Now the discovery last month of seven Earth-sized planets orbiting a nearby dwarf star, Trappist-1, has brought us not just a step, but a leap closer to answering that question.
“The discovery gives us a hint that finding a second Earth is not just a matter of if, but when,” said Thomas Zurbuchen, associate administrator of the Science Mission Directorate at NASA.
Proof of life on one of any of the planets orbiting Trappist-1 would answer the big question of whether we are alone in the universe. But it also would raise many more, some with theological implications.
“I have always seen the search for life elsewhere to be an opportunity to understand basically the way we relate to the universe — sort of our location,” said the Rev. Lucas Mix, an Episcopal priest and astrobiologist who has a doctorate in evolutionary biology.
“My greatest hope would be that we find life somewhere else because when we find life somewhere else, we can start to talk about what it means to be alive and not what it means to be us.”
Throughout the history of theology, Mix said, Christians have swung between the idea that Earth can be the only inhabited planet because God favours humans, and its counterpart, that to assume Earth is the only inhabited planet is the height of human pride because God is limitless and all-powerful.
The astrobiologist-priest doesn’t see the life on other planets as a challenge to the idea God loves humans and created them on this planet.
Neither do people in other traditions.
A survey of more than 1,300 people of all faiths and no faiths in 2011 found most don’t believe proof of extraterrestrial life would cause them a crisis of faith.
“It’s important to realize that Scripture is really clear only about one thing when it comes to creation: that God did it,” said Br. Guy Consalmagno, director of the Vatican Observatory and co-author of Would You Baptize an Extraterrestrial? ... and Other Questions from the Astronomers’ In-box at the Vatican Observatory.
To Consalmagno, the most exciting aspect of the discovery is the fact the planets are so close to the star they orbit “we have no idea how that’s even stable,” he said. That’s going to tell scientists more about how planets form.
In that way, science and religion are more alike than different.
“People get really, really excited about apparitions of saints and the Virgin Mary or whatever sounds spectacular, but in real life, your ordinary prayer life is frankly much richer and much more important than any presumed apparition that may or may not have occurred,” he said.
“That’s the way it is in science. Really, the everyday, step-by-step progress in the long run is much more exciting.”