Seeking A Star in The East

Mathews found two possible supernovas in the right period but said one was probably too low on the horizon to be seen. The other supernova is known as Kes 75. But it was 60,000 light-years away and might not have been particularly spectacular.

"There's no real convincing evidence this happened right at 2,000 years ago, but it could be in the range of being right because it's in the right location," he said.

He also found a number of novas that also could have been the Christmas star. The one he considers the most likely candidate is known as Nova Aquilae V603. The problem with novas and comets, though, is that they were believed in ancient times to be signs of disaster, not portents of good things.

For that reason, Mathews said he thinks the Christmas star is most likely an alignment of planets. He said there are three likely times for this:

• Feb. 20, 6 B.C., when Mars, Jupiter and Saturn aligned in the constellation Pisces.

• April 17, 6 B.C., when the sun, Jupiter, the moon and Saturn aligned in the constellation Aries while Venus and Mars were in neighboring constellations.

• June 17, 2 B.C., when Jupiter and Venus were closely aligned in Leo.

Mathews called the April 17, 6 B.C., alignment the most likely candidate. It makes sense because, he said, he thinks the wise men were Zoroastrian astrologers who would have recognized the planetary alignment in Aries as a sign that a powerful leader was born.

"In fact, it would have even meant that [the leader was] destined to die at an appointed time, which of course would have been significant for the Christ child and may have been why they brought myrrh, which was an embalming fluid," Mathews said. "Saturn there would have made whoever was born as a leader a most powerful leader because Saturn had the strength to do it, in their view."

Mathews has been sharing his findings in public lectures at Notre Dame and plans to write a paper to submit to the Quarterly Journal of the Royal Astronomical Society. He's also considering writing a book.

Mathews concedes, though, that any of the other events could have been the famed star. Unless a document is discovered that allows historians to more accurately estimate when Jesus was born, it will be impossible to say what caused the light with absolute certainty, Mathews said. "I think it would take more of a historical reference more than an astrophysicist," he said. "There are plenty of strong opinions out there. I think this is as good as you can do for now."