Spaceflight and Global Unification: The Benefits of Space Exploration

Article excerpt

For more than thirty years the people of Earth have been engaged in the exploration of the planets. We have had the privilege of sharing in the excitement of discovery--not just of a new world, as the epochal exploration of half a millennium ago is termed, but of more than two score new worlds. From the cratered, dense world of Mercury to the frigid, blue world of Neptune, a myriad of unimagined discoveries has been made. Among the highlights of this exploration have been:

* the first images from the surface of Mars showing an alien world that yet looked vaguely similar to an earthly desert;

* the sulphur world of Io, with volcanoes continuously erupting on its molten surface;

* the twisted rings of Saturn, which cause us to speculate about new forces of nature;

* the bizarre structure of Miranda, whose geological patterns defy our attempts to see the overall pattern;

* the first view of that blackened, crusty, and dirty snowball--the nucleus of Earth's most famous celestial visitor, the comet Halley;

* the surface of Venus, which is hot enough to melt lead and features strange new geologic features that look like pancakes.

These and a host of other discoveries have given birth to new understandings in many sciences--physics, astronomy, geology, biology, engineering, and computer, to name some. But besides the esoteric benefits of scientific knowledge, there have also been many mundane (literally, down-to-Earth) benefits:

* The runaway greenhouse on Venus, caused by an excess of carbon dioxide in its atmosphere, has led to understanding of the dangers of carbon dioxide buildup on Earth and the resulting global climate change.

* The antiseptic surface of Mars, clean of any life or organic material because there is no ozone layer to protect it, provides a bleak description of what might happen if we destroy Earth's ozone layer.

* Finding aerosols in the atmosphere of Venus, and observing how they interact with the molecules there, has led to knowledge about what happens when we introduce aerosols into Earth's atmosphere.

* Observing and analyzing the dust storms on Mars have provided us with models of what happens to a planet's climate if massive amounts of dust are blown into the atmosphere, as would happen on Earth from a volcano, a large impact, or a nuclear holocaust.

* Asteroidal and cometary impacts on the terrestrial planets have profoundly influenced the evolution of those planets, and on Earth we now know that such impacts have wiped out species in the past and could again in the future.

Perhaps the most striking discovery, however, is the nondiscovery of life elsewhere in the solar system. In all of the many worlds in our solar system, we have found not a shred of evidence for extraterrestrial life, even though much of the stuff of life (organic molecules, chemicals, and water) are there. It is too early to draw conclusions. We haven't done enough looking. But we wonder whether our earthly existence is unique, and what special responsibility is implied.

The exploration of the solar system--the lessons, the data, the information, the knowledge gained--has been an enterprise not just for a few scientists or for one nation, but for our whole planet and for all humankind. It is natural to consider it as an earthly activity.

Its conduct, as well as its motivation, has become increasingly international. The Soviets carried out landings on Venus, while the Americans made two successful ones on Mars. The United States has landed people on the Moon and returned samples; the Soviet Union landed automatic vehicles there and returned samples robotically. The U.S. explored the outer planets; Japan, Europe, and the U.S.S.R. explored Halley's comet. Now the world has changed, and current missions are less and less national and more and more international. The next Mars landings are an international mission: Mars 94/96 will be led by Russians but with heavy involvement of Europeans. …