People have been telling stories about the stars for a long time. We have written accounts from the ancient Egyptians and Sumerians from 5,000 years ago and references to oral traditions that date back earlier than that. Some are creation stories of the Sun, Moon, and Earth. Others tell of legendary people and animals, preserved forever in the constellations.
Beyond ancient records we can only guess, and my own guess is that we have been telling stories about the stars for as long as we have been able to talk to each other. We’re constantly creating new ones, too. Contact, Interstellar, and Arrival are just a few of the movies in which human stories play out against backdrops that include space travel, other worlds, and even other intelligent forms of life. For every movie or television show, there are many speculative fiction works.
One of the old stories in which a star plays a prominent role is most often retold at this time of year.
The Christmas Star was, according to the gospel of Matthew, a new star that appeared in the sky and led the three magi to the newborn Jesus of Nazareth. It is a lovely image and a compelling storytelling device that has left lots of us amateur astronomers wondering if there was an actual celestial event that inspired it.
At the time of Jesus’ birth, astronomy and astrology were the same discipline. Astrologers were often priests of one religion or another and were literate — an elite skill in ancient times. This gave them access to written records of astronomical events such as the appearances of comets, planetary conjunctions, and eclipses, and they were able to write their own accounts. We have access to these documents today — or rather, those of us who can decipher Aramaic, ancient Greek, and Classical Chinese have access.
Modern astronomers’ tools are more powerful and sophisticated than those of the early astrologers, but the impulse remains the same: to understand, to predict, and to appreciate.
So, what kind of event could the Christmas Star have been? Are there any records of such an event in the first year of the common era?
Comets have some qualities that make them strong candidates. They are transient, appearing suddenly and often vanishing in a short period of time. They can appear anywhere in the sky, including “in the east,” as Matthew recounts. But comets were almost universally considered bad omens. For that reason, ancient writers would not have been likely to link a comet with a figure like Jesus.
A close planetary conjunction is another possibility. This is when two planets (which to the unaided eye look like bright stars) draw unusually close to each other for a short time. But we have no ancient records of a noteworthy conjunction around 1 CE. Modern astronomers can use computers to roll back the sky to any date in history, and it seems that no close conjunction occurred at the right time and location in the sky to make that the basis of this story.
Then there are supernovae. A supernova is the explosion of a very large star. If it occurs close enough to Earth, we see it as a new bright star, which appears suddenly then fades away over a period of weeks or months. A supernova can appear anywhere in the sky. It’s the most likely astronomical event — if there was one — that the ancients might have seen and associated with this story.
The closest match we have in the historical record is a supernova recorded by Chinese astronomers. It appeared in the right part of the sky but at the wrong time — in the year 4 BCE, which is just a few years too early.
Does that end our search for a historical Christmas Star? Maybe. But the ancient world had no kitten calendars, nor easy access to Wikipedia for confirming dates. When Matthew wrote in the early first century CE, the supernova of 4 BCE was an event that some people may have still remembered. I can imagine it would have been tempting to merge the star and Jesus in memory, and that eventually people may have told the story that way, which Matthew may have then recorded in good faith.
All of this is conjecture on my part, inspired by curiosity about science and a deep respect for the proto-scientists of the ancient world. Whatever your beliefs, this is a wonderful time of year to step outside after dark and look up at the sky. The air is clear, and the stars shine brightly. Orion is climbing in the East and Jupiter is still with us in the West. We are unlikely to see a new star beckoning — but who knows? Supernovae do happen. Clear skies!