<p>Quantum devices flown in Low Earth Orbit (LEO) are exposed to hostile environments where cosmic rays, solar radiation, and long-lived material defects induce temporally correlated noise. In such scenarios, the well-known Markovian Lindblad formalism may be insufficient for correlated noise scenarios, as the memory less bath assumption is broken. In this work, we bridge formal non-Markovian frameworks (Nakajima–Zwanzig and Time-Convolutionless master equations) with an accessible stochastic method based on the Ornstein–Uhlenbeck (OU) process, resulting in a tractable surrogate model of colored noise with finite correlation time. We solve the corresponding stochastic Schrödinger equation and recover reduced dynamics through ensemble averaging. Numerical simulations reveal three characteristic signatures of non-Markovian dynamics: (i) partial protection and revivals of coherence, (ii) trajectory-dependent fluctuations in fidelity, and (iii) information backflow as quantified by the Breuer–Laine–Piilo measure. For the simulated parameters, the OU model extends the effective coherence time by a factor of approximately 1.5 compared to the Markovian case, while maintaining higher fidelity for longer times. These findings indicate both the benefits and challenges of non-Markovian effects for space-based quantum systems. They provide practical insight for quantum communication (e.g. satellite QKD), sensing, and computation in orbit, and suggests non-Markovian noise modeling as a promising approach for designing robust and radiation-hardened quantum technologies in space.</p>