On the darkest day of the year, the winter solstice of 21th December, after almost 800 years the "comet of Bethlehem". Despite the name, however, this event has little to do with the Christmas. It is not in fact the comet that guided the King Magi towards the hut of the newborn Baby Jesus, but of an astronomical phenomenon involving the planets Saturn e Jupiter. This very rare event is given by the superposition of the two planets, which produces a kind of bright trail, just like that of the biblical comet.
Comet of Bethlehem: the effect of the conjunction between Jupiter and Saturn
The conjunction of Jupiter and Saturn, in reality, is not such a rare phenomenon, in fact it happens every 20 years. The rarity, on the other hand, lies in its strong intensity, which produces the "comet" effect. A "great conjunction"Between the two planets, similar to that of next December 21, occurred in 1226. In 1623, however, despite the strong intensity of the astronomical event, this was not visible to the naked eye due to the proximity of Jupiter and Saturn to the sun. Furthermore, although they may seem close to the naked eye, the two planets will be located at hundreds of km away from each other.
If you are unable to observe the great conjunction of Jupiter and Saturn live, theINAF (National Institute of Astrophysics) will broadcast an event live on Facebook e YouTube Entitled "Jupiter and Saturn: the meeting of the giants". This will be broadcast from 17 am to 19 pm (the best two hours in which to observe the "comet"). For many of us, this is the only opportunity to witness this astronomical effect. The next conjunction between the two planets with this particular effect is indeed foreseen in 2080.
Shortly after sunset, watching in a southwest direction, we will then be able to observe the "Comet of Bethlehem" in all its splendor (clouds permitting). Also, the fact that this conjunction occurs a few days before Christmas, in a year so tragically marked by Covid-19, by most believers it could also be seen as a very significant event. The 21th December we raise the eyes to the sky and to enjoy the comet effect of the conjunction between Jupiter and Saturn and finally say goodbye to 2020, a year to truly forget. This winter solstice, theat night it will be less dark (and we hope our future is like that too).