Sunday, January 4, 2015

O Star of Wonder, Star of Night

"The heavens are telling the glory of God"
Psalm 19(18)

"A star shall come forth out of Jacob and a scepter shall rise out of Israel"
Num 24:17

In the Liturgical Calendar there appears to be precisely one day where my specialty (astronomy) is particularly relevant, and since I haven't written a post for the blog for a little more than a year, I have no excuse to not write one now. The feast is the Epiphany, when we celebrate the magi travelling to see the Christ child, after seeing what has become known as the star of Bethlehem.

So, this is when I should apply my special training in astronomy and explain to you what the star is. What exactly did the magi see? Short answer: I don't know. However, there is no shortage of people who claim they have the answer. Generally we can divide them into those that think the star was a purely supernatural event and those that think it was a natural astronomical event. Of course, I'm not including those who think the whole story of the magi is merely a quaint fable, or those that think it was a UFO.

Adoration of the Magi. 19th century. The star shines a beam of light toward the Christ child.
In considering the various theories, let's start with the text where we find the story:

Now when Jesus was born in Bethlehem of Judea in the days of Herod the king, behold, wise men from the East came to Jerusalem, saying, "Where is he who has been born king of the Jews? For we have seen his star in the East, and have come to worship him." ... Then Herod summoned the wise men secretly and ascertained from them what time the star appeared; and he sent them to Bethlehem, ... When they had heard the king they went their way; and lo, the star which they had seen in the East went before them, till it came to rest over the place where the child was. When they saw the star, they rejoiced exceedingly with great joy; and going into the house they saw the child with Mary his mother, and they fell down and worshipped him. Then, opening their treasures, they offered him gifts, gold and frankincense and myrrh.

Matt 2:1-2,7-11, Revised Standard Version Catholic Edition. Emphasis mine

Notice that the text does not mention several things that we commonly think of as elements of the story. The text does not say how many wise men there were, let alone name them. It does not say they were kings. Rather it seems they were astrologers. It does not say they rode on camels. It does not say the magi found Jesus in a manger, but in a house. It does not say they followed the star to Judea. Rather, they saw the star in their homeland first, and went to Jerusalem to ask Herod where the king was to be born. Then, on their way to Jesus, they saw the star a second time over where they were heading.

The text does give a number of clues about what the star might be, but not enough, I think, to definitively say what it was. Also, what clues you see in the text depend on how you interpret the text. So, it turns out, you don't need an astronomer to unravel this mystery, but someone who can read Biblical Greek. For that, I would point you in the direction of Jimmy Akin.

If we go along with the tradition that the star lead the magi on their journey (by the nose), and even pointed them directly to the house where Jesus was, then we will have to conclude that the star was supernatural. Normal stars don't behave this way, and they certainly can't point out a particular house. This is the conclusion of a number of Church Fathers (e.g. St. John Chrysostom ). Maybe it was an angel or something like the pillar of fire and cloud that led the Israelites through the desert.

But if this is the case, then I don't get to say anything about astronomy. So, let's assume the magi were not led by the star in this way, and see what astronomical explanations present themselves. The options usually listed are comets, supernovae, and planets (during conjunctions).

  • Comets are hunks of ice and rock in very elliptical orbits of the sun. They become visible when they are near the sun, and can make for spectacular shows in our night sky.
  • Supernovae are exploding stars. One way this can happen is a large star runs out of fuel, collapses in on itself, and then rebounds out. On Earth, it would look like a new star had appeared in the sky one night and then disappear after a few weeks or months.
  • A conjunction occurs when two or more celestial objects appear close together in the sky, sometimes close enough that they appear to merge into one object. These are not very rare, but astrologers may have ascribed meaning to certain groupings of objects.
Adoration of the Magi by Giotto c. 1306. In this painting the star of Bethlehem is a comet.

A complication in looking for historical instances of these astronomical events is that people tend to disagree about when Jesus was born. Depending on which date they like, people look for and sometimes find these types of events in windows of either 7 - 4 B.C. or 3 - 1 B.C.

I think the most attention has been given to planets, because they move in the night sky a bit differently than the stars. This allows them to have more interesting behavior than stars, which may have interested astrologers. The movement of stars over the course of a night is due to the Earth's rotation. This means that stars far from the North Star rise in the east and set in the west, just like the sun. Planets do the same, except that they are also orbiting the sun, so they move westward a bit faster than the stars do. If you looked at the same part of the sky at the same time every night, you would see the planets move relative to the stars, a little more west each night. Except you would sometimes see the planets stop their motion relative to the stars, backtrack a bit, and then move westward again. This is called retrograde motion. A triple conjunction can happen when a planet has a sequence of three conjunctions with the same object before, during, and after exhibiting retrograde motion.

When people ask me about the star of Bethlehem, they sometimes ask about a particular video, in which Frederick A. Larson, a lawyer, presents a case that a certain sequence of conjunctions of Jupiter matches the clues in the text. In 3 B.C., there was a triple conjunction of Jupiter and the star Regulus, both of which were associated with kingship. Later in 2 B.C., Jupiter has a conjunction with Venus, close enough that they would have appeared to merge into one object. In December 2 B.C., Jupiter would have appeared generally toward the South at night, so the magi travelling south from Jerusalem to Bethlehem would have said it was above where they were heading. Larson also thinks that the part of the text where the star "came to rest" was talking about a stopping point in Jupiter's retrograde motion. You can read about Larson's argument at his website. You can also watch a video of the conjunctions in his theory.

I find Larson's argument plausible, and it seems more developed than other theories I've seen. I think, though, that he reads into the text more requirements for the star's behavior than necessary, particularly when it comes to the part where the star "came to rest." Jimmy Akin points out that the Greek text does not imply an unusual stopping of the star. So, when you take out the requirements that are not necessary, there may be quite a few objects that would work, without any way to decide in favor of just one.

So, we are back to my short answer. What was the star? I don't know. It might be Jupiter as Larson argues. It might have simply been a miracle. I don't think the text gives enough clues to say anything for certain, though it is fun to speculate. Regardless, the story of the magi is well worth reflecting on. As the bumper sticker says, wise men still seek him!


  1. This is really well written- I love apologetics and learning how science and religion are compatible friends. Interesting how everything aligned for the birth of our Savior and to recognize that we are finite beings with a very limited view of the infinite truth. Great painting of Saint Barbara - Michael, my favorite so far! Happy 2015- looking forward to your future posts.

  2. Thanks, Matt. This post deserves a bookmark as a good and useful overview. Even more, I particularly value the way that you show just how far we can know, and where (legitimate) speculation begins. In the words of one of my favorite poets, Alexander Pope, you here "mark that point where Sense and Dulness meet" (51). Indulge me in a longer quote from the same "Essay on Criticism" (published 1711) showing the limits of intellectual activity and narrow specializations. Read these lines in an acerbic tone:
    One Science only will one genius fit;
    So vast is Art, so narrow human wit:
    Not only bounded to peculiar arts,
    But oft in those confin’d to single parts.
    Like Kings we lose the conquests gain’d before,
    By vain ambition still to make them more:
    Each might his sev’ral province well command,
    Would all but stoop to what they understand. (60-67)

    So, there's a reminder of our mental limits to inspire intellectual humility & restraint--and yet of course we, collectively and individually, do long to know more. Psalm 8 and also Augustine's opening lines on the "restless heart" remind me of how we are spurred on to seek and know ever more, in both depth and breadth. May we do so faithfully.
    May the magi (whether or not they went by the names of Melchior, Caspar, and Balthazar!) pray for all of us as we seek the Christ Child on our journeys, both intellectually and spiritually. Thanks again.