Olbers paradox is an as yet unsolved astronomical problem. It’s named after Heinrich Olbers, a Germany astronomer. It asks two questions.

The first: is the universe infinite? Does it extend outward forever in all directions?

The second is more crucial: IF the universe extends out forever, why is the sky not filled with stars? Filled day and night, filled everywhere in the sky as far as we can see? Why, in reality, is the sky not brighter than the sun everywhere we look?

Because again IF the sky goes out infinitely in every direction, there should be no spot where there’s not a star beaming down at us.

Oddly enough, Christmas makes me think of Mr Olbers. By way of a hymn that we sing every year: Away In A Manger. Specifically, the second verse.

Originally, we sang simply, “the stars in the sky,” but there’s a problem there: that line has only five syllables. Every other verse’s first line has six syllables. Which makes singing the line of that verse a little difficult. So we’ve tended to add another syllable: “the stars in the BRIGHT sky.”

But the sky – at night – is not bright. Spectacular, yes. Beautiful, yes. Impressive, yes. But not bright. Even if the moon is out, the sky is nowhere close to as bright as the sun filled sky at noon.

None of which takes away from this beautiful hymn. But all knowledge is interconnected, and the question of the heavens is a crucial part of Jesus’ birth story. So we look up at the stars at night and wonder at the beauty of the skies and wonder how far this extends out. And Mr Olbers asks us further to question what are the ramifications of that question. And remember as we start 2022 how much there is to learn. And to be humbled by our profound and very human ignorance.