You see, for most of history, people thought this Earth we stand on was the only world that existed. The sun, moon, and stars were mere lights in the sky. Certain stars that did not stay in one constellation were called “planets” (Greek for “wandering stars”). They had names like Venus, Mars and Jupiter.
Then in the 16th century, Nicolaus Copernicus proposed that the Earth circles the sun, and so do the planets. Earth and the planets had something in common.
Very quickly, people suggested that planets might have a lot in common with Earth. They might even have people on them! Why would Earth be the only peopled planet? In those days scientists thought that life spontaneously arose straight from the dirt, and that this could be observed regularly, if you knew where to look.
Then Giordano Bruno proposed that the stars were other suns, with their own planets, with people on them. By the 17th century, people were talking about the universe being full of planets with intelligent life, much like in today’s “Star Wars” or Marvel cinematic universes.
But if the universe is full of intelligent life, why would God become incarnate on this particular ball of rock? There were theological answers to this, of course, but it made for powerful rhetoric anyway.
Thomas Paine, who wrote in support of the American Revolution, asked in his book “The Age of Reason” how it could be “that the Almighty, who had millions of worlds equally dependent on his protection, should … come to die in our world, because they say one man and one woman had eaten an apple!”
He wondered if all those worlds would get such attention. If so, then “the Son of God … would have nothing else to do than travel from world to world, in an endless succession of death.” The existence of other worlds like Earth scatters Christianity in the mind, he said, “like feathers in the air.”
Plenty of other people said similar things over the centuries. Bye-bye Advent. Bye-bye Hanukkah (which just ended), too, for that matter. Why would God choose a people on this particular ball of rock?
Except … the idea that other planets would be just like Earth and other stars would be just like the sun did not pan out. Astronomers were looking for intelligent life on Mars as late as the 20th century, but there’s no life there. Nothing on Venus or Jupiter either. It turns out that, while planets do have some basic things in common, there is tremendous variety among them. Lots of them are really inhospitable to life.
In the late 19th century, astronomers began to realize that there is tremendous variety in stars, too — and that we were wrong about life just spontaneously springing from matter (we don’t observe that anywhere, actually). And in recent decades, we’ve found tremendous variety in the numerous planetary systems we have discovered circling other stars.
So now it seems our corner of the universe is a little unusual. Paul Murdin, in his 2019 book “The Secret Lives of Planets,” says that our solar system “seems to be unique … [with] no parallel among the known planetary systems.” On NASA’s exoplanets website, we hear that ours may be “the weirdest solar system we’ve found so far.”
Ta-da! Perhaps astronomy doesn’t oppose Advent after all! Of course, science is not a great basis for ideas about faith. As we have seen, science can change. Maybe someday it will change back.
But in the meantime: Happy Advent, here in this unparalleled, weird solar system — the one where God became a human being.
