Scientists have discovered a planet in the “habitable zone” orbiting around a red dwarf star, Gliese 581, which is 20 light years from earth. Scientists are not saying that the planet is inhabited or even that it has life, but they do say that it may have surface water, which is a necessary condition for life as we know it.
For year scientists have debated the possibility of life on other planets, especially intelligent life. On one side were scientists such as Carl Sagan who believed that hundreds or perhaps thousands of planets have intelligent life. On the other side are defenders of the anthropic principle who argue that the chances of intelligent life evolving are so slim that the earth may be the only planet with intelligent life in the universe. I’m sure there are some scientists out there who believe in intelligent life, but only on a few planets, or who believe there is life outside earth, but not intelligent life.
Suppose there are intelligent creatures on other planets. Would this have any implications for theology? This issue is not widely discussed today, but was a popular topic in the 1940s and 1950s. Both Pope Pius XII and Pope John Paul II were open to the possibility of intelligent extraterrestrial life. In 2008 the Head of the Vatican Observatory, Fr. Jose Gabriel Funez, said that the existence of extraterrestrial life poses no problem for Christianity. Then in 2009 the Pontifical Academy of Sciences sponsored a conference in astrobiology concerning implications for the existence of extraterrestrial life in its broadest sense (as opposed to specifically intelligent life) for Catholic theology.
Outside Roman Catholicism, the Anglican C. S. Lewis speculated concerning extraterrestrial life in his Perelandra science fiction trilogy. He was open to the possibility that other worlds may contain creatures who are, unlike human beings, unfallen. But what if creatures on another world were fallen? There is no barrier to a second Incarnation of Christ if needed, or perhaps God found some other fitting way to bring salvation to another fallen world.
The important point is that Christians should not worry should we ever discover extraterrestrial life, either non-intelligent or intelligent–such a discovery would not be a threat to Christian belief.