Spacecraft operators are increasingly exploring distributed mission concepts and moving to more remote regimes, presenting new technical challenges that can be addressed by onboard autonomy capabilities. Onboard planning enables new tasks to be assimilated independently of ground commands, enhancing near-Earth operations and enabling remote operations. Modern sensor algorithms can run locally on spacecraft to detect potential tasks, such as data collection opportunities for civil science missions, or launch events for defense missions. Planning capabilities are needed to prioritize and schedule tasks with overlapping windows of opportunity without the need for human intervention. Our proposed innovation, which we call Adjutant, is flight software (FSW) for planning that leverages state of the art optimization methods for scalability and relevance to current operations, an open systems approach to plan management from multiple sources, and code generation to simplify mission integration and reduce development time for operators. Adjutant is directly relevant to applications identified in our subtopic, such as missions operating autonomously and cooperatively at cislunar or more remote destinations by reducing and eventually eliminating the need for ground-based semiautonomous scheduling. Reducing the need for ground-based operations enables more efficient operation of near-Earth constellations, and can be extended to enable persistent remote operations in Cislunar or more remote environments. Our proposed Phase II extension will develop FSW prototypes of planning, goal monitoring, and plan management applications. In conjunction with our existing FSW applications, Adjutant will enable onboard planning and execution of complex missions, including activities such as station keeping, navigation, and fault recovery. Onboard planning will support missions including Earth science such as Landsat Next, heliophysics such as GDC, and exploration such as LunaNet. Potential NASA Applications (Limit 1500 characters, approximately 150 words): Exploration Missions? LunaNet? Venus Flagship Mission? Lunar Gateway? Heliophysics? Geospace Dynamics Constellation? HelioSwarm? Solar-Terrestrial Observer for the Response of the Magnetosphere? Earth Observation Missions? Landsat Next? FireSat Potential Non-NASA Applications (Limit 1500 characters, approximately 150 words): Space Development Agency (SDA) National Defense Space Architecture Tracking Layer & Transport Layer? Air Force Research Laboratory (AFRL)? Cislunar Highway Patrol System (CHPS): remote operations in Cislunar space? Commercial: Enable dynamic replanning in between contact with ground stations? Earth-observing constellation operators, e.g.:? Planet, Capella?, Hawkeye 360 Duration: 24