Faint Echoes, Distant Stars: The Science and Politics of Finding Life Beyond Earth

It goes against nature in a large field to
grow only one shaft of wheat, and in an
infinite universe to have only one living
world.

--Metrodorus of Chios Circa 400 B.C.

What is the history of life?

Are we alone in the universe?

What is the future of life?

Is life a normal part of the universe,or is our Earth the only world that harbors living creatures?

Children ask, "Where did I com from?" Stargazers wonder if there is life on any of the fiery specks that dot the night sky. Philosophers ponder the meaning of life and seek to understand our place in the greater universe that surrounds us.

These questions haunt our consciousness today, as they have for countless millennia. Human beings have always wondered about how life began and whether life exists beyond th Earth. The quest for life elsewhere in the universe is far older than written history.

THE ALIENS AMONG US

Since the beginning of human existence our ancestors have populated the world with powerful supernatural creatures. The earliest writings we know of deal with gods and goddesses who are obviously much more powerful than mere mortals and who inhabit realms far beyond this mundane world in which you and I live.

Try to see the world as our prehistoric Ice Age ancestors did. Living in small tribes of hunters and gatherers, following the game herds across the land, they faced a world of terrifying dangers. Powerful lions and leopards stalked the night. When they sought shelter in caves, often as not a ferocious cave bear would mangle them with its sharp claws and powerful, crushing teeth.Hunger was a constant threat; wild fires, bewildering attacks of disease, a broken bone, even childbirth was dangerous.

Those early hunting/gathering tribes saw no difference between the animate and inanimate. To them, everything was alive: trees, rocks, clouds, animals -- specially the animals they hunted for food and the predators who hunted them. Each and all had their own individual spirit.

They did not feel alone in a cold and uncaring universe. If anything, there were too many other creatures, real and imagined, sharing the world with them. They must have felt overwhelmed by spirits that were much more powerful than themselves. On the walls of their caves they drew hauntingly beautiful pictures of the animals they lived among, probably in an effort to gain som sort of mystical control over those wild beasts, or at least to ease som of the fear they felt when facing the animals 'fangs and antlers with nothing more than primitive weapons of wood and bone.

And they watched the night sky. Paleontologists have discovered a bone with th phases of the Moon carved into it, dating back 30,000 years.

FROM AKHENATON TO ZEUS

Farmers depend on the weather. So much so that the earliest farmers believed that the forc s of the weather -- wind, rain, sun -- were gods who needed to be propitiated by prayers, sacrifices, and fertility rites. The idea that there were beings who were more than human, beings much more powerful than themselves, was well-entrenched in them by the time agriculture began to irrevocably change human society some 12,000 years ago.

In ancient Egypt the Sun was worshiped as a god. One of the earliest prayers we know of is attributed to the Pharaoh Akhenaton (circa 1370 B.C.),a prayer to the Sun that gave life to the world, which he called Aton:

Thy dawning is beautiful in the horizon of the sky,
O living Aton, beginning of life.
When thou risest in the eastern horizon,
Thou fillest every land with thy beauty.

Even wild nomadic tribes such as th Achaeans, who invaded and conquered the land we now call Greece, worshiped gods of the sky and the weather. Zeus, the chief god of their pantheon, was originally a storm god. The thunderbolt was his sign and his weapon.

Farming also depends on the seasons, and farming societies began to study the stars in an effort to predict when they should plant their crops. In ancient Egypt, where the Nile's annual flood brought fresh, fertile silt to the parched land, it was vital to know when the Nile would rise. The Egyptians learned that when the bright star Sirius rose just before dawn, the river's flood was only a matter of days away. In cloudy,dank, chilly Britain, Stone Age farmers somehow managed to build gigantic megalithic circles such as Stonehenge, which served as astronomical computers that predicted the seasons, most importantly the spring equinox, the time to plant the summer's crops. Eventually, our ancestors invented agriculture.

FROM ASTROLOGY TO LUCRETIUS

It was only natural for people to believe that the heavens had an important influence on their lives. They did! Curious thinkers wondered why this was so and how these influences could be predicted, interpreted, and used for practical everyday affairs.

Thus was born the ancient art of astrology, which attempts to predict the events of an individual's life by considering the positions of the stars and planets. It doesn't really work, but to this day most newspapers and many Internet sites carry a daily horoscope column based on ideas that were hoary with age in Julius Caesar's time.

The ancients also cam to believe that the realm of the stars must be very different from th Earth on which we live. A mental separation between Earth and sky arose, a separation that would have seemed strange to the Ice Age hunting tribes. To the average citizen of ancient Athens or Rome, this world of ours was an imperfect place, filled with pain and unhappiness.