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, formerly known as the Wide Field Infrared Survey Telescope (WFIRST), 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 the most current information about the telescope sensitivity, spectral elements, and detector properties. It uses the PSF model generated by WebbPSF-WFIRST, and it calls the appropriate Pandeia modules to compute instrumental throughput and count rates.

STIPS is available on GitHub as a Python module, and also via a web interface that provides a straightforward way of creating observation simulations. To obtain access to the Roman data files or the STScI STIPS-WFIRST webserver, please request access as described in the Using STIPS section below.

Pseudocolor image of the central region of a globular cluster
Pseudocolor image of the central region of a globular cluster viewed in the Z087, J129, and F184 filters of the Roman Wide Field Instrument (WFI), as simulated using STIPS.



At the heart of STIPS is a multi-faceted scene generation 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.


The STIPS central module and web server interface is available on GitHub. STIPS can be run by users locally, through use of GitHub or via STScI's simulation website. Since STIPS is presently in beta release, access to the STScI web interface is restricted to people connected to the Roman Space Telescope Project and Science Teams. Access is offered upon request.

Users are authenticated using their Mikulski Archive for Space Telescope (MAST) account. If you do not yet have such an account, please register. Then go to the STScI HST Help Desk and send a message with your name, institutional affiliation, the MAST account name, and a description of your connection to the Roman Project or Science Teams. Put “Request for STIPS access” in the subject line to ensure your request is routed to the appropriate person. You will receive instructions from the Help Desk. Once your account is authorized, you may visit the STIPS simulation website to run STIPS simulations.

A detailed description of the format of input source catalogs is available. Much of the remaining STIPS documentation has yet to be written. Some documentation can be accessed as follows:


Credits, Acknowledgements, and Feedback

STIPS is developed by Brian York, 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 the STScI HST Help Desk. The message will then be directed to the appropriate members of the STIPS-WFIRST team at STScI. In addition, bug reports may be filed against the STIPS GitHub module.


Contact Information



Please contact with "STIPS-WFIRST Question" in the subject line.

Contact the Roman Team