Dante the Astronomer

Back in college, I read Dante’s Divine Comedy – not just the Inferno, but all three parts, in a translation by Mark Musa. I remember that after Dante passes through Hell and Purgatory, he enters Heaven, Paradiso. In Dante’s universe, there is no distinction between “Heaven,” the realm of angels, and “the heavens,” the solar system and interstellar space. God lived, not up in the sky, but out among the stars.

As Dante the pilgrim travels outward from Earth, he passes the Moon, the Sun, and all the planets. And then – as his guide, Beatrice, prepares to lead him to the very edge of Creation – he turns around and looks all the way back home:

My vision travelled back through all the spheres,
through seven heavens, and then I saw our globe,
it made me smile, it looked so paltry there.

Fast forward over seven hundred years, to 1990. Carl Sagan, one of the preeminent astronomers of the modern era, had a request for NASA. He wanted them to reorient the camera on the Voyager 1 spacecraft, which had passed the planets and reached the edge of the solar system. He wanted our most distant pilgrim to turn around and look all the way back home.

The idea had little practical value in the strict sense of scientific research, but astronomers are nothing if not romantic. They took the picture.

Here’s what Earth looks like from three billion miles away, a single pixel floating in a ray of light:

This is the legendary Pale Blue Dot photo. As Sagan describes it:

We succeeded in taking that picture [from deep space], and, if you look at it, you see a dot. That’s here. That’s home. That’s us. On it, everyone you ever heard of, every human being who ever lived, lived out their lives. The aggregate of all our joys and sufferings, thousands of confident religions, ideologies and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilizations, every king and peasant, every young couple in love, every hopeful child, every mother and father, every 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.

As far as I know, neither Dr. Sagan nor anyone else made a conscious connection between what he had done and Dante’s epic poem. But the facts remain. In less than a thousand years, the human race took an idea that was – to a medieval writer – mere metaphysical fantasy, and built a robot to actually do it.

And that was twenty years ago. We didn’t even have the Web.

This is it, boys and girls. This is the future. We’ve arrived.