Pope's astronomer has an alien hobby

The Pope's astronomer will decide whether to baptise an alien when one has been found.

Director of the Vatican Observatory, Brother Guy Consolmagno, says he's intrigued by the hope of extraterrestrial life but entertains the idea on his own time.

"It's a fun thing to contemplate, just as I love reading science fiction, as we're playing with ideas," Brother Consolmagno said ahead of a public lecture in Adelaide on Monday.

He was a researcher at Harvard and MIT before joining the Jesuits, and will speak at the University of South Australia about how well science and religion work together.

He says his work is proof that traditional scientific research and religion can happily co-exist.

"The real point of having an observatory is to show the world that the church supports real science. So our key work is run-of-the-mill astronomy," he said.

"The great thing about the Vatican Observatory is that we don't need to worry about grants or timelines. For instance, we've had a 20-year project measuring the physical properties of meteorites."

The quest for alien life aside, Brother Consolmagno said it was quite simply fun to be an astronomer.

"The science itself is the reward," he said.