Archive for the ‘Space exploration’ category

The beginning of the end for NASA?

15 September 2011
Categories: Space exploration

This week NASA announced its Next Big Thing: the “Space Launch System,” a heavy-lift vehicle that will provide the basis for a new generation of crewed deep-space missions, and renew U.S. launch capability in the post-Shuttle era.

Cool. I’m excited. In the space program, it’s okay to equate New with Good. Anything with the potential to expand our knowledge of and presence in the solar system (and maybe even reduce our dependence on our home planet) is worthwhile. And then there’s the ooh-aah factor of the numbers: Three to five times the payload capacity of Space Shuttle! More powerful than the venerable Saturn V! Our biggest rocket ever!

But I’m extremely skeptical about this announcement, and about NASA’s plans for the future—so much so that I have the eerie sense that with this new program NASA has signed its own death warrant.

NASA spent five years fiddling around with the Constellation program before it was cancelled, at untold cost for that abortive development. SLS will require another five years, minimum, before the first test launch will fly—and its first crewed mission isn’t expected to occur until 2025.

Why so long? The answer, of course, is money. We live in an era where the U.S. defense budget is over half a trillion dollars annually, while the education budget is less than one-seventh of that. Congress has flatlined the NASA budget for the foreseeable future. Given those realities, one has to wonder whether NASA couldn’t find a more cost-effective way to spark the public interest, rather than the piecemeal construction of a massive new launch system for the next two decades or more.

Meanwhile, from a hardware standpoint, the SLS plan is far from perfect. NASA has chosen the Rocketdyne RS-25D engine for the main stage, an engine better known as the SSME (Space Shuttle Main Engine). The RS-25 is widely reputed to be the most complicated engine ever built. NASA chose this over the newer RS-68—an engine that is the result of lessons learned from real-world experience with SSME, an engine that has 80% fewer parts, costs less to build, uses the same propellants, and has a reasonable thrust-to-weight ratio—because of the necessity of modifying RS-68 to make it “human-rated.”

The idea is this: NASA has a stockpile of tested RS-25D engines of known quality and reliability—most (if not all) have already been used for Shuttle flights. The cost to take these engines out of mothballs and bolt them to a new airframe is (relatively) minuscule. This defers the cost of main engine development and production until later in the project, which (in the short term) would seem to NASA to be fiscally prudent. Then, the RS-25 would be modified and simplified for expendable use, and production would resume. As the production line comes up to speed, and SLS launches come more frequently, the unit cost of new engines would decrease.

Seems to me I’ve heard this argument before—with Space Shuttle. The high cost of early launches was expected, as the spaceplane reached operational status and made flights with clockwork regularity, to drop precipitously to a downright economical level. Yet Shuttle’s “cheap access to space” never came to be. Hypothetical economies of scale don’t seem to come to fruition very often in the spaceflight game.

I suspect that simplifying the RS-25 to make an expendable version, the RS-25E, requires no less of a development and testing cycle than would be entailed in modifying the existing RS-68 for crewed launches. At the same time, RS-68 already has an existing production line and expectation of continuing use, since it is the main engine of the Delta IV rocket. So why start up a completely separate production line, and employ all those rocket engine builders, for a system that, as currently planned, will need at most five engines per year?

The biggest problem comes down to this: the old adage “time is money.” The longer it takes to get SLS flying, the longer the gap between flights, the more expensive the total program becomes. How many people will be employed, day after day, to make this system happen? What will the ongoing cost be, in salaries and benefits, when it only flies once per year? More to the point: Is this a space program, or a jobs program?

We have the hardware. Assuming the short-term frugality (and long-term myopia) of using RS-25 engines, and with the flight-proven hardware of the Shuttle’s ET as tankage, why must it take six years to get one off the ground? Wernher von Braun and his gang could have whipped together a flight-ready model in much less time—two years perhaps, and four years tops. Just look at what they were able to do with the Saturn I/IB.

