Thnx to all, for the answer. I had a good time discussing and clearing my doubt.
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Each rotation around the sun has a small effect on stats, it is used to measure distance, it is called [https://en.wikipedia.org/wiki/Stellar_parallax](https://en.wikipedia.org/wiki/Stellar_parallax)
The effect is tiny because earth orbit around the sun is small compared to the distance to the start. The closes star Alpha Centauri is 138,000 times the orbital diameter it has a parallax of 750mas. 1 mas =1 Milliarcsecond = 1/3600000=0.00000027 degrees so 750 mas =0.0002 degrees. You need to take images and compare it to stars faster away to see it.
The sun orbits the galactic core but so do the other star. We are around 26,000 lightyears from the galactic center and an orbit take 230 million years. So we have moved less then1/125000 of a revolution in 200 years. One revolution ago was before dinosaurs emerged on earth, earth have obit less than 11 times since it was founded.
Orbital time depend on the distance so object close to the sun will orbit at quite a similar speed. All start you can see with you naked eye are with 4,000 light years.
If you look at the 300 brightest start the median is 185 light year with the distribution below
* <10 light years = 2 stars (Sirius and Rigel)
* 10-100 light years = 79 stars
* 101-1000 light years = 200 stars
* 1000 light years = 19 stars
The result is a consolation change but quite slowly. It is called https://en.wikipedia.org/wiki/Proper_motion and is measured. most start motion is less the 10 mas per year so it is not a lot.
Barnard’s Star moves faster at 10,000 mas per year it is 6 light years from us but it is to dim to see with your naked eye.
61 Cygni A is the faster visible at 5281 mas per year but in 2000 it is still just 3 degrees. It is not a bright start but visible.
The brightest star Sirius moves at 461mas/year is 0.25 degrees in 2000 years
So constellation does change but it is quite slow.
that’s a bit like asking “why hasn’t the season changed in the last ten minutes even though the earth has been orbiting the sun for that whole time?”
the sheer scale of the galaxy is incomprehensibly large. 5000 years is nothing on that scale, the stars have all barely had a chance to move
All the stars that we can see in the sky are relatively close by, within about a hundred light years (the galaxy is a hundred _thousand_ light years across). This local group of stars travels around the center of the galaxy at about the same speed, so the speed of the Sun relative to the nearby stars is low, compared with the distance to these stars. Also distances in space are very, very large. Unimaginably large. You literally have no idea how big interstellar space is.
Distances in the universe are incredibly huge, so that even the great speed at wich stars move around the galaxy is extremely slow in comparision.
One “galactic year” is 230 million earth years. The last time the sun was in this position was before the first dinosaurs.
Those 5000 years humans have mapped stars are just the blink of an eye on that timescale. Stars changed positions, but not noticable for us.
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