If you're working with astronomical data in Python, this is the standard library you reach for. It handles the everyday astronomy tasks: transforming between coordinate systems (ICRS to Galactic to AltAz), converting units with proper dimensional analysis, reading and writing FITS files, and doing cosmological calculations with models like Planck18. The time handling is precise enough for professional astronomy work, supporting different time scales and formats. It also includes table operations for catalog work and WCS transformations for mapping between pixel and sky coordinates. Honestly, it's comprehensive enough that you'll spend time learning which submodule does what, but that beats reinventing coordinate math or FITS parsers yourself.
npx skills add https://github.com/davila7/claude-code-templates --skill astropy