By Carl Sagan
The Pale Blue Dot of Earth
This image of Earth is one of 60 frames taken by the Voyager 1 spacecraft on February 14, 1990 from a distance of more than 6 billion kilometers (4 billion miles) and about 32 degrees above the ecliptic plane. In the image the Earth is a mere point of light, a crescent only 0.12 pixel in size. Our planet was caught in the center of one of the scattered light rays resulting from taking the image so close to the Sun. This image is part of Voyager 1’s final photographic assignment which captured family portraits of the Sun and planets.
“Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there-on a mote of dust suspended in a sunbeam.
The Earth is a very small stage in a vast cosmic arena. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot.
Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.
The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.
It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.”
Consider again that pale blue dot we’ve been talking about. Imagine that you take a good long look at it. Imagine you’re staring at the dot for any length of time and then try to convince yourself that God created the whole Universe for one of the 10 million or so species of life that inhabit that speck of dust.
Our ancestors lived out of doors. They were as familiar with the night sky as most of us are with our favorite television programs. The Sun, the Moon, the stars, and the planets all rose in the east and set in the west, traversing the sky overhead in the interim.The motion of the heavenly bodies was not merely a diversion. For gatherers, as well as for agricultural peoples, knowing about the sky was a matter of life and death.
How lucky for us that the Sun, the Moon, the planets, and the stars are part of some elegantly configured cosmic clockwork! It seemed to be no accident. They were put here for a purpose, for our benefit. Who else makes use of them? What else are they good for? And if the lights in the sky rise and set around us, isn’t it evident that we’re at the center of the Universe? These celestial bodies–so clearly suffused with unearthly powers, especially the Sun on which we depend for light and heat–circle us like courtiers fawning on a king. Even if we had not already guessed, the most elementary examination of the heavens reveals that we are special.
The Universe seems designed for human beings. It’s difficult to contemplate these circumstances without experiencing stirrings of pride and reassurance. The entire Universe, made for us! We must really be something. This satisfying demonstration of our importance, buttressed by daily observations of the heavens, made the geocentrist conceit a transcultural truth–taught in the schools, built into the language, part and parcel of great literature and sacred scripture.
Dissenters were discouraged, sometimes with torture and death. It is no wonder that for the vast bulk of human history, no one questioned it. Aristotle, Plato, St. Augustine, St. Thomas Aquinas, and almost all the great philosophers and scientists of all cultures over the 3,000 years ending in the seventeenth century bought into this delusion.
Some busied themselves figuring out how the Sun, the Moon, the stars, and the planets could be cunningly attached to perfectly transparent, crystalline spheres, that would explain the complex motions of the celestial bodies so meticulously chronicled by generations of astronomers. never mind how many kings, popes, philosophers, scientists, and poets insisted on the contrary–the Earth through those millennia stubbornly persisted in orbiting the Sun.
You might imagine an uncharitable extraterrestrial observer looking down on our species over all that time–with us excitedly chattering, “The Universe is created for us! We’re at the center! Everything pays homage to us!”–and concluding that our pretensions are amusing, our aspirations pathetic, that this must be the planet of the idiots. But such a judgment is too harsh. We did the best we could. There was an unlucky coincidence between everyday appearances and our secret hopes. We tend not to be especially critical when presented with evidence that seems to confirm our prejudices.
Philosophy and religion cautioned that the gods, or God, were far more powerful than we, jealous of their prerogatives and quick to mete out justice for insufferable arrogance. At the same time, these disciplines had not a clue that their own teaching of how the Universe is ordered was a conceit and a delusion.
Every other proposal, and their number is legion, to displace us from cosmic center stage has also been resisted, in part for similar reasons. We seem to crave privilege, merited not by our work, but by our birth, by the mere fact that, say, we are humans and born on Earth. We might call it the anthropocentric–the “human-centered”–conceit. This conceit is brought close to culmination in the notion that we are created in God’s image: The Creator and Ruler of the entire Universe looks just like me. My, what a coincidence. How convenient and satisfying!
The 6th Century B.C. Greek philosopher Xenophanes understood the arrogance of the perspective. Here’s what he said: “The Ethiopians make their gods black and snub-nosed; the Thracians say theirs have blue eyes and red hair. Yes, and if oxen and horses or lions had hands, and could paint with their hands, and produce works of art as men do, horses would paint the forms of the gods like horses, and oxen like oxen.”
The immense distances to the stars and the galaxies mean we see everything in space in the past, some as they were before the Earth came to be. Telescopes are time machines. Long ago, when an early galaxy began to pour light out into the surrounding darkness, no witness could have known that billions of years later, some remote clumps of rock and metal, ice and organic molecules would fall together to make a place called Earth. Or that life would arise and thinking beings evolve, who would one day capture a little of that galactic light, and try to puzzle out what had sent it on its way.
And after the Earth dies some 5 billion years from now, after it is burned to a crisp or even swallowed by the Sun, there will be other worlds and stars, and galaxies coming into being, and they will know nothing of a place once called Earth. Those worlds in space are as countless as all the grains of sand in all the beaches of the Earth. Each of those worlds is as real as ours. In every one of them there is a succession of incidents, events, occurences, which influence its future. Countless worlds, numberless moments, an immensity of space and time.
And on our small planet, in this moment, here we face a critical branch point in history. What we do to our world, right now, will propagate down to the centuries and powerfully affect the destiny of our descendants. It is well within our power to destroy our civilization and, perhaps, our species as well. If we capitulate to superstition or greed, or stupidity, we can plunge our world into the darkness deeper than a time between the collapse of classical civilization and the Italian Renaissance.
But we are also capable of using our compassion and our intelligence, our technology and our wealth to make abundant and meaningful life for every inhabitant of this planet; to enhance enormously our understanding of the universe and to carry us to the stars.