlight in space could climb above this value very rapidly – and lots of transitions between daylight and shadow would cause the parts to expand and contract thermally, working the pieces apart if they aren’t well-secured with epoxy. However, the Lego satellite could be wrapped in something like aerogel or MLI blankets to mitigate the thermal challenges. Somewhat.

Another challenge is survivability of the computer system in the space radiation environment. With no atmosphere to absorb radiation, a cosmic ray could hit the spacecraft and trigger a single-event upset, or “bit flip,” that switches the value of a bit from 1 to 0 or vice-versa. This kind of thing happens to spacecraft computers all the time and corrupts data, so spacecraft computers engage in a lot of error-checking. But the same cosmic rays can also burn out a bit, so that the computer can never read its value again – or even burn out a trace in an integrated circuit so that the circuit fails! That sort of thing would definitely be a problem for a Lego spacecraft, and would shorten the life of the computer substantially unless we did some radiation hardening of the NXT. A simple way to harden it would be to encase it in some metal, but that adds mass, which is always at a premium on spacecraft. However, another strategy is to simply accept that the spacecraft will have a short life in orbit!

…Because, after all, what would be the purpose of launching a satellite made of Legos? It would be to show that commercially available materials are sufficient for at least some space applications, without the millions of dollars of investment in robustness and fault tolerance that the spacecraft industry generally demands. If the satellite’s mission can be accomplished in a few days and the lifetime of the craft is a week, then why should all of its components be certified for years of operation in orbit? Perhaps we could, instead, come up with much cheaper – or much riskier – satellite designs. We could try out new materials, new components, and new mechanisms without designing them never to fail. Instead, we accept a few failures as learning experiences, and move ahead with the designs that work.

Legos are, at least, a fun place to start. Perhaps most importantly, they are easy to get into the classroom, so that students can think about building the structure, thermal, power, electrical, and payload systems into a functional satellite – and can re-arrange or re-format those systems at will. But hey – when they’re done, why not launch?!

NASA, Science, Space

Sailing into Light

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This week, the NanoSail-D mission successfully deployed from FASTSAT. This is, apparently, the first time a nanosatellite has ejected from a microsatellite.

(In spacecraft lingo, engineers grabbed the term “microsatellite” to just mean “a small satellite,” where “small” was in comparison to the spacecraft with masses of thousands of kilograms. But they kept the relationship between the metric prefixes. So a “microsatellite” is about 100 kg or less, and a “nanosatellite” is about 10 kg or less. This is unfortunate for, say, my research group, because our proposed millimeter- or micron- scale spacecraft would have to be named something inconvenient to say, like “yoctosatellites.” Anyway.)

I think NanoSail-D is exciting for two reasons. First, it’s only the second solar sail mission to not explode on launch, after JAXA’s ICAROS mission. (The Planetary Society tried to launch a solar sail five years ago, but the converted ICBM launch vehicle malfunctioned.) Solar sails are a propulsion system that could allow spacecraft to move around the Solar System without expending propellant, so they would be a great technology for getting from planet to planet efficiently. The downside is that solar sailing takes a long time, but fortunately, robots can have long lives and a lot of patience. More solar sails may mean more robotic missions to planets, asteroids, and moons all over the place, which is a good thing for science!

The other reason why NanoSail-D is cool is this microsatellite-deploying-a-nanosatellite idea. Microsatellites are small and low-cost enough to have a pretty rapid development cycle, and spacecraft engineers are less averse to trying out riskier, newer technologies on microsatellites. FASTSAT is a great example: it’s a technology demonstrator mission, a spacecraft devoted entirely to trying out new things. Nanosatellites can be even faster and cheaper to build, so much so that it’s pretty common for universities to build CubeSat projects and you can buy components to build a fully-functional CubeSat off the internet for $100,000 or less.

So with FASTSAT and NanoSail-D, we have a relatively cheap spacecraft with a rapid development cycle that includes cool new technologies – and it launches an even cheaper spacecraft with even riskier technologies, including one that could allow interplanetary trajectories.

These are the ingredients we need to get probes all over the Solar System, and these are the design philosophies that push the envelope of spacecraft engineering.

NASA, Space

Space Access Gap: Closed!

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SpaceX’s second successful Falcon 9 launch has just inserted the Dragon capsule into Earth orbit!

First Falcon 9 launch (SpaceX)

The Dragon vehicle will perform a series of check-outs over the next few orbits before re-entering the Earth’s atmosphere. If all goes well, then this is a major success for SpaceX and NASA’s COTS program – which seeks to contract International Space Station supply missions to private companies after the Space Shuttle retires, so that ISS has more resupply mechanisms than the Russian Progress vehicle and European ATV. SpaceX wants to human-rate the capsule, as well, to provide astronaut transportation to orbit and even space tourism!

Today's launch (NASA)

Again, if all goes well, this mission ought to be vindication for President Obama’s vision for NASA: use commercial providers to get into Earth orbit, and then let NASA focus on the real envelope-pushing exploration. If the Falcon 9 gets to orbit, and the Dragon could take cargo or people up, then why don’t we just buy those for a fraction of the cost of the Ares 1/Orion system? Especially since that system would take many more years of development to become available to NASA. The Falcon 9 and Dragon will be ready much, much sooner!

Best of luck to the SpaceX team. And may the Congresspeople holding NASA’s purse-strings get their heads out of their pork barrels.

Update 1600 8 Dec 10: At the post-flight press conference, Elon Musk and Gwynne Shotwell of SpaceX gave an overview of the mission and a rosy assessment of its success. Apparently, the Falcon 9 second stage reached a very health apogee – well above the ISS orbit – the Dragon performed well enough in space to maintain a good lock on the TDRSS relay satellite, and it successfully splashed down within 10 km of its target and within a minute of its projected landing time. Musk stated a couple times that his “mind was blown” and pointed out that, had there been people on the Dragon spacecraft, they would have had “a very nice ride.” He thinks that all (“all”) Dragon needs to be human-rated are seats and an escape system, though he did admit that launch-escape system testing is both crucial and very hard. Apparently NASA officials told SpaceX that, if this flight went well, they would consider allowing an ISS rendezvous and docking on the next Dragon flight, so that may be a possibility for next year. Another Musk gem, on the politics of SpaceX’s activities: “any politician who wants to increase the deficit and reduce American access to space, go ahead and cut [the NASA Commercial Crew program].”