If this announcement had come in 1972, in lieu of the Space Shuttle, I’d be excited. Back then NASA might have had the budget and the public impetus—and the gumption—to make it happen, and something exciting probably would have come from it. We might even have walked on Mars by now. But to make this announcement now, with NASA an agency both so bureaucratic and risk-averse as to be vapour-locked, with Congress only allotting it a shoestring budget, and with no clear notion of where SLS might go (and who will pay for it to get there), it seems like too little, too late.

So long, farewell, we’ll miss you, and… good riddance?

22 July 2011
Categories: Space exploration

This week Atlantis made the final landing of the thirty-year-long Space Shuttle program. It was a momentous day; thousands of people flocked to the Kennedy and Johnson Space Centers to witness the end of an era. Fully aware of the historic nature of the event, everyone involved shared some finely crafted words, including these from NASA commentator Rob Navias as the Shuttle rolled out on Runway 15:

“Having fired the imagination of a generation, a ship like no other, its place in history secured, the Space Shuttle pulls into port for the last time, its voyage at an end.”

When Commander Chris Ferguson spoke an uncharacteristically wordy version of the standard end-of-mission call “WHEELS STOP,” I—like many Americans—burst into tears. The finality of the moment, combined with the uncertainty of the future of American human spaceflight, was deeply emotional. Space Shuttle has been, as a friend put it so aptly, “our generation’s technological icon,” pervading everything to do with space for three-quarters of my life—nine-tenths if we go back to the 1972 announcement by President Nixon that got the ball rolling.

I’m proud of what the United States has accomplished in spaceflight, and I sincerely hope that this country continues in a leadership role for future spaceflight endeavours. But in the back of my mind, even as my tears dried, I felt a deeper regret—not for Thursday’s closure, but for what might have been.

Someday, if humanity has sufficient luck and foresight, we’ll find a way to live beyond this planet before we make it so uninhabitable that we kill ourselves off. If that happens—and I’m not confident it will, but that’s a different subject—I suspect that those humans living on such far-flung worlds as Mars and Titan and (apologies to A. C. Clarke) Europa and perhaps even beyond this solar system will look back on their distant past, the early days of human spaceflight, and remember the Shuttle and say, “What the heck were they thinking?”

Because, putting aside all tributes to an amazing piece of technology and the hard work of thousands that made it possible, it must be said: Space Shuttle was, from its inception through its final flight, a boondoggle.

It was born on a promise of efficient and economical access to space, a promise it was never capable of delivering. Turnaround time, theoretically touted as less than two weeks, rarely fell below two months, and usually ran to four or five.

It was, as I once heard it called, “a camel—a horse designed by committee.” Compromises and political necessities, fettered only by engineering realities, held sway over the design process. The military imposed its own set of rules, even though the final design had a cargo bay too small to contain the tour-bus-sized spy satellites the DOD was already building. By the time it flew, Space Shuttle was a delivery vehicle that satisfied the needs of none of its intended customers.

It was a transport without a destination. The original proposal was for a spaceplane and a space station for it to go to, yet for the first seventeen years of Space Shuttle operation there was no International Space Station in orbit. (For five years prior, the Soviet/Russian Mir acted as an occasional stand-in, mainly as an excuse to prop up a faltering Russian space industry.)

It was dangerous to fly, even by “spaceflight is inherently dangerous” standards. No launch escape system was included, despite having been standard on Mercury, Gemini, and Apollo—and today’s Soyuz vehicles too. And, as the crew of Columbia fatefully discovered, strapping life-supporting hardware to the side (rather than the nose) of any launch vehicle, all of which tend to shed debris during launch, is a Very Bad Idea.

I could go on, but the point is this: if the United States had chosen instead to continue with stripped-down, Earth-orbit-capable Apollo-style spacecraft; stuck with existing launch vehicles and worked to improve and simplify them, maintaining a human-rated launch capability using expendable rockets; and put its effort into constructing a space station that could serve as both science laboratory and orbital way-station to deep space; then where would we be today?

