The star of Bethlehem and the Three Kings

The celebration of Christmas prompts many people to recount the biblical story of three wise men guided to the birthplace of Jesus Christ by a bright object in the sky. There have been numerous possible scientific explanations of what the Star of Bethlehem may have been. 

It must be remembered that the Chaldeans who occupied Mesopotamia 2,000 years ago were assiduous observers of the night sky and were very familiar with the motions of the sun, moon and planets. The three kings were religious scholars known as the Magi - revered Babylonian astronomers and astrologists. They studied the stars and planets, interpreting the meaning behind cosmic events. Anything very unusual was considered an omen, so the star must have been both rare and visually spectacular, and if something very rare took place in the sky, the ancient skywatchers would have noticed it immediately.

After countless reading of articles i’ve summarised a few to ponder over:

  • One of those proposed possibilities played out in the night sky this year on August the 27th; an exceedingly close encounter between the two brightest planets, Venus and Jupiter which appears to almost touch. Venus-Jupiter encounter is one of those rare events, and something similar appeared in the sky more than 20 centuries ago. A rare apparition. The biblical account of the story of the Star of Bethlehem calls for not one, but two "stars." One to be seen at the start of the Magi's journey, while the other appearing to them upon their arrival in Bethlehem.  Interestingly, in August of 3 B.C., Venus and Jupiter were prominent in the predawn eastern sky, and on Aug. 12 they came within just 9 arc minutes (0.15 degrees) of each other as seen from the Middle East. Incidentally, this sign would have been seen by men "in the east," explaining the phrase in the Book of Matthew.  Ten months later, Venus and Jupiter got together again for an even more spectacular encore on June 17, 2 B.C., when at sundown from Babylonia they were separated by just 4 arc minutes of each other, about 35 degrees above the western horizon. As the sky grew dark, the two brightest planets drew closer to each other until finally at 9:15 p.m. local time they drew to within 36 arc seconds (0.01 degree) equal to the mean apparent width of Jupiter as seen through a telescope, at an altitude of 15 degrees above the horizon. To most people, the two planets must have appeared to coalesce into a single "star" somewhat brighter than Venus alone. The fact that Jupiter and Venus had such a close conjunction at this time in history has led some people theorize that it could be an explanation for the Star of Bethlehem. 
  • The other theory is that the star of Bethlehem was probably not a star at all, and that it was more than one single event.  Astronomer-astrologers reported omens to the king; these were anything unusual - perhaps the moon moving in front of a planet, or a lunar eclipse. Their job was to interpret the meaning of these phenomena. There was also an elite class of diviners who created nativity charts. They recorded the positions of the planets, the Sun, the Moon and other astronomical data at the time of a child's birth, in order to make predictions about that person's life.  Some believe that the wise men from the East, or the "Magi" of the nativity, were astrologers from Mesopotamia, and that the star rising in the east was the horoscope that predicted the birth of a king. If so, they were reading a nativity chart in reverse; they had the prediction and sought to find the child who had been born at that precise moment.


  • Best explanation for this series of events is something known as a triple conjunction between Jupiter and Saturn - with the two planets coming close together in the sky three times over a short period. This happens when] you get an alignment between the Sun, the Earth, Jupiter and Saturn.  Tim O'Brien, associate director of Jodrell Bank Observatory in Cheshire, suggests this would have looked striking. "It's remarkable how much your attention is drawn when two very bright objects come together in the sky," he explains.And once the planets lined up in their orbits, Earth would "overtake" the others, meaning that Jupiter and Saturn would appear to change direction in the night sky. "You would [only] get a triple conjunction like this about every 900 years," he says, so for astronomers in Babylon 2,000 years ago, it would have been a signal of something very significant."A triple conjunction of this kind ticks all the boxes."


  • Another explanation is a very bright comet.  While certainly spectacular and ethereal in appearance, comets are essentially "big, dirty snowballs" flying through space.  When they come close to the Sun, this ice melts - solar wind blows this material out into space, so you get a tail of matter coming off the comet,this tail, which points away from the Sun, is one of the things that has made the comet idea popular.  The most timely record was of a bright comet appearing in the constellation of Capricorn in 5BC, which was recorded by astronomers in China.


  • A less likely, but more famous candidate was Halley's comet, which was visible around 12BC.Those who favour this theory point out that the 5BC comet would have been in the southern sky as seen from Jerusalem, with the head of the comet close to the horizon and the tail is pointing vertically upward.


  • Another theory is that the star was light from the birth of a new star, or nova. There are records - again from astronomers in the Far East - of a new star in the small, northern constellation of Aquila in 4BC. People who like this theory say this new star would have been [positioned] directly over Jerusalem.  Dr Robert Cockcroft, manager of the McCallion Planetarium at McMaster University in Ontario says a nova is "a good candidate" for the star of Bethlehem.


From all us to you at StarsByNight, hope you have a fabulous holiday period!