For those who prefer to get their hands dirty with code, the open-source ecosystem is thriving:

If you’re affiliated with a university, you can get (renewable). Ansys has a generous academic program that includes STK, MATLAB integrations, and more.

Check the official SpaceEngine website for free versions. 5. OpenOrbiter

First, a word of caution. Searching for cracked or “hot” unauthorized versions of STK or similar tools is risky. These downloads often contain: