It is one of the central and most enduring elements of the Christmas story - the sighting of a bright star in the skies guiding the Wise Men to Bethlehem and heralding the birth of Christ.
The Vatican believes one explanation for the Star of Bethlehem may have been what is known as a "great conjunction" of planets, in this case bringing Venus and Jupiter in close alignment and creating a bright light in the sky above the Holy Land.
The cosmic phenomenon, which could have caused awe and wonder more than 2,000 years ago, is set to take place again, just four days before Christmas.
The closest approach of two planets since 1226 will take place on Monday, when Jupiter and Saturn come into alignment, creating what will be the spectacle of an apparently single bright star.
In an online lecture on Thursday evening, one of the Catholic Church's most eminent scientists said the latest great conjunction may provide clues to enhance our understanding of the story of the Star of Bethlehem.
"Every year, people ask us astronomers, what was the star?" said Brother Guy Consolmagno SJ, a planetary scientist and director of the Vatican Observatory, in a BBC Sky at Night virtual lecture.
"This year is special as one of the more popular explan- ations for the star is a close conjunction of bright planets, and it is going to be visible to anybody with a clear sky."
Several conjunctions of the planets happened within 10 years of the chronological point now taken as the beginning of the Christian era and may have been responsible for the phenomenon of the bright star above Bethlehem.
One was a conjunction of Venus and Jupiter in 2BC, which, according to the Encyclopedia Britannica, "would have appeared to observers in Babylon to have merged just before setting in the general direction of Bethlehem to the west".