Pale Blue Dot ( PDFDrive.com ) (1)

Nevertheless, there has been and will be no shortage of volunteers.
But why Mars? Why not return to the Moon? It's nearby, and we've proved we know how to send
people there. I'm concerned that the Moon, close as it is, is a long detour, if not a dead end. We've
been there. We've even brought some of it back. People have seen the Moon rocks, and, for reasons
that I believe are fundamentally sound, they are bored by the Moon. It's a static, airless, waterless,
black-sky, dead world. Its most interesting aspect perhaps is its cratered surface, a record of ancient
,catastrophic impacts, on the Earth as well as on the Moon.
Mars, by contrast, has weather, dust storms, its own moons, volcanos, polar ice caps, peculiar
landforms, ancient river valleys, and evidence of massive climatic change on a once-Earthlike world.
It holds some prospect of past or maybe even present life, and is the most congenial planet for future
life—humans transplanted from Earth, living off the land. None of this is true for the Moon. Mars also
has its own legible cratering history. It Mars, rather than the Moon, had been within easy reach, we
would not have backed off from manned space flight.
Nor is the Moon an especially desirable test bed or way station for Mars. The Martian and lunar
environments are very different, and the Moon is as distant from Mars as is the Earth. The machinery
for Martian exploration can at least equally well be tested in Earth orbit, or on near-Earth asteroids,
or on the Earth itself—in Antarctica, for instance.
Japan has tended to be skeptical of the commitment of the United States and other nations to plan
and execute major cooperative projects in space. This is at least one reason that Japan, more than any
other spacefaring nation, has tended to go it alone. The Lunar and Planetary Society of Japan is an
organization representing space enthusiasts in the government, universities, and major industries. As I
write, the Society is proposing to construct and stock a lunar base entirely with robot labor. It is said
to take about 30 years and to cost about a billion U.S. dollars a year (which would represent 7
percent of the present U.S. civilian space budget). Humans would arrive only when the base is fully
ready. The use of robot construction crews under radio command from Earth is said to reduce the cost
tenfold. The only trouble with the scheme, according to reports, is that other scientists in Japan keep
asking, "What's it for?" That's a good question in every nation.
The first human mission to Mars is now probably too expensive for any one nation to pull off by
itself. Nor is it fitting that such a historic step be taken by representatives of only a small fraction of
the human species. But a cooperative venture among the United States, Russia, Japan, the European
Space Agency—and perhaps other nations, such as China—might be feasible in the not too distant
future. The international space station will have tested our ability to work together on great
engineering projects in space.
The cost of sending a kilogram of something no farther away than low Earth orbit is today about the
same as the cost of kilogram of gold. This is surely a major reason we have yet to stride the ancient
shorelines of Mars. Multistage chemical rockets are the means that first took us into space, and that's
what we've been using ever since. We've tried to refine them, to make there safer, more reliable,
simpler, cheaper. But that hasn't happened, or at least not nearly as quickly as many had hoped.
So maybe there's a better way: maybe single-stage rockets that can launch their payloads directly to