Skip to main content

Introduction to STIPS for Roman

The STIPS (Space Telescope Image Product Simulator) software produces simulated imaging data for complex wide-area astronomical scenes, based on user inputs, instrument models and library catalogs for a range of stellar and/or galactic populations. It was originally developed for the James Webb Space Telescope (JWST) mission, and has been extended to include Nancy Grace Roman Space Telescope functionality as well. The current Roman Space Telescope version produces images covering a single detector in the Wide Field Instrument (WFI) field of view. STIPS includes current information about the telescope sensitivity, spectral elements, and detector properties. It uses the PSF model generated by WebbPSF1, and it calls the appropriate Pandeia modules to compute instrumental throughput and count rates.

A new version of STIPS (v2.0) was released in September 2022. The release includes the implementation of empirical PSFs to improve the astrometry of the sources, as well as several bug fixes. STIPS is available on GitHub as a Python module, and also via PyPI.

Pseudocolor image of the central region of a globular cluster
Pseudocolor image of the central region of a globular cluster viewed in the F087, F129, and F184 filters of the Roman Wide Field Instrument (WFI), as simulated using STIPS.



At the heart of STIPS is a generator that allows varying degrees of user control. STIPS can generate a randomized set of stars or idealized galaxies based on very concise user specifications, or it can generate point or extended sources based on a detailed input catalog. In addition, an existing image can be used as background.

How STIPS works


STIPS can be run by users locally by cloning the GitHub repository or installing the PyPI package. STIPS Documentation is being maintained on Read the Docs. 

What to know about STIPS


Credits, Acknowledgements, and Feedback

STIPS is currently managed and developed by the Roman Telescope Branch in the Instrument Division at STScI. Credit for initial development of the software go to Brian York and Robel Geda, with guidance and contributions from Klaus Pontoppidan, Jason Kalirai, Pey Lian Lim, and Stefano Casertano. STIPS makes use of open source astronomical software developed by Justin Bird, Ahmed Fasih, and Adam Ginsburg.

Users are encouraged to address questions, suggestions, and bug reports to with "STIPS-Roman question" in the subject line. The message will then be directed to the appropriate members of the STIPS-Roman team at STScI. In addition, bug reports may be filed against the STIPS GitHub module.

1 The Roman PSF module in WebbPSF is accessed through the following: 'from WebbPSF import roman', as of Webb PSF v1.0.0.


Nancy Grace Roman Space Telescope insignia

The NASA Nancy Grace Roman Space Telescope is managed by NASA/GSFC with participation of STScI, Caltech/IPAC, and NASA/JPL.

Contact the Roman Team