Welcome to MARX’s documentation!

Current version of marx is 5.5.1.

See Downloading and Installing Marx for installation instructions.


This is the last release of the marx 5.x series. In the next release, we will introduce a better treatment of ACIS grades and sub-pixel positions. Also, we will remove a few tools that convert marx binary results into other formats. Going forward, the only supported tool for this purpose is marx2fits, followed by standard CIAO procedures to make images or extract spectra. We will remove all the IDL tools shipped with marx (e.g. make_image) and marx2dpde and marx2img.


No testing has yet been done on Apple’s new M1 chip since the marx developer has no access to such a machine. If you do, please report your experiences to marx-help@space.mit.edu.

marx is a suite of programs created and maintained by the MIT/CXC/HETG group group and is designed to enable the user to simulate the on-orbit performance of the Chandra X-ray Observatory. marx provides a detailed ray-trace simulation of how Chandra responds to a variety of astrophysical sources and can generate standard FITS event files and images as output. It contains detailed models for Chandra’s High Resolution Mirror Assembly (HRMA), the HETG and LETG gratings, and all the focal plane detectors.

If you publish any work that made use of marx, please cite the paper Raytracing with MARX: x-ray observatory design, calibration, and support (Davis et al. 2012, SPIE 8443, 84431A).

Indices and tables