# Tag Info

0

The corrections are so small that simply changing the signs in the formulas may give a sufficiently accurate result. In any case the formulas you quote are already a first order approximation, whereas TPOINT implements the NPAE, CA, AN and AW terms using rigorous vector expressions - for example AN and AW are part of a 3D rotation.

2

I think there's been a little bit of confusion, both about the passage in Wikipedia and the phrasing in the question. Your post asks two distinct questions: Why an isolated pulsar's rotation slows down over time, and why this slowdown eventually leads to the end of radio emission. The gist of the answer to the first - rotational kinetic energy is transferred ...

4

The Milky Way takes 225-250 Million years for one rotation (at Sol's radius). Humanity has been here, and looking up, for, at most (and to make the numbers easier) 10,000 years. 10,000 / 250,000,000 = 0.00004 We (humanity) have been seeing stars for 4 hundred-thousandths of a revolution, or 0.0144 degrees of rotation. The constellations change, we just haven'...

20

Here's an animation I found that gives you an idea of the movements and timescales involved: It depicts the estimated movement of the Orion Constellation from 3 million years in the past to 3 million years in the future.

51

Yes, the shape of the constellation does and will change over time. All the stars have their own peculiar velocities and have some random motion which over time will ruin all the constellations. However, Even though the stars are moving at rapid speeds, to us, in our sky, due to their enormous distance from us, they appear to move extremely slowly and the ...

3

This appears to me as just the consequence of having an altazimuthally mounted “camera” (the simulation). Objects are tilted towards the left when they rise, towards the right when they. set. You can verify that easily by looking at the Moon when it rises and sets from your own place. This is due to the horizon being “tilted” with respect to the Earth’s ...

4

No special name. The problem that I see here is that the distance will vary over the year. At the moment of solstice, you can easily find the distance by basic trigonometry: If the center of the Earth is C, then $AC/AB = \tan(23.5^\circ)$ so $AB = 6370/\tan(23.5^\circ)=13000\, \mathrm{km}$ At any other time the distance will be different, and at the ...

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