Pale Blue Dot ( PDFDrive.com ) (1)

consequences of thermonuclear war were understood. By 1992, large numbers of warheads
were being dismantled.
• The first asteroid was discovered in 1801. More or less serious proposals to move them
around were floated beginning in the 1980s. Recognition of the potential dangers of
asteroid deflection technology followed shortly after.
• Biological warfare has been with us for centuries, but its deadly mating with molecular
biology has occurred only lately.
• We humans have already precipitated extinctions of species on a scale unprecedented
since the end of the Cretaceous Period. But only in the last decade has the magnitude of
these extinctions become clear, and the possibility raised that in our ignorance of the
interrelations of life on Earth we may be endangering our own future.
Look at the dates on this list and consider the range of new technologies currently under
development. Is it not likely that other dangers of our own making are yet to be discovered, some
perhaps even more serious?
In the littered field of discredited self-congratulatory chauvinisms, there is only one that seems to
hold up, one sense in which we are special: Due to our own actions or inactions, and the misuse of
our technology, we live at an extraordinary moment, for the Earth at least—the first time that a
species has become able to wipe itself out. But this is also, we may note, the first time that a species
has become able to journey to the planets and the stars. The two times, brought about by the same
technology, coincide—a few centuries in the history of a 4.5-billion-year-old planet. If you were
somehow dropped down on the Earth randomly at any moment in the past (or future), the chance of
arriving at this critical moment would be less than 1 in 10 million. Our leverage on the future is high
just now.
It might be a familiar progression, transpiring on many worlds—a planet, newly formed,
placidly revolves around its star; life slowly forms; a kaleidoscopic procession of creatures evolves;
intelligence emerges which, at least up to a point, confers enormous survival value; and then
technology is invented. It dawns on them that there are such things as laws of Nature, that these laws
can be revealed by experiment, and that knowledge of these laws can be made both to save and to
take lives, both on unprecedented scales. Science, they recognize, grants immense powers. In a flash,
they create world-altering contrivances. Some planetary civilizations see their way through, place
limits on what may and what must not be done, and safely pass through the time of perils. Others are
not so lucky or so prudent, perish.
Since, in the long run, every planetary society will be endangered by impacts from space, every
surviving civilization is obliged to become spacefaring—-not because of exploratory or romantic
zeal, but for the most practical reason imaginable: staying alive. And once you're out there in space
for centuries and millennia, moving little worlds around and engineering planets, your species has