sapiens to homo stellae.
Why do people
dream of achieving Everest's summit? What makes the unknown
so attractive? Given all the problems we face, why do we invent
new ones to solve? Human nature: our babies are the ultimate
adventurers. They explore, they imagine, they poke and prod
at everything they can see and reach. And as soon as we could
see our neighboring planets, we too wished to reach them.
is the cradle of the mind, but we cannot live forever in a
(Konstantin E. Tsiolkovsky [1857-1935],
father of astronautics. Kaluga, 1911, from a letter.)
on this page courtesy of NASA and the University of Washington.
recycle. Oddly enough, this mantra of environmental sustainability
also sums up the requirements for economically viable spaceflight:
reduce weight, re-use the rockets, vehicles, and tools, and recycle
the components. Innovations in materials science coupled with the
march of Moore's Law faster, smaller, cheaper, more interconnected
microprocessors will unlock the doors of space for scientists,
businesspeople, tourists, even students and their teachers. Especially
if the technological innovations can be combined with design enabling
"continuous intact abort capability" that is, the ability to
abort a flight safely at any point during the flight, and return home.
Then a safe path to space will truly be accessible to all.
Our first tours of Mars
will be on-line. A sash of satellites in orbit above Mars will relay
commands to sensor stations and robots on the Red Planet, and transmit
data and visuals back to Earth. The first node of a system-wide
"Interplanetary Internet," this communications network will allow
scientistis to explore via telepresence and teleoperation
and allow the rest of us to kibbitz. Based on the communications
protocols of our terrestrial Internet, the architecture will more
closely resemble a "network of Internets," in order to handle the
varying transmission times between moving planets. Initially, designers
will focus on security to prevent the "hacking" of Mars.
But in two decades, a popular coffeebreak pastime may well be pitting
one's reflexes against interplanetary lag times to control small
roving robots on Mars or the Moon.
By 2015, an entire silicon
ecology of robots could act as on-line tour guides on Olympus Mons,
or through Valles Marineris. The prototypes are already there: Pathfinder
and its mobile unit, Sojourner, as well as the Mars Global Surveyor.
But NASA has even more robots in the works, ready for launch over
the next decade. In 2003 NASA will launch twins: the identical Athena
geological rovers, building on the success of Sojourner. Space scientists
are also borrowing from nature to design autonomous, insect-like
robots that could be deployed in large numbers, and nanoscale information
sensors that could be dusted across the landscape.
Rovers, however, can
only rove so far. The subsequent generation of Mars explorers could
be airborne, and inflatable. NASA and students at MIT
are designing robotic airplanes and gliders to skim through the
valleys and canyons of Mars, and ride thermals over its mountains.
Hot air balloons, which would rise in the relative warmth of day
to land again at night, are also on the drawing boards. All these
designs rely on inflatable structures. The Jet Propulsion Laboratory's
"Gossamer Spacecraft Initiative" explores these uses as well as
designs for lightweight, inflatable telescopes, "ballutes" (balloon
parachutes) and light, inflatable heat shields.
NASA cancelled the X-33
spaceplane prototyping but continues its search for transportation
systems to carry people and equipment safely and reliably to orbit
as are over twenty private engineering teams. (see sidebar)
While spaceplanes like the Pan Am spaceplane seen in "2001" represent
one design path, we may one day simply take an elevator to orbit.
Tsiolkovsky and colleagues in Russia suggested "space towers" to
lift passengers and cargos out of Earth's gravity well, and Arthur
C. Clarke portrayed the idea in his novel, The Fountains of Paradise.
New high-tensile strength, self-healing composites and materials
will not only make our spaceplanes safer, but could make the idea
of a floating tether a cable dangling down, and stretching
out, from a "buoy" in orbit feasible. The lower docking station
would be suborbital, allowing simpler, lower-cost spaceplanes to
ferry people to the "elevator's" lowest point. Passengers would
then ride for several hours in large, comfortable gondolas up the
cable to a space station at mid-point. Interplanetary cargo would
continue up the cable to the high end, where it would be flung off
the cable at speeds exceeding escape velocity.
