Astro 16 Blog: Blog #23: Astronomy & the Bible

In the beginning of the New Testament in the Bible, the events leading up to and following the birth of Jesus are recorded. One of the events that is described is the visit of the wise men, or magi. Matthew 2:9 says that a star in the night sky "went on before them until it came and stood over the place where the Child was" -- essentially guiding the wise men to the exact location where Jesus was born. While this is definitely a cool way for the magi to figure out where they're going, based on a modern understanding of astronomy, it seems a little weird. Sure, the North Star and the Southern Cross were often used in navigation, but in more of an orienting fashion. What kind of star (or other celestial body) appears out of nowhere, guides you where you need to go, and then disappears when it's no longer useful -- and where can I get one?

Several explanations have been presented in light of our present-day knowledge of astronomy. One idea is that the "star" could have been an alignment of Jupiter with Saturn and/or Mars, which would create a transient star-looking object. Since planets at this time were thought of as "wandering stars," it's possible that as they moved, they would appear to guide the wise men on their journey. A nova or a supernova is another candidate, since it would appear like a bright star and then eventually fade away.

A comet may seem to "point" at a specific location

Since we know the approximate date range of Jesus's birth (somewhere between 4-7BC), the location of his birth (Bethlehem), and where the magi were coming from (from east of Bethlehem), some of these suggestions can actually be cross-checked with observations that were recorded at the time. For example, one suggestion is that the celestial object was actually a comet rather than a star. A comet with the appropriate orientation was indeed observed by Chinese astronomers in 5BC -- although comets are not particularly rare, and they were actually considered bad omens at the time, making it unlikely that the magi would have followed this one.

One of the cool things about astronomy is that it's such an old field, and people have been making observations for millennia. Although we may never know the exact truth behind the magi's star, I still think it's awesome that we can think about it in astronomical terms, both theoretically, and in light of 2000-year-old observations.