How do I perform conjunction assessment analysis in STK?

Great question! Performing collision avoidance analysis in STK can be quite detailed, but I'll walk you through the basic steps. Here's how you can do it:

1. Create a New Scenario:
   • Open STK and create a new scenario. Set the start and stop times for your analysis period.
2. Update TLE Databases:
   • Ensure you have an internet connection and update your satellite database to get the most accurate positional data.
   • Go to [Update Database] in the STK menu. 
   • Select the [Update Now] to update the Satellite database.
3. Load Satellite Data (Ephemeris):
   • Load the ephemeris file for your primary satellite and secondary satellites (if you have ephemeris for the secondary satellites). It is recommended to use ephemeris for at least the primary satellite. Using TLE vs TLE provides medium accuracy results where Ephemeris vs. TLE is higher accuracy depending on the accuracy of the ephemeris. Ephemeris vs Ephemeris is most ideal because Ephemeris usually comes with Covariance. 
4. Set Up Conjunction Analysis:
   • Create a new AdvCAT object to set up your analysis.
   • Define the primary and secondary objects and set the threat volume parameters.
   • Define the Time, usually I use the ephemeris time of the primary satellite as long as there is ephemeris for the secondary object. 
5. Compute Conjunction Analysis 
   • Press the Compute Button 
   • Check the Message Viewer to see if there are any errors. 
6. Analyze Results:
   • Open the Report and Graph Manager, and run the Close Approach by Min Range or by SSC. 
   • This will tell if you have any conjunctions. No results could mean safely or you did not calculate correctly. Please verify your inputs before assuming the primary satellite is risk free. 

Hope this helps!