Senior Thermal Engineer, Lunar

Vast is developing next-generation space stations and space infrastructure using an incremental, hardware-rich, and low-cost approach. Vast is rapidly developing its multi-module Haven Station 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. 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 in 2027, followed by additional Haven modules. Additionally, the company recently announced Vast Satellite, a high-power satellite product line leveraging its space station components and the heritage of Haven Demo.

Headquartered in Long Beach, California, and with more than 1,000 employees and over a billion dollars in private capital, Vast has built the facilities required to manufacture and operate America’s next space station. The company plans to develop future habitats and systems for the Moon and Mars, dedicated space stations for government partners, and other crewed systems that will unlock the expanding long-term space economy.

Vast is seeking a Senior Thermal Engineer, Lunar, reporting to the SVP, Lunar Programs, to own thermal architecture and analysis for Vast's lunar surface elements — a surface power station and a crewed habitat, airlock, and node designed to survive and operate through the full lunar diurnal cycle.

As one of the founding engineers on the Lunar team, you'll play an essential role in developing Vast's lunar ecosystem. In this role you will serve as the lead for thermal control of hardware destined for the lunar surface - defining, analyzing, and qualifying the radiators, fluid loops, heat pipes, MLI, coatings, and survival heating architecture that will keep crewed and non-crewed lunar systems alive. You will own the thermal architecture end-to-end, from first-order trades through model correlation and flight, and help establish the thermal design standards, margin policy, and environment definitions that Vast's lunar hardware will be built on.

This will be a full-time, exempt position located in our Long Beach location.

Responsibilities:

Define the thermal control architecture for Vast's lunar surface elements - trading passive, heat pipe, pumped fluid loop, and thermal storage approaches against mass, power, complexity, and dust exposure

Size and place radiators for the lunar surface environment, accounting for diurnal sink temperature swings, albedo and lunar IR loading, terrain and self-view blockage, and latitude-driven constraints

Own the survival thermal case through lunar night - heater power budget, thermal mass and phase-change storage strategy, and dormancy and wake-up thermal states

Own the habitat, airlock, and node thermal control - cabin temperature and humidity control, condensing heat exchanger, coolant loop architecture, and depress/repress thermal transients

Build and maintain the detailed system thermal models, contribute reduced-order models to Vast's design, simulation, and validate against Thermal Desktop, SINDA/FLUINT, or equivalent

Own the thermal budget: min/max predicted temperatures per component against qualification limits across launch, cruise, descent, landed day, landed night, and off-nominal conditions

Select thermal coatings, MLI, heat pipes, thermal straps, isolators, heaters, and RTDs for the lunar environment, with explicit accounting for regolith dust deposition, abrasion, and UV degradation of end-of-life optical properties

Plan and execute TVAC and thermal balance test campaigns (chamber and shroud requirements, solar and IR simulation, cold-case survival demonstration, test profiles and success criteria), then correlate models to test data

Establish the thermal design standards, margin policy, and lunar environment definitions Vast's lunar hardware will be built on, and support design reviews, drawing checks, and NASA technical deliverables

Minimum Qualifications:

Bachelor's degree in Mechanical Engineering, Aerospace Engineering, Physics or a related technical discipline

6+ years of spacecraft or aerospace thermal engineering experience

Spacecraft thermal control design and analysis experience

Built and correlated thermal models for flight hardware

Experience with extreme-environment or wide-swing thermal design where both hot and cold cases were design-driving

Familiar with thermal coatings, MLI, radiators, heat pipes, thermal straps, and heater/thermostat design

Comfortable working during early architecture phases

Experience across multiple thermal analysis tools (Thermal Desktop, SINDA/FLUINT, ESATAN, or equivalent)

Preferred Skills & Experience:

TVAC and thermal balance test planning and execution experience, preferred

Lunar or planetary surface thermal experience, including diurnal survival design (thermal switches) and regolith conduction modeling

Crewed vehicle thermal experience: cabin ATCS, condensing heat exchangers, humidity control, ECLSS thermal interfaces, or touch temperature compliance for human-rated hardware

Airlock, EVA systems, or suit thermal experience, including depress/repress thermal transients

Pumped fluid loop design - working fluid selection, pump and accumulator sizing, freeze protection, and loop control

Familiarity with lunar dust effects on thermo-optical properties and dust mitigation strategies

Additional Requirements:

Willingness to work evenings and/or weekends to support critical mission milestones

Ability to travel up to 5% of the time to support customer meetings

Pay Range: California$147,000—$249,000 USD

We calibrate level and compensation to the selected candidate's experience and demonstrated capability. We welcome applicants across a range of experience levels to apply.

COMPENSATION 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.

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.