Why is the star Polaris perfectly still? If the earth is spinning while rotating around the sun, and even the sun is moving,?
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Why is the star Polaris perfectly still? If the earth is spinning while rotating around the sun, and even the sun is moving,?

[From: ] [author: ] [Date: 17-04-24] [Hit: ]
tonight, then come back in a thousand years, you would notice (in a thousand years) that it traces a larger circle.Thats because the projection of the axis will have moved away from Polaris.-quantumclaustrophobe say: Its not truly still.But,......
Raymond say: Polaris is really almost a full degree off the projection of Earth's axis onto the celestial sphere.
Therefore, Polaris would appear to trace a tiny circle around the "celestial pole".

1 degree is close enough for most people to use Polaris to find due North.
Navigators have to apply the correction.

Compared to the distance between us and Polaris, the distance Earth travels in a few centuries is nothing.

However, the Earth's rotation axis "wobbles" so that it will slowly move away from Polaris. If you were able to look at Polaris for an entire night, tonight, then come back in a thousand years, you would notice (in a thousand years) that it traces a larger circle. That's because the projection of the axis will have moved away from Polaris.
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quantumclaustrophobe say: It's not truly still. But, our distance from Polaris - 435 light years - or 2.55 x 10^15 miles - is so distant, that it's movement is not discernable to the naked eye.
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oikoσ say: It isn't still. It just appears to be moving more slowly from Earth's perspective.
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moondog say: its not, it just appears that way because you cant live 23,400 yres and witness the circular motion of star about our polar axis.it completes one revolution every 23,000 years over so...
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Al say: OMG. Because the north axis around which the earth rotates is pointing nearly directly at Polaris. It wasn't always that way however, because the earth's axis precesses in a circle every 40000 years or so.
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CarolOklaNola say: Polaris actually is NOT stationary. it makes a very small circle around the north celestial pole every 24 hours because it is offset by about 45 minutes.

"..But the North Star does move. If you took its picture, you’d find that it makes its own little circle around the exact point of the north celestial pole every day. That’s because the North Star is really offset a little – by about three-quarters of a degree – from celestial north.

Where does this movement – or in Polaris’ case, lack of movement – come from? Earth spins under the sky once a day. Earth’s spin causes the sun in the daytime – and the stars at night – to rise in the east and set in the west. But the North Star is a special case. Because it lies almost exactly above Earth’s northern axis, it’s like the hub of a wheel. It doesn’t rise or set. Instead, it appears to stay put in the northern sky...."

http://earthsky.org/astronomy-essentials...

The north star DOES move, 12,00 years ago Vega was the north star and Vega will be the north star again in another 12,000 years because of the precession Earth's rotational axis. Dubhe in Draco was the north star when for the Egyptians 500 years ago. NOT Polaris.

https://en.wikipedia.org/wiki/Axial_prec...
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