About 350,000 years ago, our species stood and looked up at the sky and wondered at what could be seen there. At dawn we saw the rising of the sun and followed its path as it rose and fell; at night, we saw the moon wax and wane amidst lights without number. I don’t know if there was ever a time when we did not feel the pull of the heavens. We have named the stars after the gods of myth and legend—or perhaps, it is better to say that we have named our gods after the heavenly bodies that rule our nights and days. We spent hundreds of thousands of years looking up at the heavens and yearning to travel in the stars. For thousands of years we worked to master metals and fuels and understand the laws of the universe. And then, on Christmas Eve, 1968, the Apollo 8 mission made a fourth orbit around the moon, and for the first time human eyes saw the Earth rise on the horizon, blue and full of life. All those years of looking at the sun, the moon, and the stars, all those years of dreaming and wondering, and for the first time human eyes looked back in wonder and saw their home, shining in the darkness of space. William Anders, took the photograph you see before you, said, “We set out to explore the moon, and instead we discovered Earth.”
There is no place like our home. We still search the heavens, although now we do it with telescopes so powerful the light they receive has passed over not only billions of miles, but passed through millions of years. We search for shadows and wobbles around stars, for rocky planets in the goldilocks zone around a star of just the right amount of power, searching for another blue dot like our own. We have yet to find one, despite our technological proficiency. Enrico Fermi, the great physicist, once thought about all vastness of space, littered with planets and asked, “Why haven’t we heard from anyone else?” This is Fermi’s Paradox—Given the amount of stars, there ought to be something more like us out there—but it seems this blue world contains all the intelligent life we can ever know. As far as we know it is unique in the universe—unique that it is just close enough to the right star, with just the right atmosphere to shelter life. Given all that we know about the universe, we also know this is all the home humans will ever have. You’d think, having walked on the moon, and seen the Earth from afar, we’d do anything to protect this planet, this home.