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And the Sun around which something rotates?

The moon revolves around the Earth. The earth revolves around the Sun. A natural question: and the Sun also around something rotates?

The answer to this question astronomers have only in the 20th century, and the answer is YES.

Our Sun is part of a huge star system, which is called the Galaxy (it is also called the milky Way). Our galaxy is in the form of a disk, similar to the two folded edges of the plates. At its center is rounded nucleus of the Galaxy.

Our galaxy - side view
Our Galaxy - side view

If you look at our Galaxy from above, it looks like a spiral, in which the stellar matter is concentrated mainly in its branches, called galactic sleeves. Sleeves are in the plane of the Galaxy disk.

Our galaxy - the view from the top
Our Galaxy is a top view of

Our Galaxy contains more than 100 billion stars. The diameter of the disk of the Galaxy is about 30 thousand parsecs (100,000 light years)[?], and a thickness of about 1000 light years.

Stars inside the disk move in circular paths around the center of the Galaxy, just as the planets in the Solar system revolve around the Sun. The rotation of the Galaxy is clockwise when looking at the Galaxy from its North pole (located in the constellation coma). The rotation speed of the disk is not the same at different distances from the centre: it decreases as the distance from it.

The closer to the center of the Galaxy, the higher density of stars. If we lived on a planet around a star near the nucleus of the Galaxy, the sky would be visible to dozens of stars, the brightness is comparable to the Moon.

However, the Sun is very far from the center of the Galaxy, we can say its edge, at a distance of about 26 thousand light years (8.5 thousand parsecs), near the plane of the galaxy. It is located in the sleeve of Orion, which is connected with the two larger sleeves - inner sleeve of Sagittarius and the outer Sleeve of Perseus.

The position of the Sun in the Galaxy
The position of the Sun in the Galaxy

 

The position of the Sun in the Galaxy
The position of the Sun in the Galaxy, side view

The sun is moving at a speed of about 220 to 250 kilometers per second around the center of the Galaxy and makes a full rotation around its center, according to various estimates, at 220-250 million years. During its existence, the Period of revolution of the Sun, along with the surrounding stars near the center of our star system is called a galactic year. But we must understand that the total period for Galaxy no, because it rotates as a rigid body. The sun during its existence traveled around the Galaxy about 30 times.

The circulation of the Sun around the Galactic centre is oscillatory in nature: every 33 million years it crosses the galactic equator, then rises above its plane to a height of 230 light years away and falls back down to the equator.

Interestingly, the Sun makes a complete revolution around the Galactic centre at exactly the same time as the spiral arm. In the result, the Sun does not intersect the region of active star formation, which often erupt supernova - sources of fatal radiation. That is, it is in the sector of the Galaxy, the most favorable for the emergence and maintenance of life.

By the way...

The most inquisitive howcast probably will not stop there and say, "our Galaxy also rotates around a center?"

And again the answer is Yes.

The milky Way belongs to a group of galaxies, interconnected by gravitational forces, which is called the Local group. In addition to the milky way, it contains the Andromeda galaxy and galaxy Triangle, and about 50 smaller galaxies. The cross-section of the Local group - 1 million parsecs (megaparsecs), or 3 million light years.

The local group of galaxies, in turn, is part of an even larger aggregations of Local Virgo supercluster. Its size is 200 million light years, and its centre is at a distance of 50 million light years from us. Supercluster is rotated around an axis perpendicular to its disk, and resembles in this sense, an ordinary galaxy. The speed of motion of the Local group around the center of surgelati about 400 kilometers per second.

At the end of the 20th century, astronomers have found that the Local supercluster is rushing with the speed of 500-700 kilometers per second in the direction of a huge cluster of galaxies with a strong gravitational force (attraction force), which is called the Great Attractor". Great Attractor, from 'attract' - "to draw, to pull, to capture"). It is approximately 65 million parsecs or 250 million light-years away in the constellation of the Square.

The position of the Solar system in the Supercluster
The hierarchy of movements, with the participation of our planet:
a) the rotation of the Earth around the Sun;
b) rotating with the Sun around the center of our Galaxy;
in motion relative to the center of the Local group of galaxies together with the whole Galaxy under the action of the gravitational attraction of the Andromeda nebula (galaxy M31);
g) moving towards the cluster of galaxies in the constellation Virgo and the movement toward the Great Attractor.

Local supercluster, in turn, is only one of many super-cluster of galaxies in the Universe. Next to our supercluster is located in the constellation Hercules at a distance of 700 million light years, and for about 300 million light-years on the path to him is a total blank, no galaxies, no stars. Thus, the substance in the Universe are not evenly distributed and not chaotically, but in the form of cells, in which faces are concentrated substance, and inside cells - giant empty space"bubbles". Galaxies and their clusters are arranged in order, resembling a honeycomb of unimaginable proportions. The closer to the joints of such cells, the more concentrated the substance. What caused this symmetrical, ordered structure? On this question there is no answer today.

See also:

What is a galaxy?

 


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Total votes: 178

Your comments:

Andrey_Aliev@b
2014-06-08 16:13:48
The earth and any other planet, is making its annual movement in the direction to the Sun and back. The diameter of the annual orbit of the Earth = 5 mlnm, hence the speed of the Earth in its annual orbit of 500 meters per second.
30 km/sec.- this is the daily turnover of the solar sphere at a distance of 150 mlnc from the center of the sphere of the Sun, where is the Earth.
Planet a show at the daily rotation of the solar sphere, in which direction rotates and the Sun and the entire solar sphere.
Its annual motion, being as peripheral object sphere, Constellations, the Sun makes toward the center of the Constellation and back (like Earth in the solar sphere).
Its daily rotation and annual turnover, while in the field of the Galaxy, our Constellation makes toward the center of the Galaxy and back. Also happens in the higher spheres.
About nesting areas spoke about 2400 years ago, the great Greek philosopher Eudoxus.
Light and dogs, flooded all research institutes and academies, 't understand never.
Vlad
2014-06-03 16:29:43
"That scientists know everything. Don't believe. In 100 years there will be other assumptions" ©

Ogromnye facepalm... Here in a simplified form presents the results of long research, based on impeccable evidence And commentary calls this assumption not only believes because he knows nothing about. As you can see, he does not understand, as investigated calls assumptions And I would not be surprised if this man will believe any nonsense that is simply more convincing.

This article has lots of nedoskazannost and a couple of minor problems. There is even no hasty conclusion that you would not believe, according to their own wishes. Yes, after 100 years, scientists will have new data. But only because you have now. But will still be ignorant and illiterate, who do not believe, because I don't want to believe that all of this is subject to scientific explanation.

Juke
2014-05-17 17:18:44
somehow it's a shame that the sun is on the edge(( I WANT IN the CENTER!!!!
Eee
2014-03-21 17:59:17
Well it is direct scientists know everything. Don't believe. In 100 years there will be other assumptions
chip
2014-02-23 00:09:33
I'm shocked.
Shamil
2014-02-04 20:24:08
Very interesting article and poznovatelnaj
Olga
2013-12-08 15:36:54
thank you very much! Very interesting!!)
Galina
2013-11-28 17:09:21
Mysteriously
krutika
2013-11-08 17:12:23
Yes excellent site in bookmarks
Genghis
2013-11-01 06:48:23
Thank you! Excellent article

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