Comment 6 for bug 1652762

I would display the DeltaT compensated for the n.dot of the ephemeris (and
not the uncompensated DeltaT). Only when compensate it is comparing like
(seconds) with like (seconds).

On 29 December 2016 at 19:27, gzotti <email address hidden> wrote:

> Hmm, I think there is a misunderstanding what should be displayed here:
>
> We have 2 algorithms for the planets, ELP2000 (with nDot=-23.8946) or
> DE43x (-25.8). If we select some DeltaT algorithm on the Navigation tab
> of the config panel, then some (usually different) nDot (which belongs
> to the DeltaT algorithm) is activated. This is the value that should be
> displayed at this location. I changed this in revision 9031, together
> with (hopefully) a small optimisation.
>
> It is interesting to observe: Changing to DE431 around -2000 now keeps
> the moon in (practically) the same position for equal UT, and DeltaT is
> different by about 40 minutes. This seems to show the positional
> closeness of DE431 and VSOP/ELP when the nDot compensation is working,
> right? (I mean, the numerical value of DeltaT is secondary. It is rather
> LunarPosition(UT) that counts here. Must still compare positions with
> old eclipse reports...)
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1652762
>
> Title:
> n.dot not changing
>
> Status in Stellarium:
> Fix Committed
>
> Bug description:
> Using 0.15.1.
>
> If I change between VSOP and DE431, and with time 'stopped' the
> displayed n.dot value is not changed (when hovering over the time).
> If I let the time 'run' the n.dot is changed when switching between VSOP
> and DE431.
>
> All the best,
>
>
> Victor
>
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