Spectral Sciences' work in modeling rocket plumes and the atmospheric environment around spacecraft includes calculations of molecular flow and radiation fields using first-principles Monte Carlo simulation techniques. In collaboration with AFRL and other DoD agencies, SSI developed the SOCRATES (Spacecraft/Orbiter Contamination Representation Accounting for Transiently Emitted Species) software to predict the contamination and radiation environment around spacecraft. SOCRATES accurately models the interaction of a spacecraft's thruster exhaust with the atmosphere; calculating densities, reaction rates, and radiative emission rates for both steady-state and unsteady flows.
The SOCRATES software leverages the direct simulation Monte Carlo (DSMC) method with a primary focus for high altitude plume flow field and radiation calculations. It is designed for use as a research tool for specialists (it can simulate arbitrary species, arbitrary chemical reactions, trace species, etc.) and as a user-friendly tool for the non-specialist (it can run and produce useful results with very minimal input). Distribution of the software is restricted by U.S. export control regulations.