The MSS Specialty Group on Passive Sensors provides a forum for CLASSIFIED and controlled presentations, discussions, and dissemination of information regarding developments in passive sensor systems operating in the optical (ultraviolet through millimeter wave) spectrum. The group focuses on systems that exploit natural or man made emanations from the target and scene. The group addresses both tactical and strategic systems and considers all elements that make up a system from the entrance aperture through to the decision process, including any image processing that may be applied. The interest of Passive Sensors covers ground-, vehicle-, air-, ship-, and space-based sensors. Sensor functions include ISR, precision guidance, remote sensing, including seekers for surface-2-surface, surface-2-air, air-2-surface, air-2-air application; sensors that support target detection, recognition, and identification; sensors for situational awareness; sensors that sense the environment to improve understanding of the phenomenology and radiative transfer; sensors for foliage penetration and for terrain analysis; sensors for A2/AD environment; single-mode, multi-mode, multi-, and hyper-spectral; human-system interaction; sensors for remote and for autonomous operations; algorithms for meeting mission objectives, background clutter mitigation, including AI/ML/DL; algorithms and hardware based techniques to improve image quality such as super resolution, atmospheric compensation, turbulence mitigation; day/night operations. Technology can be at developmental, experimental, or operational stage.