The universe is striking in its size and speed. All objects (stars, planets, asteroids, stardust) in it are in constant motion. Many of them have similar trajectories, since they are subject to the same laws. The movement of the solar system in the galaxy has its own characteristics, which may seem unusual at first glance, although it obeys the same laws as other objects in space.
A brief history of astronomy
Previously, people thought that the Earth was flat and covered with a crystal cap, and the stars, the Sun and the Moon were attached to it. In ancient Greece, thanks to the work of Ptolemy and Aristotle, it was believed that the Earth has the shape of a ball, and all other objects move around it. But already in the XVII century, for the first time, doubts were expressed that the Earth is the center of the world. Copernicus and Galileo, observing the movement of the planets, came to the conclusion that the Earth rotates with other planets around the Sun.
Modern scientists have gone even further and determined that the Sun is not the center and, in turn, revolves around the center of the Milky Way galaxy. But this turned out to be not entirely accurate. Near-Earth orbiting telescopes have shown that our Galaxy is not the only one. In space there are billions of galaxies and clusters of stars, clouds of cosmic dust, and the Milky Way galaxy is also moving relative to them.
Light
The sun is the main driving force behind the movement of the solar system in the galaxy. It moves along an elliptical, almost perfectly circular circle, and pulls the planets and asteroids that are part of the system. The sun rotates not only around the center of the Milky Way galaxy, but also around its own axis. Its axis is shifted to the side by 67.5 degrees. Since it (with such a tilt) practically lies on its side, it seems from the side that the planets that make up the solar system rotate in a vertical, and not in an inclined plane. The sun rotates counterclockwise around the center of the galaxy.
It also moves in the vertical direction, periodically (once every 30 million years), then falling, then rising relative to the central point. Perhaps this trajectory of the solar system in the galaxy is due to the fact that the core of the Milky Way galaxy rotates around its own axis like a top - periodically leaning in one direction or the other. The sun only repeats these movements, since according to the laws of physics it should move strictly along the equator line of the central body of the Galaxy, in which, according to scientists, there is a giant black hole. But it is quite possible that such a trajectory is a consequence of the influence of other large objects.
The speed of the solar system in the galaxy is equal to the speed of the sun - about 250 km / s. It makes a complete revolution around the center in 13.5 million years. In the entire history of the existence of the Milky Way galaxy, the Sun has made three full turns.
Laws of motion
When determining the speed of the solar system around the center of the galaxy and the planets that make up this system, one should take into account the fact that Newton’s laws, in particular the law of attraction or gravity, act inside the solar system. But in determining the trajectory and velocity of the planets around the center of the galaxy, the Einstein law of relativity also applies. Therefore, the speed of the solar system is equal to the speed of revolution of the sun, since about 98% of the total mass of the system is in it.
His movement in the Galaxy obeys Kepler’s second law. In the same way, the planets of the solar system obey this law. According to him, they all move in one plane around the center of the sun.
To the center or from it?
In addition to all the stars and planets moving around the center of the galaxy, they also move in other directions. Scientists have long determined that the Milky Way galaxy is expanding, but it happens more slowly than it should be. This discrepancy was revealed by computer simulation. The discrepancy for a long time caused bewilderment among astronomers, until the existence of black matter was proved, which does not allow the Milky Way galaxy to disintegrate. But the movement away from the center continues. That is, the solar system moves not only in a circular orbit, but also moves in the opposite direction from the center.
Motion in infinite space
Our Galaxy is also moving in space. Scientists have found that it is moving in the direction of the Andromeda nebula and will collide with it in a few billion years. At the same time, the movement of the Solar system in the Galaxy occurs in the same direction, since it is part of the Milky Way, at a speed of 552 km / s. Moreover, its speed of movement to the Andromeda nebula is much higher than the speed of revolution around the center of the Galaxy.
Why the solar system does not decay
Outer space is not a void. The entire space around stars and planets is filled with cosmic dust or dark matter that surrounds all galaxies. Large clusters of cosmic dust are called clouds and nebulae. Often clouds of cosmic dust surround large objects - stars and planets.
The solar system is surrounded by such clouds. They create the effect of an elastic body, which gives it more strength. Another factor that does not allow the solar system to decay is the strong gravitational interaction between the sun and the planets, as well as the large distance to the stars closest to it. So, the closest star to the Sun, Sirius, is located at a distance of about 10 million light-years. To make it clear how far this is, it is enough to compare the distance from the star to the planets that make up the solar system. For example, the distance from it to the Earth is 8.6 light minutes. Therefore, the interaction of the Sun and other objects inside the solar system is much stronger than other stars.
How planets move in the universe
Planets move in the solar system in two directions: around the sun and with it around the center of the galaxy. All objects that make up this system move in two planes: along the equator line and around the center of the Milky Way, repeating all the movements of the luminary, including those that occur in the vertical plane. At the same time, they move at an angle of 60 degrees relative to the center of the galaxy. If you look at how the planets and asteroids of the solar system move, then their movement is spiral. Planets move behind and around the Sun. Every 30 million years, a spiral from planets and asteroids rises up with the luminary and also smoothly descends.
The movement of planets inside the solar system
In order for the picture of the movement of the system in the Galaxy to take on a complete form, one should also consider at what speed and in what orbit the planets move around the Sun. All planets move counterclockwise, also they rotate around their own axis counterclockwise, with the exception of Venus. Many have multiple satellites and rings. The farther the planet is from the Sun, the more elongated orbit it has. For example, the dwarf planet Pluto has such an elongated orbit that when passing perihelion passes closer to it than Uranus. Planets have the following speeds around the sun:
- Mercury - 47.36 km / s;
- Venus - 35.02 km / s;
- Earth - 29.02 km / s;
- Mars - 24.13 km / s;
- Jupiter - 13.07 km / s;
- Saturn - 9.69 km / s;
- Uranus - 6.81 km / s;
- Neptune - 5.43 km / s.
The regularity is obvious: the farther the planet is from the star, the slower its speed and longer the path. Based on this, the spiral of motion of the solar system has the highest speed near the center and the lowest on the outskirts. Until 2006, Pluto was considered the extreme planet (speed of 4.67 km / s), but with a change in classification it was assigned to the category of large asteroids - dwarf planets.
The planets move unevenly along elongated orbits. The speed of their movement depends on at what point this or that planet is. So, at the point of perihelion, the linear speed of movement is higher than in aphelion. Perihelion is the farthest point on the elliptical trajectory of the planet from the Sun, aphelion is the closest to it. Therefore, the speed may vary slightly.
Conclusion
Earth is one of billions of grains of sand wandering in infinite space. But its movement is not chaotic, it is subject to certain laws of motion of the solar system. The main forces that influence its movement are gravity. The forces of two objects act on it - the Sun as the nearest star and the center of the Galaxy, since the solar system into which the planet enters revolves around it. If we compare the speed of its motion in the Universe, then it, along with the other stars and planets, moves in the direction of the Andromeda nebula at a speed of 552 km / s.