instructions for downloading jplephem subset of .bsp file fails

the problem doesn’t appear to be inside of skyfield per se, but I’m hoping you can give insight. In https://rhodesmill.org/skyfield/planets.html the instructions have the example:

$ python -m jplephem excerpt 2018/1/1 2018/1/15 $u jup_excerpt.bsp```, however:

1. jup310.bsp is no longer active, but looking at the JPL site, I found the up-to-date (full) files.
2. Trying sat427 (or any of them), e.g.:

```$ python -m jplephem excerpt 2021/1/1 2030/1/1 https://naif.jpl.nasa.gov/pub/naif/generic_kernels/spk/satellites/sat427.bsp sat_excerpt.bsp```

always throws an error:

```AttributeError: 'RemoteFile' object has no attribute 'close'```
and doing some pecking, that's true --- the class Remotefile does not have a .close() method.

I've tried to get around this (commenting out the line, etc.) but that just throws different errors.

I've tried doing a GS on this error, but came up empty-handed - so I can't tell if somehow my local install has an issue, of what.

Can you try the above command and see if you replicate the problem?

(Or, jup365, mar097, nep095, or ura111 - same issue.)

[brandon-rhodes]

Thanks for pointing that out! I have just released a new version of jplephem that should fix the problem. Try:

pip install -U jplephem

— and see whether that fixes the subcommand. Hopefully it will now work!

[brandon-rhodes]

Wonderful, I’m glad that Skyfield is helping you eliminate code that you would otherwise have to maintain yourself! Thanks for sharing your positive experience, it’s encouraging.

If you’d like to share one of the weird phase angle numbers that Skyfield is returning for a planet, I’d be interested in seeing it to determine whether the phase-angle routine needs to be tweaked to work correctly with planets.