Orbital launch vehicles are strange creatures. They are
thuggish brutes, rising, roaring upward into the empty sky on an ecstasy of fire.
They are delicate, their skin nearly thin as paper, every possible gram of
metal whittled and etched away while retaining the faintest positive margin of
strength. They are intelligent, able to pinpoint a plane, an altitude, and a
speed, an imaginary keyhole past the atmosphere, and drive toward it with
ferocious precision. They are dumb, carrying many tons of oxygen blasting
through an oxygen-rich atmosphere, too busy to make use of what’s around them.
They are expensive, a collaboration of the finest machinations of the
stubbornest minds brought to bore on the problems of extreme performance in the
last century. They are cheap, cast aside like garbage after doing their work to
the bottom of the ocean or the depths of space.
By far the oddest quality of these rockets is their
expendability. It’s hard to imagine any other machine of such careful
engineering being jettisoned in such a careless way. But the carelessness is a
clear product of the physics of spaceflight. It’s hard enough to get from the
surface of the Earth to the lowest footholds of space, the argument goes. Why
make a hard problem even more hopeless by trying to turn back to save what you’ve
created? So we make sacrificial virgins of our launch vehicles, consigning them
to a funeral pyre in the upper atmosphere after sending their payloads on their
way.
If we’re serious about establishing an enduring, robust, human presence in the cosmos beyond the
lushness of Earth, we need to have a better attitude toward rockets that have
made the journey. They need to come back. Their tanks need to be refilled. They
need to fly again. The economics of reusability are difficult to get right. The
Space Shuttle certainly didn’t get them right. It was never cheaper to buy a
launch on the shuttle (assuming NASA would let you) than it would have been to
launch the same payload on an expendable rocket, despite the fact that most of
the hardware that launched on each shuttle flight could be used again. But the economics
of reusable rockets are the only method of getting stuff into orbit with any
hope of getting it right. After a long hiatus full of scholarship but mostly
devoid of action, we’re finally, as a civilization, starting to work on getting
this right again, and SpaceX’s stunning return of the first stage of a Falcon 9
v 1.2 last night is a major step along this path.
There’s an eerie, entropy-defying quality to the videos,
like somehow the arrow of time got flipped around. In hindsight it all looks so
perfect that it’s difficult to remember how uncertain this success was. SpaceX
built to this moment incrementally. They learned hard lessons about
aerodynamics, retropropulsion, and controls along the way. They came
agonizingly close to success only to see the results go up in flames. Last
night the mountains of analysis, design, work, and sweat paid off with a used
rocket standing on the landing zone pad, huffing and puffing from a 10 minute
sprint, exhausted, toasted, but alive.
This stage will probably never fly again. The opportunity to
pick apart a machine that’s harrowed the underworld of hypersonic flight into
space and returned is almost as rare as opportunities come in the engineering
world, and I expect that the people of SpaceX will inspect and document every
weld, bolt, and valve before putting the stage on display at Hawthorne or
McGregor. The first rocket to make it back will be a well-deserved trophy. The
burden of truly proving the concept will fall to her younger sisters.
Space travel is very expensive, even after 58 years of
on-again, off-again efforts to advance the state of the art and make it easier
to get there. It’s possible to meaningfully reduce the cost of getting to space
by making launch vehicles simpler and cheaper and being satisfied with a single
launch per rocket. But consider the cost of the propellants that took the 11
Orbcomn satellites carried by last night’s launch to their new home compared to
the cost of the vehicle. My naively conservative analysis suggests that SpaceX
spent less than $400,000 on liquid oxygen and rocket-grade kerosene, while the
list price for a Falcon 9 launch is over $60 million. I don’t believe it’s
possible to build a truthful economic case that spaceflight will ever be
affordable enough to enable things like commonplace research and manufacturing
in microgravity, asteroid mining, and the human settlement of the solar system
as long as orbital launch vehicles are one-time use. I don’t think it’s
possible to make a machine that can get from the surface of the Earth into
orbit cheaply enough. Even if reusable launch vehicles can’t do better than
operate at 10 times the cost of the propellant they consume, that’s a factor of
15 improvement over where we are now. That’s where the (relatively) low-hanging
fruit lies.
This matters because whether or not spaceflight becomes
something that most people on Earth can take part in directly affects whether
the future of our civilization is an optimistic one or a pessimistic one. The
settlement of Mars and a widespread human presence throughout the solar system
isn’t a flight of fancy. This is a practical, possible reality that’s the only
viable alternative to a long-term future where we scramble to find ways to make
slightly better use of the limits of Earth, confined to a single lonely mote of
dust in the universe. The choice, in the long run, is between growth and
discovery, and stagnation and decay. I’m assuming, if you’re not a member of
the voluntary human extinction movement, that you’d prefer the former.
What SpaceX did last night is a bold step toward the
optimistic future for humanity and Earth. Much more work needs to be done, by
many people besides those working at Hawthorne, McGregor, and Cape Canaveral.
SpaceX cannot by itself make humanity a multi-planet species. The work going on
at my employer, Virgin Galactic, at Blue Origin, and at all the other small entrepreneurial
space companies are an essential part of this effort. In no way does SpaceX’s
success in their landing last night detract from how remarkable and wonderful
Blue Origin’s successful flight was earlier this year of their New Shepard vehicle to the edge of space
and back. Anyone who suggests otherwise would do well to tone down their Elon
fever and embrace the effort to make spaceflight more affordable throughout the
industry. It looks like the more established figures of the industry, from NASA
to Boeing to United Launch Alliance, are starting to get on board with
reusability, too. With a lot of work and some luck, this will be the start of
the first real revolution in how things get to space since Sputnik.
Each night my wife and I read to our son the readings of the
day from the Catholic lectionary. Last night’s readings were oddly appropriate
given the historic events earlier that evening. The Old Testament piece was
from the Song of Songs, and it’s a favorite of mine, one of the readings my
wife and I had read at our wedding. It’s a poem that touches on love and hope,
eros and thanksgiving. In part, it reads as follows:
“Arise, my beloved, my
dove, my beautiful one,
and come!
“For see, the winter
is past,
the rains are over and
gone.
The flowers appear on
the earth,
the time of pruning
the vines has come,
and the song of the
dove is heard in our land.
The fig tree puts
forth its figs,
and the vines, in
bloom, give forth fragrance.
Arise, my beloved, my
beautiful one,
and come!"
Most of the universe is full of death. Not in the sense that
it’s actually evil, but in the sense that it’s immersed in a dark night of inertness.
Life, like light, fills a void, and precious little of the universe we live in
has any of the light of life within it. The machines that sever our ties to
Earth enable us, the intelligent part of the biosphere that can think of the
future, plan for it, and make it better, to bring at least some of what’s out there
into the bloom of life. Only if we rise from the Earth can the winter of death
in our part of the cosmos end. I think this is worth doing.
So I celebrate what SpaceX has done to move us along this
path. I’m glad I can play some part in this effort, too. Seeing what wild
lovely celebration engulfed the men and women who made this a reality in
Hawthorne, I can’t help but smile for what happened last night, and for what
lies in store in the years to come.
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