Astronomy and astrophysics core library
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The Astropy Project ( is a community effort to develop a single core package for Astronomy in Python and foster interoperability between Python astronomy packages. This repository contains the core package which is intended to contain much of the core functionality and some common tools needed for performing astronomy and astrophysics with Python.

Releases are registered on PyPI, and development is occurring at the project's GitHub page.

For installation instructions, see the online documentation or docs/install.rst in this source distribution.

Contributing Code, Documentation, or Feedback

The Astropy Project is made both by and for its users, so we welcome and encourage contributions of many kinds. Our goal is to keep this a positive, inclusive, successful, and growing community by abiding with the Astropy Community Code of Conduct.

More detailed information on contributing to the project or submitting feedback can be found on the contributions page. A summary of contribution guidelines can also be used as a quick reference when you are ready to start writing or validating code for submission.

Supporting the Project

Powered by NumFOCUS

The Astropy Project is sponsored by NumFOCUS, a 501(c)(3) nonprofit in the United States. You can donate to the project by using the link above, and this donation will support our mission to promote sustainable, high-level code base for the astronomy community, open code development, educational materials, and reproducible scientific research.


Astropy is licensed under a 3-clause BSD style license - see the LICENSE.rst file.

If you locally cloned this repo before 7 Apr 2021

The primary branch for this repo has been transitioned from master to main. If you have a local clone of this repository and want to keep your local branch in sync with this repo, you'll need to do the following in your local clone from your terminal:

git fetch --all --prune
# you can stop here if you don't use your local "master"/"main" branch
git branch -m master main
git branch -u origin/main main

If you are using a GUI to manage your repos you'll have to find the equivalent commands as it's different for different programs. Alternatively, you can just delete your local clone and re-clone!