The star of Bethlehem, which appeared to the Three Kings above the manger after the birth of Jesus Christ, was apparently actually the planet Venus. Alternatively, it was a conjunction of two very bright planets, either Jupiter and Venus, or Jupiter and Saturn. Astronomer Juraj Tóth from the Faculty of Mathematics, Physics and Informatics of the Comenius University in Bratislava gave this explanation to TASR as probable.
According to the Bible, the star was supposed to appear in the east, which would correspond to the situation when Venus rises above the horizon at dawn as the Dawn. “They asked where is the newly born king of the Jews? For we saw his star in the east and came to worship him,” says the Bible. In verses 9 and 10 it says: “They listened to the king and left. And behold, the star that they saw in the east went before them until it stood over the place where the child was. When they saw the star, they were filled with great joy.”
In the past, the Star of Bethlehem was also depicted as a comet. As one of the first to use this symbol, the Italian artist Giotto di Bondone (1266 – 1337) in his greatest work The Adoration of the Three Kings, which is a cycle of frescoes painted in the Scrovegni chapel in Padua. The artist completed this work in 1305. He was apparently influenced by the observation of the comet known today as Halley’s Comet, which was well visible in 1301, during his lifetime.
When the comet was photographed for the first time under its current name in 1910, it was obvious from the shape of the objects that the pre-Renaissance artist was based on his own experience. However, according to astronomers, Halley’s comet could not have appeared in the sky at the time of the supposed birth of Jesus Christ – even though it was already known at that time. It returns to the vicinity of the Earth once every 75.3 years, it was last observed in 1986.
The conjunction hypothesis was first proposed by the German astronomer Johannes Keppler. Astronomical records would also correspond to this, according to which the conjunction of Saturn and Jupiter occurred as many as three times in the year seven BC, on May 29, September 30, and December 7. At the same time, historians often indicate this year as the year when Jesus Christ could actually have been born.
Jupiter, Saturn and Venus are among the brightest objects in the sky. Saturn reaches an apparent magnitude of minus 0.5 magnitude (0.5 mag), Jupiter even – 2.9 mag and Venus – 4.9 mag. (The smaller the number, the brighter the object, that is, the brightest objects have a negative value of this magnitude.) For comparison, the brightest star in the sky Sirius in the constellation Canis Major has an apparent magnitude of – 1.5 mag, the star Vega in the constellation Lyra 0 mag, and the slightly less bright Polaris in the Little Dipper, for example + 1.9 mag. Objects with an apparent magnitude of 6 mag and higher are not visible to the naked eye.
It is comets that mostly achieve such a low brightness and can only exceptionally compete with the brightness of the mentioned planets. This happened in the case of the well-known comet Neowise in 2020. One of the theories is then a supernova explosion on February 23 in the year 4 BC – today it is known as PSR 1913+16 or the Hulse-Taylor pulsar.
An impressive conjunction of Jupiter and Venus could be observed in the spring of 2023. During these days, including during Christmas, it shines over the western horizon after sunset extra bright Venus like Vespers. It sets over the horizon only after 7:30 p.m. Central European Time (CET), specifically on Christmas Day, December 24, at 7:47 p.m. CET (data for Bratislava). In January and February, it will even set between 8 and 9 p.m. in the evening.
The planet Jupiter is well visible during this period, for example on December 24th it will rise at 2:39 p.m. and shine in the sky until the morning hours – it sets at 6:15 a.m. CET. Finally, at the turn of the year, the very bright planet Mars, characterized by its reddish or orange color. It comes out e.g. On December 24 at 6:10 p.m., it is also visible throughout the night. At the beginning of next year, on January 12, 2025, Mars will be closest to Earth, approximately 95.7 million kilometers, which is a situation that occurs approximately once every two years.