Figure a few years to get started; the first module might not have flown until 1975 or so (unless Skylab became module 1, in which case 1973; but no matter). Get the Russians on board, as a more substantial (and genuine) act of détente than Apollo–Soyuz, and figure construction would take about as long as ISS—fourteen years.

That puts completion at 1989. More than twenty years ago, to get us to the point where we are now. And yet ahead of where we are now as well, because we still would have had usable flight hardware, like the Russians do with Soyuz. We would not have been staring down a gauntlet of untold years before private enterprise might fill the launch gap, as we are staring now. NASA estimates it will be five years or so until human spaceflight from American shores resumes; I’ll wager it will be at least ten years, perhaps as many as fifteen—at which point, ISS will be nearing retirement.

Where will America go next? There is no clear answer to that question. U.S. space policy is in “disarray,” to put it mildly. Massive budget cuts are coming to NASA. Robotic exploration, for all its scientific advancement, doesn’t spark the public interest: the arrival of the Dawn spacecraft at asteroid Vesta last week was met by a yawning apathy—even from me, and I have a distinct, specific interest in that particular mission.

That’s what makes me truly melancholy today. Not the end of the Space Shuttle program—it had a good run, and a lot of good things came out of it. Rather, the broad chasm standing before us, one lacking exploration to spark the imagination, challenges to inspire the next generation of scientists and engineers. As the classic IMAX film put it, “The Dream Is Alive.” But for how long?

Moondust: In Search of the Men Who Fell to Earth by Andrew Smith

20 December 2010

Apollo 11 happened in my lifetime, but I’m much too young to remember it.

Andrew Smith remembers it: he was a lad of eight, and begins his brilliant book Moondust with his recollection of a warm summer day, riding his bike with a friend through their Northern California subdivision, arriving home in time to hear the last minutes of the descent, and sitting in his living room a few hours later to hear Neil Armstrong utter those famous words.

I was not quite six months old when the Eagle landed, so I remember nothing of it. My family was on a camping trip, and during the Moonwalk, the One Small Step, I was fast asleep in a big canvas tent. My parents, only vaguely aware that the world’s attentions were so acutely focused on this event, stood half-interested along with a handful of other people around a small, black-and-white portable television owned by the folks in the next campsite over. The reception was awful—and of course the images from the Moon were grey and ghostly at best—so I think their experience of the event was rather underwhelming.

One of my earliest memories of any kind is of Apollo, although in researching its specifics now I find that my recollection may be entirely flawed. In my mind, as a not-yet-four-year-old I was awakened in what seemed like the middle of the night by my grandfather and hauled blearily down to the basement to watch as Cernan and Schmitt climbed aboard the Apollo 17 Lunar Module Challenger and the last men launched from the Moon. The tricolor debris of liftoff—the red-green-blue scans of the lunar rover camera being sequential rather than simultaneous—still sticks in my mind as one of the archetypal images of the entire program.

Except that in the time zone where I was, the lunar liftoff took place around dinnertime. Perhaps the late-night rousting I recall was of the mission-commencing Saturn V launch from Florida instead, which took place well after my bedtime. If that’s the case, I have to admit to remembering it not at all.

At any rate I was young enough not to notice the hiatus, the huge gear-grinding downshift, when Apollo ended and the only things happening in American crewed spaceflight for more than eight years were a trio of long(ish)-duration Earth-orbital missions aboard a converted Saturn V third stage, and the brief effort in détente known as Apollo–Soyuz. My media input was mainly from books, and in those books—among them NASA’s Apollo Expeditions to the Moon, Ruth Sonneborn’s Question and Answer Book of Space, and of course Carl Sagan’s masterpiece Cosmos—human spaceflight continued its merry ascent toward the stars, unfettered by political machinations and budget considerations.

Since then, along with biographies on Neil Armstrong, Michael Collins, Gene Cernan, Gene Kranz, Deke Slayton and others, I have read dozens of books on the Space Race, Apollo, the Moon landings. Some are sublime, like Andrew Chaikin’s A Man on the Moon; some are fairly routine, cut-and-dried, and uninspired; some, like Tom Kelly’s Moon Lander and Roger Bilstein’s Stages to Saturn, are rife with technical detail. Some are just going through the motions, praying to get all their facts correct (and, often as not, failing).

