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Apex manufactures satellite buses at scale for the commercial space industry. The company combines software, vertical integration, and hardware designed for manufacturing to enable spacecraft platforms that support earth observation, communications, and other critical missions.
You will own the end-to-end design, development, qualification, and production of cathode technology for Apex's electric propulsion systems. This is a senior individual-contributor role with technical leadership scope across the cathode program.
Key responsibilities include:
- Own hollow and heaterless cathode design from emitter physics through thermal-mechanical design, cathode-thruster coupling, life characterization, and design-for-manufacturing at production rate.
- Develop physics-based and empirical models to predict cathode performance, discharge behavior, thermal margins, and life; validate against test data.
- Define and execute cathode test and life-qualification campaigns in vacuum facilities, including ignition, conditioning, voltage characterization, thermal cycling, plume diagnostics, wear testing, and long-duration life tests.
- Drive cathode-thruster integration, optimizing coupling, mass flow split, and placement for overall system performance and stability.
- Establish erosion, poisoning, and degradation models; perform filtration and contamination-control analysis; demonstrate compliance with propulsion budgets.
- Select and qualify emitter and structural materials (LaB6, BaO-impregnated tungsten, refractory metals) for spaceflight and high-rate production.
- Optimize designs for weight, cost, manufacturability, and repeatability; develop work instructions, process flows, and AI&T procedures for production.
- Partner with systems, power electronics, thermal, structures, and avionics teams to define interfaces and verify requirements.
- Support flight hardware build, integration, test, and launch campaigns; evaluate on-orbit performance and resolve anomalies.
- Lead failure analysis, root-cause investigations, and continuous improvements.
- Mentor propulsion engineers and build Apex's cathode and electric propulsion capability.
You will set the cathode technical roadmap, drive key design decisions, run qualification campaigns, and mentor the team as EP production scales. This role offers the opportunity to approach cathode development with a production-first mindset and build the capability and infrastructure around it.
Requirements:
- Bachelor's degree in aerospace, mechanical, electrical, plasma/propulsion engineering, applied physics, or related field.
- 10+ years of relevant electric propulsion experience with Bachelor's or Master's degree, OR Ph.D. in electric propulsion, plasma physics, applied physics, or closely related field with 5+ years of relevant industry experience. Substantial, demonstrable focus on cathode design, development, and testing required.
- Deep, hands-on knowledge of hollow and/or heaterless cathode physics: thermionic emission, emitter materials, plasma discharge behavior, keeper/orifice design, cathode coupling to Hall or ion thrusters.
- Experience planning and executing cathode or EP test campaigns in vacuum facilities, including plasma diagnostics, performance measurement, and long-duration life/wear testing.
- Strong understanding of cathode failure and degradation mechanisms: emitter depletion, erosion, poisoning, contamination; ability to design and test against them.
- Working knowledge of spacecraft propulsion system architecture, propellant feed systems, and range safety requirements (e.g., SSCMAN 91-710).
- Ability to decompose requirements and ICDs; clear communication across engineering disciplines.
- Must be a U.S. Person (U.S. citizen, lawful permanent resident, or protected individual) as defined by ITAR (22 CFR §120.15).
Nice to have:
- Direct experience taking a cathode or EP thruster from development through flight qualification and on-orbit operation.
- Experience with heaterless cathode ignition and conditioning schemes.
- Experience with alternative propellants (krypton, non-xenon) and their effects on cathode life and operation.
- Familiarity with PPU/cathode drive electronics and power interface definition.
- Design-for-manufacturing experience bringing propulsion hardware into serial or high-rate production.
- Experience with EP environmental qualification (vibration, TVAC, EMI testing of flight propulsion hardware).
