Senior Thermal 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 Thermal Engineer to define the thermal architecture and own thermal analysis for a new constellation-ready 15kW spacecraft bus — a product line designed to scale to hundreds of spacecraft per year. This will be a full-time, exempt position located in our Long Beach location. About this role:We're designing a high-power satellite bus that accommodates multiple payload types — including a compute-intensive Nvidia payload with significant thermal dissipation. The thermal architecture is a first-order design decision for this bus, not an afterthought. You'll own thermal analysis and design from system architecture through flight delivery, starting during the architecture trade studies.The thermal challenges span the full range: multiple payload configurations with different thermal profiles, high-power-density electronics with demanding heat rejection requirements, and a production-rate design that must be repeatable across hundreds of spacecraft. You'll start as the sole thermal engineer and build a team as the program scales.Responsibilities: Define the thermal control architecture — trade passive, heat pipe, and pumped fluid loop approaches, radiator sizing and placementPerform system-level and component-level thermal analysis for the satellite bus across all payload configurationsAddress the high-power thermal challenge — Nvidia compute module drives heat rejection requirements that may force the architectureContribute first-order thermal models to the spacecraft design, simulation, and digital twin tool for fast design iteration, then validate using traditional analysis tools (e.g., Thermal Desktop)Develop and maintain the detailed system thermal modelOwn the thermal budget — min/max temperatures per component vs qualification limits, across all orbital conditionsSelect thermal coatings and materials (AZ-93, S13G, Kapton, Aeroglaze, etc.)Specify and procure emissivity control materials and RTDs (temperature sensors)Plan TVAC test campaigns — define chamber requirements, test profiles, success criteria (feeds facility planning)Correlate thermal models to test data after environmental testingSupport solar array thermal analysis (coordinate with solar array team lead)Support box-level thermal design for new clean-sheet avionics designs — power dissipation, interface temperatures, mounting thermal resistanceMinimum Qualifications:Bachelor's degree in Mechanical Engineering, Aerospace Engineering, or a related technical discipline6+ years of spacecraft or aerospace thermal engineering experienceSpacecraft thermal control design and analysis experience — passive and active systemsBuilt and correlated thermal models for flight hardwareExperience with high-power / high-dissipation thermal challengesFamiliar with thermal coatings, MLI, radiators, heat pipes, thermal strapsTVAC test planning and execution experienceComfortable working during early architecture phases — you can make thermal architecture recommendations with incomplete data and refine as the design maturesExperience across multiple thermal analysis tools (Thermal Desktop, SINDA, ESATAN, or equivalent)Preferred Skills & Experience:Able to obtain a security clearanceExperience with multi-satellite builds where thermal design must be consistent across unitsHigh-power-density thermal design experienceThermal design for payloads with variable duty cyclesCryogenic or specialized thermal control experiencePay Range: California$147,600—$209,520 USDCOMPENSATION AND BENEFITSBase salary will vary depending on job-related knowledge, education, skills, experience, business needs, and market demand. Salary is just one component of our comprehensive compensation package. Full-time employees also receive company equity, as well as access to a full suite of compelling benefits and perks, including: 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 of vacation for non-exempt staff with the ability to cash-out unused vacation annually, paid parental leave, short and long-term disability insurance, life insurance, access to a 401(k) retirement plan, ClassPass credits, personalized mental healthcare through Spring Health, and other discounts and perks. We also take pride in offering exceptional food perks, with snacks, drip coffee & onsite barista, cold drinks, and dinner meals remaining free of charge, and lunch subsidized as part of Vast’s ongoing commitment to providing high-quality meals for employees.U.S. EXPORT CONTROL COMPLIANCE STATUSThe person hired will have access to information and items subject to U.S. export controls, and therefore, must either be a “U.S. person” as defined by 22 C.F.R. § 120.62 or otherwise eligible for deemed export licensing. This status includes U.S. citizens, U.S. nationals, lawful permanent residents (green card holders), and asylees and refugees with such status granted, not pending.EQUAL OPPORTUNITYVast is an Equal Opportunity Employer; employment with Vast 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.