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Elegant astronomy for Python
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Milky Way Core Position #271

Closed HenryWede closed 4 years ago

HenryWede commented 5 years ago

Hello, I apologize in advance if this is not the correct place to ask this question. Not sure where else to go...

I would like to calculate the position of the Milky Way core to plan photography trips. It seems that this module does that for the sun and moon, but is there a way to do something for the MW core? For reference, I would like to create something along the lines of this chart/calendar:

https://capturetheatlas.com/wp-content/uploads/2019/01/2019-Milky-Way-Calendar-Moab-Utah.pdf

Thanks for your help.

brandon-rhodes commented 5 years ago

You can ask Skyfield about the position of any sky coordinate by creating a Star object representing that coordinate (Skyfield won't know if there's really a star there in the sky or not). I'm not sure what position they would have used for "Milky Way" though, as it's a loop across the whole sky? You could experiment and see if maybe their calculation is based on the bright part near Scorpius.

ghost commented 5 years ago

https://en.wikipedia.org/wiki/Galactic_coordinate_system may or may not be helpful.

I think skyfield may support galactic coordinates directly, so you can just convert to right ascension and declination.

A good place to ask questions like these is astronomy.stackexchange.com

brandon-rhodes commented 4 years ago

An example script similar to this issue should be added to the documentation written as part of #287.

brandon-rhodes commented 4 years ago

The example script is now officially part of the documentation! Enjoy:

https://rhodesmill.org/skyfield/examples.html#when-is-the-galactic-center-above-the-horizon