[Spice_discussion] Delta_t from Earth PCK?

[Ernie Wright]

On 06/18/2015 10:30 PM, Nat Bachman wrote:

> It's good we're having this discussion. :)

I agree.  :)

OK, so off the top of my head, the delta_t in earth_#_predict.bpc is 
going to be about 3 seconds too small, moving the eclipse center line 
about a kilometer west at 45N.  That's too small to see in what I'm 
working on at the moment, so I'm going to stop worrying about it.  It's 
still a lot better than IAU_EARTH.

> The best NAIF can do is update the long term predict file to use
> available data up to the current date.

If that were to happen, I'd definitely use it.

Thanks for your help!

- Ernie


-- 
Ernest T. Wright                                ernest.t.wright at nasa.gov
Scientific Visualization Studio                 http://svs.gsfc.nasa.gov
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