Senior GNC Engineer Long , California,

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.

The senior GNC Engineer will own guidance, navigation, and control for a new constellation‑ready spacecraft bus. The satellite bus uses a CMG‑based attitude control system with four Vast Mini CMGs in a pyramid configuration. You will 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 6

DOF simulation, hardware‑in‑the‑loop testing, and on‑orbit commissioning. You will engage directly with payload customers on pointing and stability requirements and define the CMG and sensor performance specs that drive hardware development and procurement across the program.

This is a full‑time, exempt position located in Long Beach.

• Define the ADCS architecture—including CMG pyramid configuration, sensor suite selection, and pointing modes.
• Develop GNC algorithms—attitude determination, CMG steering law, momentum management, and desaturation strategy.
• Own the pointing budget—accuracy, stability, jitter, and smear allocation across the sensor and actuator chain.
• Define the simulation strategy and build and validate the 6
  
  DOF simulation environment.
• Define CMG performance requirements—momentum capacity, gimbal rate, limits, and pyramid angle.
• Define sensor performance requirements—star tracker, IMU, sun sensor, magnetometer, GNSS receiver.
• Support CMG Rev 1 bring‑up with closed‑loop testing.
• Define and commission the HITL lab—flight processor, spoofed I/O, real‑time simulation.
• Model magnetic field for torque rod sizing.
• Run Monte Carlo analysis campaigns to demonstrate pointing performance.
• Assess flexible body dynamics and define appendage first‑mode frequency requirements.
• Engage directly with payload customers on feasibility, GNC data interfaces, and negotiation.
• Ensure cont rollability during electric propulsion maneuvers.
• Build a GNC team as the program scales—define roles and grow the team.
• Support on‑orbit commissioning planning for ADCS.

• Bachelor's degree in Aerospace, Mechanical, Physics, Mathematics, or a related discipline.
• At least 6 years of spacecraft GNC or ADCS development experience.
• Experience developing GNC algorithms—attitude determination, control law design, actuator management.
• Experience with reaction wheels or CMGs—actuator sizing, control allocation, momentum management.
• Built and validated 6
  
  DOF spacecraft simulations.
• Pointing budget development and allocation across sensor/actuator chains.
• HITL test environment design and execution.
• Comfortable working from architecture trades through flight software implementation.
• Strong dynamics and controls fundamentals.

• Ability to obtain a security clearance.
• CMG experience—steering laws, singularity avoidance, pyramid optimization.
• Momentum management for LEO spacecraft (magnetic desaturation, gravity gradient).
• Star tracker and IMU selection/characterization experience.
• Agile/small‑sat GNC development with small teams on fast timelines.
• GNC flight software implementation experience.

Pay Range:
California

$159,900 – $226,980 USD

Base salary, company equity, 100% medical, dental, and vision coverage for employees and dependents, generous paid time off, up to 20+ days of vacation for exempt staff and up to 10+ days for non‑exempt staff, paid parental leave, short‑ and long‑term disability insurance, life insurance, access to a 401(k) retirement plan, Class Pass credits, personalized mental healthcare, and other perks.

The person hired will have access to information and items subject to U.S. export controls and must be a “U.S. person” as defined by 22 C.F.R. § 120.62, or otherwise eligible for deemed export licensing.

Vast is an Equal Opportunity Employer; employment is governed on the basis of merit, competence, and qualifications and will not be influenced in any manner by race, color, religion, gender, national origin/ethnicity, veteran status, disability status, age, sexual orientation, gender identity, marital status, mental or physical disability or any other legally protected status.