WARNING: The default main branch is the development version of MESA and is not guaranteed to function correctly. If you are using MESA, you should use an official release version.

MESA is a powerful and versatile open-source software suite built to allow users to run experiments in stellar evolution. Stellar evolution calculations (i.e., stellar evolution tracks and detailed information about the evolution of internal and global properties) are a basic tool that enable a broad range of research in astrophysics. Areas that critically depend on high-fidelity and modern stellar evolution include asteroseismology, nuclear astrophysics, stellar populations, chemical evolution and population synthesis, astrobiology, binary stars, variable stars, supernovae, novae, compact objects, tidal disruption events, stellar hydrodynamics, and stellar activity.

New observational capabilities are emerging in these fields that place a high demand on exploration of stellar dependencies on mass, metallicity and age. So, even though one dimensional stellar evolution is a mature discipline, we continue to ask new questions of stars. Some important aspects of stars are truly three-dimensional, such as convection, rotation, and magnetism. These aspects remain in the realm of research frontiers with evolving understanding and insights, quite often profound. However, much remains to be gained scientifically (and pedagogically) by accurate one-dimensional calculations, and this is the focus of MESA.

• Code repository on GitHub (this page).
• Documentation for up-to-date information about installing and running MESA.
• MESA Marketplace for resources for published papers using MESA.
• MESA Zenodo Community for downloading official release versions, SDKs, and MESA project inlists.
• MESA Test Hub to view results of regression testing (for Developers).
• mesa_test tool to run the test suite and upload results to the MESA Test Hub (for Developers).