But few, if any, pose a question both simple to ask and complicated to ponder: What did Apollo mean? And for that matter, what does it mean today, decades later?

Andrew Smith chooses to ask those questions. By chance he found himself in proximity to Charlie Duke and his wife as they learned of the death of Duke’s fellow Moonwalker, Pete Conrad. Duke’s shattered comment to Smith: “Now there’s only nine of us.”

This sets Smith on a journey to meet all the surviving Moonwalkers and get their impressions of their time on that celestial body. But not to answer the prosaic and frequently asked “What was it like to walk on the Moon?” He delves more into the question of “What was it like to return to Earth after having walked on the Moon?” He focuses on the aftermath of each mission, the paths (some clear-cut and successful, some desultory and haphazard) each astronaut took upon splashdown.

Smith’s story of the Space Race and its aftermath is delightfully candid and uniquely personal, and is not only a fun read but also an important contribution to the history. I would even go so far as to say that, if after reading the best book on the Space Race bar none—Chaikin’s A Man on the Moon—readers find themselves wanting more, they could do far worse than to turn to this book for further perspective.

Andrew Smith comes to some interesting conclusions about what it all “meant,” but it does him no justice to attempt to condense them down to a few paragraphs. Suffice it to say that Moondust takes us on a personal voyage of discovery, clears away the veils of mythology surrounding Apollo, and brings the Moon home to all of us on Earth.

That said, one glaring point Smith makes in conclusion hit home to me.

He discusses the real reason that Lunar Orbit Rendezvous, an outsider (if not radical) idea, was chosen over the Earth Orbit Rendezvous favoured by NASA’s top engineers: time. LOR stood a better chance of getting the job done before Kennedy’s arbitrary deadline.  But EOR’s incremental approach was the better way:

Earth Orbit Rendezvous would have taken longer, but would have bequeathed a waypoint in space, prepaid for and pointed out toward the stars. It could have been scaled up or down and adapted to a range of purposes with relatively little bother. It would have involved developing technologies and skills that would endure, so that when the political imperatives that drove Kennedy had gone and the lunar landings ceased, an orbital base camp would have been left behind. The Sixties-end deadline had necessitated a built-in obsolescence that was the quintessence of its time.

For all the Space Race history I’ve read, I cannot recall having seen this idea expressed so flatly, so concisely, if at all:

Jack’s Apollo program killed “manned” Deep-Space exploration, stone dead, for at least the next four decades and probably many more.

It’s not a popular notion, that the man we think of as having sent us to the Moon ruined spaceflight for us. Unfortunately, it’s true. For the past thirty years we’ve been launching the Shuttle back and forth to low Earth orbit—and as Smith suggests, the difference between that and a voyage to Deep Space is akin to the difference between climbing a hill and actually flying. The International Space Station, for all its size and arguable science potential, goes nowhere. While the Russians are still flying a 1960s spacecraft aboard a 1950s rocket (both substantially upgraded and modernized, of course), not one bit of our moonshot hardware carried over into the Shuttle era. Apollo really was disposable.

Most people don’t realize the cold hard fact that today, in 2010, the human race lacks the technology to return to the moon. What we did forty years ago, we can no longer do. When I tell people that, they’re almost always shocked. We’ve lived so long with that old saw—“We can put a man on the moon, so why can’t we do x?”—that it doesn’t occur to us that its premise is false. We can’t put a man on the moon.

Why? Because JFK wanted to beat the Russians at something, and somebody said we could beat them to the Moon, and so we did. But we did so at the expense of a sustainable space program.

In 2010, the year A. C. Clarke used for our second crewed voyage to Jupiter, forty years after Alan Shepard played golf on the Moon, how sad it is to be twiddling our thumbs in low Earth orbit and heading into yet another gap in U.S. crewed spaceflight capability. Thanks for nothing, Jack.