It’s hard not to be sentimental about a Northern Hemisphere December, with its snow (or in the American South, where I live, its relative cool), its coziness, and of course, the Christmas decorations. Twinkling lights transform city streets into galaxies, and an ornamented Christmas tree fills my living room with the scent of pine needles.

On top of that tree rests a star. Some people cap their trees with an angel, but for as long as I can remember, I’ve gravitated toward the star, which represents one of the more enigmatic elements of the already peculiar narratives about Jesus’ birth.

Matthew’s gospel tells us that after Jesus was born, wise men from the East traveled to Bethlehem to worship him. Unlike the shepherds, who received a divine birth announcement from a company of angels, the wise men identified a single star rising in the sky as the impetus for their pilgrimage: “We saw his star when it rose and have come to worship him” (2:2).

It’s a detail that raises far more questions than it answers. Theologians and astronomers alike continue to contemplate Yuletide mysteries like the star of Bethlehem, but a different question is at the forefront of my mind this Christmas season: If that same star appeared in the night sky today, would we even be able to see it?

I first began to think about stars and their place in our modern world while studying another passage of Scripture in which celestial bodies play a prominent role. In Genesis 12, God makes a covenant with a man named Abram.

God promises to make Abram into a great nation, a promise that seems improbable since Abram has no children and his wife is barren.

Years pass, and Abram’s nomadic household has yet to resemble anything like a nation, let alone a great one. He still has no heir and no land to call his own, so he asks God for a sign to assure him that he hasn’t believed these promises in vain.

God instructs Abram to step outside his tent and gaze into the ...