On Catholic Christmas Jupiter and Saturnwill appear before earthlings in the form of a double planet. Such a phenomenon will occur for the first time since the Middle Ages - a similar previous parade of planets took place on March 4 in the distant 1226, or almost 800 years ago. It is noteworthy that the time of the closest approach of Jupiter and Saturn falls on the days of the winter solstice and will continue from December 16 to 25.
At this time of the planet, for an observer from Earth,will share a distance less than the diameter of the full moon, and at the closest approach on December 21, this distance will be only 20% of the diameter of the moon. According to astronomers, for the average observer, these planets will simply merge into one point. At the same time, observations through a telescope will make it possible to distinguish not only the planets themselves, but also their largest satellites.
The most convenient place to observean unusual parade of planets is the equatorial zone. When the observer moves to the north, there is a decrease in the angle at which the planets will be visible from the Earth. The approaching Jupiter and Saturn can be observed during the period from December 16 to 25 in the western sector of the sky immediately after sunset.
Inhabitants of the northern regions, for example,at the latitude of London or New York, they will be able to see planets just at an altitude above the horizon in the range from 5.3 to 7.5 degrees. Then the planets will disappear over the horizon. The best time for inhabitants of high latitudes to observe will be the first hour after sunset.
It is noteworthy that the next convergence of Jupiter and Saturn can be seen in 60 years in 2080. However, then the break will be 320 years, and the next parade of planets will take place in 2400.