What is analms, and why does the sun do not coincide with the clock
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When you were in elementary school, you probably had to look at the old globe, which was invented long before Google Earth. Watch and ask the question: what kind of strange figure in the form of an eight is visible on the globe on the side? Your teacher most likely had no idea what it was. And you probably received the response of the species from him: “This is the calendar”.
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This mysterious eight is actually called Analem, and it monitors the movement of the sun in the sky during the year. In general, the measurement of time is far from always the measurement of movement forward, as it seems to us all. Our modern calendars and watches are nothing more than types of compromise: we are in a constant battle for the synchronization of these devices with heaven.
Throughout human history, the daily flow of time was determined by the movement of the sun. The noon occurs when the sun reaches the highest point over the local horizon, crossing the northern or southern meridian. The problem is that the time of passing the sun through the sky does not always correspond to the time of one turn of the Earth around its axis, that is, it does not coincide with 24 hours. In October, the sun reaches the highest point above the horizon 16 minutes earlier, in February 12 minutes later.
And why is the annoying universe it does not want to remain constant?
And such a discrepancy arises due to two important factors: due to the elliptical orbit of the Earth, and because of a certain angle at which the axis of our planet is inclined to the ecliptic plane. Of these two factors, it is the inclination of the axis of the planet that plays the paramount role, and the ellipticity of the orbit is in the background. If the orbit of the Earth was an ideal circle, and its axis would always be strictly perpendicular to the plane of the orbit, then no seasonal discrepancies in time were observed. But not one of the planets known to science is in such ideal conditions.
Is it possible to build an analem on your own? Yes, you can make it by simply fixing the position of the sun in the sky at the same time daily. During this procedure, it is important not to forget about the transitions to the winter and vice versa (if you live where this archaic practice is still observed). And it is best to start this project in winter, on the day of the December solstice, since it is on this day that the midday sun takes place at the lowest point above the horizon.