In popular science articles on the topics of space and astronomy, you can often find the not entirely clear term "ecliptic". This word is often used by astrologers besides scientists. It is used to indicate the location of space objects distant from the solar system, to describe the orbits of celestial bodies in the system itself. So what is the "ecliptic"?
What does the zodiac have to do with it
The ancient priests, who were still observing the heavenly bodies, noticed one peculiarity of the Sun's behavior. It appears to move relative to the stars. Tracking its movement across the sky, observers noticed that exactly one year later, the Sun always returns to its starting point. Moreover, the "route" of movement from year to year is always the same. It is called the "ecliptic". This is the line along which our main luminary moves across the sky during the calendar year.
The stellar regions were not left without attention, through which the path of the shining Helios ran in his golden chariot drawn by golden horses (this is how the ancient Greeks imagined our native star).
Circle of 12 constellations through which it movesThe sun was called the zodiac, and these constellations themselves are usually called zodiac.
If according to the horoscope you are, say, Leo, then do not look for this constellation in the sky at night in July, the month in which you were born. The Sun is in your constellation during this period, which means that you can see it only if you are lucky to catch a total solar eclipse.
Ecliptic line
If you look at the starry sky during the day (and this can be done not only during a total solar eclipse, but also with a conventional telescope), we will see that the sun is at a certain point in one of the zodiac constellations. For example, in November this constellation is most likely to be Scorpio, and in August - Leo. The next day, the position of the Sun will shift slightly to the left, and this will happen every day. And a month later (November 22), the luminary will finally reach the border of the constellation Scorpio and move to the territory of Sagittarius.
In August, it is clearly visible in the figure, the Sun will be in the boundaries of Leo. Etc. If every day we mark the position of the Sun on a star map, then in a year we will have a map with a closed ellipse drawn on it. So this very line is called the ecliptic.
And when to watch
But to observe your constellations (zodiac signs under which a person is born) will turn out in the month opposite to the date of birth. After all, the ecliptic is the route of the Sun, therefore, if a person is born in August under the sign of Leo, then this constellation is highabove the horizon at noon, that is, when the sunlight will not let you see it.
But in February, Leo will grace the midnight sky. On a moonless, cloudless night, it is perfectly “read” against the background of other stars. Those born under the sign of, say, Scorpio are not so lucky. The constellation is best seen in May. But to consider it, you need to stock up on patience and luck. It is better to go out of town, to an area without high mountains, trees and buildings. Only then will the observer be able to see the outline of Scorpio with its ruby Antares (alpha Scorpio, a bright blood-red star belonging to the class of red giants, having a diameter comparable to the size of the orbit of our Mars).
Why is the expression "plane of the ecliptic" used
Besides describing the stellar path of the annual motion of the Sun, the ecliptic is often considered as a plane. The expression "plane of the ecliptic" can often be heard when describing the position in space of various space objects and their orbits. Let's figure out what it is.
If we return to the scheme of motion of our planet around the mother star and put together the lines that can be drawn from the Earth to the Sun at different points in time, it turns out that they all lie in the same plane - the ecliptic. This is a kind of imaginary disk, on the sides of which all 12 described constellations are located. If a perpendicular is drawn from the center of the disk, then in the northern hemisphere it will rest against a point on the celestial sphere with coordinates:
- declination +66, 64°;
- straightascent – 18h00
And this point is located not far from both "bears" in the constellation Draco.
The axis of rotation of the Earth, as we know, is inclined to the axis of the ecliptic (at 23, 44 °), due to which the planet has a change of seasons.
And our "neighbors"
Here's the ecliptic in a nutshell. In astronomy, researchers are also interested in how other bodies in the solar system move. As calculations and observations show, all the main planets revolve around the star in almost the same plane.
The closest planet to the star is Mercury, the angle between its plane of rotation and the ecliptic is as much as 7°.
Of the planets of the outer ring, the orbit of Saturn has the largest angle of inclination (about 2.5 °), but given its enormous distance from the Sun - ten times farther than the Earth, this is excusable for the solar giant.
But the orbits of smaller cosmic bodies: asteroids, dwarf planets and comets deviate from the plane of the ecliptic much more strongly. So, for example, the dwarf planet, the twin of Pluto, Eris has an extremely elongated orbit.
Approaching the Sun at a minimum distance, it flies closer to the star than Pluto, at 39 AU. e. (a. e. - an astronomical unit equal to the distance from the Earth to the Sun - 150 million kilometers), in order to then again retire into the Kuiper belt. Its maximum removal is almost 100 AU. e. So its plane of rotation is inclined to the ecliptic by almost 45°.
