Senior GNC Engineer

At Vast, our mission is to contribute to a future where billions of people are living and thriving in space. Vast is developing next-generation space stations to ensure a continuous human presence in space for America and its allies, enabling advanced microgravity research and manufacturing, and unlocking a new space economy for government, corporate, and private customers. Using an incremental, hardware-rich and low-cost approach, Vast is rapidly developing its multi-module Haven Station. Haven Demo’s 2025 success made Vast the only operational commercial space station company to fly and operate its own spacecraft. Next, Haven-1 is expected to become the world’s first commercial space station when it launches, followed by additional Haven modules to enable permanent human presence by 2030. Our team is all-in, committed to executing our mission safely and on time. If you want to work with the most talented people on Earth furthering space exploration for humanity, come join us. Vast is seeking a Senior GNC Engineer to own guidance, navigation, and control for a new constellation-ready spacecraft bus — a product line designed to scale to hundreds of spacecraft per year. The satellite bus uses a CMG-based attitude control system — four Vast Mini CMGs in a pyramid configuration. ADCS performance is a defining capability of the bus — it's what enables high-power payloads that demand precise pointing and rapid slew. You'll own the GNC algorithms, simulation environment, sensor suite definition, and pointing performance for the satellite. This is end-to-end ADCS ownership: from architecture trades and algorithm development through 6DOF simulation, hardware-in-the-loop testing, and on-orbit commissioning. You'll engage directly with payload customers on pointing and stability requirements, and you'll define the CMG and sensor performance specs that drive hardware development and procurement across the program. This will be a full-time , exempt position located in our Long Beach location. Responsibilities: Define the ADCS architecture — CMG pyramid configuration, sensor suite selection, pointing modes (nadir+yaw steer, LVLH fixed, 3-axis sun tracking) Develop GNC algorithms — attitude determination, CMG steering law (including singularity avoidance), momentum management, desaturation strategy Own the pointing budget — pointing accuracy, stability, jitter, and smear allocation across the sensor and actuator chain Define the simulation strategy — determine how the spacecraft design, simulation, and digital twin tool and Vast’s flight-validated 6DOF physics sim (GTsim) work together, what fidelity is needed for upfront system design vs flight readiness Build and validate the 6DOF simulation environment Define CMG performance requirements — momentum capacity, gimbal rate, gimbal limits, pyramid angle — feeding the electronics lead for box design Define sensor performance requirements — star tracker, IMU, sun sensor, magnetometer, GNSS receiver accuracy and noise specs (feeding the procurement lead for vendor selection) Support CMG Rev 1 bring-up with closed-loop testing Define and commission the HITL (hardware-in-the-loop) lab — flight processor, spoofed I/O, real-time simulation Magnetic field modeling for torque rod sizing Run Monte Carlo analysis campaigns to demonstrate pointing performance and flight readiness Assess flexible body dynamics — structural mode coupling with large solar arrays and cantilevered payloads, define appendage first-mode frequency requirements for structures Engage directly with payload customers on pointing and stability requirements — assess feasibility on the bus, define GNC data interfaces, and negotiate what we can support Ensure controllability during electric propulsion maneuvers — coordinate with the EP team on thrust vector, disturbance torques, and momentum impact Build a GNC team as the program scales — define roles and hire as complexity demands Support on-orbit commissioning planning for ADCS Mini…