With weight one of the
biggest constraints in launch costs, designers are also using advanced
materials such as highly heat-resistant, featherweight carbon mesh
to make inflatable interplanetary and interstellar spacecraft, such
as solar sailers. Solar sailers will rely on the faint push of the
solar wind on carbon mesh sails miles wide to accelerate lightweight,
unmanned craft to speeds as high as ten percent of lightspeed. Scientists
are also working on solar sailors whose "sails" will simply be bubbles
of magnetic force. On the far edge of interstellar spacecraft design
are even more "breakthrough propulsion projects" -- theoretically
intriguing, but requiring revolutionary insights into physics and
the fabric of space-time. These include ideas to utilize "zero point
energy" essentially, the background buzz of the universe
to explore possible applications of black hole physics, to
understand the relationship between the electromagnetic spectrum
and gravity, and to theorize about warping the spacetime continuum.
Armstrong's boot hit
moondust on 20 July 1969. Thirty-three years later, we have not
yet visited any other planets. This is not a lack of technology,
but a lack of public and political will. Space exploration is expensive,
and, given real and serious problems here on Earth, less politically
aerodynamic than it was during the Cold War. Early NASA culture
had internalized the von Braun strategy for interplanetary exploration:
this assumed a monumental staged effort, stairstepping from large
infrastructure to large infrastructure build rockets, then
build a space station, next a Moonbase, and finally launch to Mars.
Obviously, the magnitude of this approach renders it astronomically
expensive. The manned Mars proposal Bush rejected so resoundingly
in 1989 featured $450 billion worth of expenses. The "smaller, faster,
cheaper" use of robotic exploration devices during the 1990s reflected
the resulting innovation of economic necessity.
An alternate strategy
for manned missions to Mars, called the "Mars Direct" approach,
was championed by Robert Zubrin in his 1996 book, The Case for Mars.
Taking lessons from history successful explorers lived off
the land it proposes unmanned flights to Mars in advance
of manned flights: first send robots to Mars to process fuel from
the immediate environment, to build habitats, and to land return
vehicles. Then send people. Could we mount a manned expedition by
2015? NASA estimates it will cost $50 billion, and does not wish
even to consider it until 2020. Yet on 5 July 2002, the Russians
suggested a $20 billion collaborative effort between NASA, ESA,
and themselves aimed at launching a manned mission by 2015.
We are curious; we are
adventurers, tool-creators, games players, problem-solvers, and
visionaries. When isolated and deprived of stimulus, we languish;
when in good company and free to explore, we thrive. The first person
to set foot on Mars has already been born: the rest of us must simply
commit to sending her.
"Komerex tel khesterex."
An old Klingon proverb: grow, or die.
("komerex," literally, ''the structure which grows'' [overtones
of "path,'" or even "Tao"]; and "khesterex," literally, "the structure
which dies." From John M. Ford, The Final Reflection.)
Internet Special Interest Group:
NASA Institute for Advanced Studies:
NASA Breakthrough Propulsion Projects:
"Warp Drive When?"
Assorted Mars links:
Explorer I, NASA's first Earth satellite, documented existence
of Van Allen radiation belts around Earth.
1969, the Eagle landed on the Moon.
1971, Mariner 9 orbited Mars and photographed it.
1973, Skylab launched.
1976, Voyagers I and II orbited and landed on Mars, giving
us the first surface photos.
1981, Space Shuttle's first mission, STS-1.
1990, Hubble Space Telescope launched.
1993, contact lost with Mars Orbserver, launched in 1992.
1996, Mars Global Surveyor lauanched.
1997, Mars Pathfinder lands on Mars on July 4, and releases
exploration robot Sojourner.
1998, Mars Global Surveyor achieves areosynchronous orbit,
begins mapping Mars.
1999, Mars Climate Orbiter, launched in 1998, fails to achieve
1999, Mars Polar Lander fails due to software error.
2001, International Space Station welcomes first residents.
2003, Mars Exploration Rover mission, featuring two flights
sending identical Athena geological sciences payloads to Mars,
2004, MER two-rover mission arrives on Mars.
2005, self-healing, evolvable on-board flight computers increase
system reliability and safety;
-- telecoms satellites "piggyback" on bi-annual Mars missions;
-- first Mars lander/rover missions with built-in terrestrial
2007, permanent robotic presence on Mars.
2015, proposed joint international manned mission to Mars.
2016, launch window for "fast transit" (130 days) to Mars.
2020, NASA's proposed horizon for a manned Mars mission.