Ephemerides

[astrojuanlu]

Look into https://github.com/brandon-rhodes/python-jplephem

[astrojuanlu]

Or perhaps the newly released https://github.com/brandon-rhodes/python-skyfield!

Inspiration: http://nbviewer.ipython.org/github/james-prior/astronomy-notebooks/blob/jep-black-inline-images-issue/Interactive-3D-Solar-System.ipynb

[astrojuanlu]

It would be nice to modify the mass parameters of the planets when loading an ephemeris, see brandon-rhodes/python-jplephem#9.

[astrojuanlu]

Other than that, this is how the ephemeris can be loaded using jplephem and astropy:

>>> from datetime import datetime
>>> from astropy import time
>>> from jplephem.spk import SPK
>>> kernel = SPK.open('de421.bsp')
>>> t = time.Time(datetime.today())
>>> t.jd
2457117.0397053314
>>> kernel[0, 4].compute(t.jd)
array([  1.54722791e+08,   1.42346197e+08,   6.11033174e+07])
>>> kernel[0, 4].compute(t.jd1, t.jd2)
array([  1.54722791e+08,   1.42346197e+08,   6.11033174e+07])

jplephem.spk is very low level so perhaps I will have to build a slightly higher level API.

[astrojuanlu]

Ideas to handle ephemeris data: https://github.com/jaberg/skdata/wiki/Managing-Data

[astrojuanlu]

Another idea: spacepy copies required files on import: http://sourceforge.net/p/spacepy/code/ci/master/tree/spacepy/__init__.py

May I provide some kind of script instead?

[astrojuanlu]

In case I go the script way, now that I have setuptools I can use entry points. See also conda-build: http://conda.pydata.org/docs/build.html

[astrojuanlu]

Closed on 2404de7 🎉