There are a number of options for installing the astropy package on MacOS X.

The Anaconda Python Distribution is one of the most common ways to install both Python and astropy. Once you have Anaconda installed, update to the latest version of astropy:

conda update astropy

Astropy can also be installed using the MacPorts or Fink package managers. It is also included with Enthought Canopy and AstroConda. You can also install the latest version of Astropy using pip.

There are a number of options for installing the astropy package on Linux. Astropy can be installed on some Linux distributions using the built-in package manager (apt-get, yum, etc.), and is also included by default in the Anaconda Python Distribution (see here for instructions on updating to the latest Astropy version), Enthought Canopy, and AstroConda, which provide an easy way to get set up with a scientific Python distribution.

The package managers, Anaconda, and Canopy may not always include the latest version - in that case you can always install the latest version of Astropy using pip or by downloading the source code and installing it manually - see the Source tab above for more details.

There are a number of options for installing the astropy package on Windows. Astropy is included by default in the Anaconda Python Distribution and Enthought Canopy, both of which provide an easy way to get set up with a scientific Python distribution.

However, Anaconda and Canopy may not always include the latest version of Astropy, so if you need to install the latest version, you can either use the binary installers available on PyPI (usually made available a few days after each release) or you can install Astropy from source - see the Source tab above for more details.

To install Astropy from source, you can either use

pip install astropy

Alternatively, you can download a tarball for the latest release of astropy from PyPI, then expand the tarfile and run:

python setup.py install

to build and install the package. For more on installing from source code, see the relevant part of the documentation.

The latest developer code is available on GitHub. If you have git installed you can get the latest version with:

git clone https://github.com/astropy/astropy.git

If you don't have git installed, you can instead download a zip file of the latest development version.

Once you have the latest source code, you can build and install it with:

python setup.py install

For more on installing from source code, see the relevant part of the documentation.