From The Essence of Perfection:
Another possibility is that the Star of Bethlehem may have been a nova or supernova. Nova means “new” in, referring to what appears to be a very bright new star shining in the sky; the prefix super distinguishes supernovas from ordinary novas, which are far less luminous. Supernovas are more than a nova. Sir Colon Humphreys downplays the nova theory:
According to Sir Colin Humphreys, “The first suggestion that the star of Bethlehem was a nova or a supernova was made by Foucquet in 1729, and possibly earlier by Kepler in 1614 . . . A nova or supernova satisfies the requirement that the star of Bethlehem was a single star which appeared at a specific time, but cannot account for the star moving through the sky. Similarly, all other suggestions for the star of Bethlehem (e.g. that it was Venus, etc.) can be ruled out except one, a comet.
Nova are relatively frequent appearances of a “guest star.” They turn on and off over a period of years. Novas occur in binary star systems in which one star is a normal star while the other is a compact white dwarf. A dwarf star is the remnant of the death of a star like the Sun, in which about half of the mass of the Sun has been compressed to a millionth of its volume, making a dense object about the size of the Earth. Hydrogen-rich gas pours from the normal star into an accretion disk around the white dwarf and then builds up a shell of material on the surface of the white dwarf. As this material accumulates, it becomes hotter and denser. Eventually, it ignites into a thermonuclear explosion, which causes the star to light up for days or weeks as material is ejected from the star.
It has been suggested that a supernova or nova could not be the Star of Bethlehem because the death of a star was not considered a good omen by the ancients. But taking a philosophical approach, the death of an old star, or regime, could also activate the creation of new stars—a new regime. It must be remembered that Jesus was not well received by the old regimes; in fact, it was the Romans who crucified him, only to later succumb themselves to Christianity, and it was the Jewish authorities who denied him, only to have their power weakened in later generations by the Christians, now more powerful with support from the Gentile world. However, there are still other celestial objects that the Star of Bethlehem could have been.
THE COMET OF BETHLEHEM?
Origen was one of the first theologians to suggest that the Star of Bethlehem may have been a comet or had comet-like qualities. He speaks of this in Contra Celsus, Book I, Chapter 58:
He writes, “The star that was seen in the east we consider to have been a new star, unlike any of the other well-known planetary bodies, either those in the firmament above or those among the lower orbs, but partaking of nature of those celestial bodies which appear at times, such as comets, or those meteors which resemble beams of wood, or beards, or wine jars, or any of those other names by which the Greeks are accustomed to describe their varying appearances. And we establish our position in the following manner.
Interestingly, the Chinese similar to the Greeks in naming them by their appearance in everyday object, called some comets “brooms.” Comets are celestial snowballs composed of ice, frozen gases (carbon dioxide, ammonia, methane, and more), rock, and dust that together form a nucleus as large as several miles across. Astronomers believe that they are left-overs from the gas, dust, ice, and rocks that initially formed the solar system around 4.6 billion years ago. When a comet’s orbit approaches the Sun, it heats up and spews dust and gases into a giant glowing head that can form a cloud called a coma, which expand out to 50,000 miles. The dust and gases from the tail of a comet can stretch away from the Sun for another 600,000 miles.
According to Humphreys,
Comets probably have the greatest dramatic appearance of all astronomical phenomena. They can be extremely bright and easily visible to the naked eye for weeks or even months. Spectacular comets typically appear only a few times each century. They can move slowly or rapidly across the sky against the backdrop of a star, but visible comets usually move through the star background at about 1 or 2 degrees per day relative to the Earth.
Humphreys also reminds us that the identification of the Star of Bethlehem as a comet originated with Origen in the third century, and was popular among Renaissance painters, including Giotto, in their depictions of the Nativity.
To date, the most valid candidate for the Star of Bethlehem is a celestial body from actual Chinese records. They report that an object of interest was observed in 5 BCE for more than 70 days. The 5 BCE date for the Star of Bethlehem also fits well with the textual evidence for the length of stay of Jesus and his family in Egypt. According to Matthew 2:13–15, after the Magi left Bethlehem, Joseph was warned that Herod planned to kill Jesus, so the family left for Egypt (a classic refuge for those trying to flee the tyranny of Palestine) and returned after Herod died. Both Origen and Eusebius state that Jesus and his family were in Egypt for two years and they returned in the first year of the reign of Herod Archelaus, one of Herod the Great’s sons, whose reign began when Herod died.
Therefore, if Herod died at the end of March, 4, BCE, the first year of the reign of Herod Archelaus would have been from April 4 BCE to April 3 BCE. Jesus and his family probably left for Egypt shortly after the Magi left Bethlehem, about April–June 5 BCE. If they stayed in Egypt a reasonable time after the death of Herod, to be absolutely sure of the news, they might have returned to Israel on, say, March 3 BCE, when traveling conditions would be good, in the first year of Herod Archelaus, having spent about two years in Egypt. Accordingly, the 5 BCE Chinese object is consistent chronologically with both Herod’s massacre of the infants and the two-year stay in Egypt, and it is the only celestial object the ancients recorded that would fit the description of the Star of Bethlehem.
187 Colin J. Humphreys, "The Star of Bethlehem—a Comet in 5 BC—and the Date of the Birth of Christ," Quarterly Journal of the Royal Astronomical Society 32 (1991), 389–407.
193 Origen, The Ante-Nicene Father, Translations of the Writings of the Fathers down to A.D. 325 Vol 4, (Buffalo: C.L. Pub. Co., 1885), 422.
194 Humphreys, “The Star of Bethlehem,” 392–3.
14 years ago I became interested in the date that Jesus was born. This led to several years of research, I quickly realized that there was no valid information that provided any real answers to this question. Since this website is getting some interest I will post from time to time some of the information I learned during this quest.