Important Announcements About This Release

STK 13.1 Announcements

  • Python is now a supported language for Astrogator calculation object plugin scripts. As a result, JScript, VBScript, and CustomFunction calculation object plugin scripts have been deprecated.
  • STK now includes version 2025.1.0 of the Intel MKL library. This MKL release includes numerous security fixes as well as optimized matrix algorithms for new CPU microarchitecture types. Since ODTK uses MKL to perform large matrix operations you may notice slightly different results (on the level of last digit numerical noise) from established regression tests.
  • The TIREM RF propagation library has been updated to version 6.30.
  • Stars defined using angle and rates measured using the J2000 frame are now modeled as moving along a line in ICRF space; they are no longer modeled as moving along a line in J2000 space. Because the J2000 frame slowly drifts and oscillates away from ICRF, lines modeled in the J2000 spaces are not lines in ICRF space and represent a poorer approximation to the motion of the star than linear motion in ICRF.
  • The STK installer will warn you if you do not have the required Media Feature Pack installed when installing on Windows 10 or 11.
  • Analyzer features have been deprecated following the release of STK 13.0. Access to these features and many more are now available through the STK plugin available with ModelCenter.

STK 13.0.1 Announcements

The install no longer sets the default to allow Connect through a socket. Consequently, the STK application no longer starts listening to Connect commands on a socket by default. If that capability is required, you can turn it on explicitly by selecting the Allow Connect checkbox on the Edit/Preferences/Connect menu, whether through the UI or other API options.

STK 13.0 Announcements

  • "AGI SEDS/Geospatial Content Server" has been replaced with the "Ansys Geospatial Data Cloud," a self-hosted Cesium ion instance maintained by AGI. Custom SEDS and Geospatial Content Servers are deprecated but still supported in the STK application.
  • For STK application version 13, OpenGL 4.5 is required to render fully the STK application. For systems that do not meet the hardware requirements for OpenGL 4.5, the STK application offers a software rendering option that you can enable in the Edit menu under Preferences > General > Graphics.
  • Support for COLLADA 3D model format has been removed from the STK application. COLLADA is an old format that is not properly supported by current 3D modeling tools, and the specification is no longer being maintained. The STK application supports the widely adopted glTF format for 3D models. You should convert 3D models to glTF format for compatibility.
  • MATLAB connectors were updated to v1.0.24 for MATLAB 2025a. For more information, see our MATLAB page.
  • The HTML Viewer has been removed. Use the STK application's Web Browser when using HTML tools and sites. A new Connect command called OpenWebBrowser is available to open the new Integrated Web Browser. You can learn more about this command in the Connect help.
  • For STK application version 13, the Excel Add-in has been removed.
  • The STK application provides access to the Terrain Integrated Rough Earth Model (TIREM) version 3.31. The plan for STK application version 13.1 is to remove TIREM 3.31, retain version 5.5, and add version 6.3. Once this occurs, running version 5.5 scenarios in the new STK application version will have no effect, but running version 3.31 scenarios will invoke TIREM 6.3 rather than TIREM 3.31, which would likely cause changes in your scenario results.
  • The Jupyter Notebooks UI plugin has been removed from the STK application, so you can no longer access Jupyter Notebooks from inside the application. You can still use Jupyter Notebooks outside of the STK application in the web browser.
  • The Java minimum version has been updated to Java 11 for the Parallel Computing Server Java API.

  • Support for the MrSID (*.sid) image format is deprecated and will be removed in a future release. If you are using MrSID images, you should convert them to JPEG 2000.