<p>The values are more steady for objects close to Ecliptic poles, but in genenral, they change by a few arcseconds every year.</p>

<p>Yes, we lack an absolutely fixed frame of reference.</p>

CC BY-SA 3.0
2014-05-20T02:01:03.463Z
2014-05-20T02:01:03.463Z
Cheeku
<p>I understand that astronomers use right ascension and declination for the position of stars. However both these values strike me as very anthropocentric and, more importantly, unreliable over time as I understand that the Earth wobbles a bit over time so the celestial equator shifts and I guess Sun's rotation around the galaxy and Milky Way's own trajectory should play a role in depreciating the accuracy of those values over time.</p>

<p>So my questions are:</p>

<p>[1] how steady are right ascension and declination values for distant stars over time?</p>

<p>[2] is there a more stable coordinate system or do we lack an absolutely fixed frame of reference?</p>

<coordinate><declination>
how steady over time are right ascension and declination values?
Marcus Junius Brutus
# how steady over time are right ascension and declination values?

(Asked by: username_0 on 2014-05-17)

I understand that astronomers use right ascension and declination for the position of stars. However both these values strike me as very anthropocentric and, more importantly, unreliable over time as I understand that the Earth wobbles a bit over time so the celestial equator shifts and I guess Sun's rotation around the galaxy and Milky Way's own trajectory should play a role in depreciating the accuracy of those values over time.

So my questions are:

[1] how steady are right ascension and declination values for distant stars over time?

[2] is there a more stable coordinate system or do we lack an absolutely fixed frame of reference?

**Tags:** coordinate, declination

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## 1 answers

### Answer by username_1 on 2014-05-20. Score: 3 | Accepted answer

The values are more steady for objects close to Ecliptic poles, but in genenral, they change by a few arcseconds every year.

Yes, we lack an absolutely fixed frame of reference.


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