Why do all the stars appear to move around one central star and why is Polaris different from other stars in the sky?
As a planet rotates, no matter HOW it rotates, there must be an axis running through its center that it rotates around. That axis can point in any direction (and for different planets, DOES rotate in different directions: See "Seasons on the Other Planets" at https://cseligman.com/text/sky/otherseasons.htm ), but whatever direction that is for a given planet, all stars near that (and the opposite) direction will appear to rotate around a point in the sky in that direction (See Polar Animation at https://cseligman.com/text/sky/polaranimation.htm ). In the case of the Earth, because of tidal effects on its rotation caused by the Sun and Moon, that direction changes over time, moving in a circle about 23 1/2 degrees in radius once every 26 thousand years or so. On my page about Ursa Minor: The Little Bear (see https://cseligman.com/text/atlas/ursaminor.htm ) there are two historical maps which show a picture of the "bear" and a large number of concentric circles nd a vertical line passing through the tail of the bear. The TOP of that line is the center of the "precession" of the Earth's axis of rotation over a period of 26 thousand years, and in the second picture some of the stars are labeled with their names, an the dates when the axis of the Earth's rotation happened to pass close to those stars. 5000 years ago the Pole pointed almost exactly at the star Thuban, and all the stars seemed to rotate around Thuban. But in the 5000 years since then, the axis has slowly moved along the circle, so that now it points nearly at Polaris (5000 years ago that star wasn't called Polaris, because it wasn't near the axis of rotation, and stars didn't seem to rotate around it; but in the last 1000 years of so the axis of rotation has gradually gotten closer and closer to Polaris (though it will never point as exactly at Polaris as it once pointed exactly at Thuban), so the star's name was changed to Polaris to reflect the fact that it is now the closest reasonably bright star to the Pole in the sky. In other words, Polaris is a big deal NOW because it happens to be close to the current location of the axis of rotation of the Earth extended into the sky; but it was never that close to the Pole in the past, and will never be that close in the future, either, because by the time the circle of precession gets back to where Polaris is now (26 thousand years from now), Polaris will have moved a little relative to its current position, and though in 26 thousand years it will be the closest star to the Pole again, it won't be quite as close as now.
In other words, ANY place in the sky could be near a given planet's axis of rotation, and whether there is a reasonably bright star close to that place at any given time is merely a matter of chance. So there is nothing special about Polaris except for a chance agreement between the current position of the Pole in the sky and the position of that star.
Note: I think I've stomped out all the typographical errors, but it's the middle of the night here, so I may have missed one or two; if so, I apologize for any mistakes.
Polaris, the North Star, appears stationary in the sky because it is positioned close to the line of Earth's axis projected into space. As such, it is the only bright star whose position relative to a rotating Earth does not change. All other stars appear to move opposite to the Earth's rotation beneath them. Polaris is the star in the center of the star field; it shows essentially no movement. Earth's axis points almost directly to Polaris, so this star is observed to show the least movement. The other stars appear to trace arcs of movement because of Earth's spin on its axis. These apparent star tracks are in fact not due to the stars moving, but to the rotational motion of the Earth. As the Earth rotates with an axis that is pointed in the direction of the North Star, stars appear to move from east to west in the sky. If you watch the night sky for a few hours, you will see that the stars appear to rotate about a fixed point in the sky (which happens to be near the pole star, Polaris). This motion is due to the Earth's rotation. Polaris is located quite close to the point in the sky where the north rotational axis points a spot called the north celestial pole. As our planet rotates through the night, the stars around the pole appear to rotate around the sky. Over the hours, these stars each sweep out a circle around the celestial pole. The stars in our galaxy are all orbiting in a nearly circular path around the center of the galaxy. They do this because the immense combined mass of the galaxy, most if it near the center, creates immense gravity that pulls all the stars in our galaxy into circular orbits. Some stars travel a great distance over the course of the night. Polaris is different. Because it's so close to the celestial pole, it traces out a very small circle over 24 hours. So Polaris always stays in roughly the same place in the sky, and therefore it's a reliable way to find the direction of north. The North Star or Pole Star aka Polaris is famous for holding nearly still in our sky while the entire northern sky moves around it. That's because it's located very close to the north celestial pole, the point around which the entire northern sky turns.The pole star is in the center of a star field. It does not appear to move because the pole star is aligned with the earth's axis. Due to the rotation of the Earth about its axis, the other stars appear to trace arcs of movement. So now you can see why Polaris will not always be aligned with the north spin axis of the Earth - because that axis is slowly changing the direction in which it points! Right now, the Earth's rotation axis happens to be pointing almost exactly at Polaris.
The night sky movement you see isn't actually the stars circling another star, but rather the Earth spinning on its axis. As Earth rotates from west to east, the whole sky appears to rotate in the opposite direction, east to west. This is why stars seem to rise in the east and set in the west.
Polaris, also known as the North Star, is different because it sits very close to Earth's rotational axis. As Earth spins, Polaris stays nearly fixed in one spot, while other stars trace out circular paths around it. This makes Polaris a handy reference point for navigation in the Northern Hemisphere.
The night sky movement you see isn't actually the stars circling another star, but rather the Earth spinning on its axis. As Earth rotates from west to east, the whole sky appears to rotate in the opposite direction, east to west. This is why stars seem to rise in the east and set in the west.
Polaris, also known as the North Star, is different because it sits very close to Earth's rotational axis. As Earth spins, Polaris stays nearly fixed in one spot, while other stars trace out circular paths around it. This makes Polaris a handy reference point for navigation in the Northern Hemisphere.
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