Senior Thermal Engineer

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 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 placement

• Perform system-level and component-level thermal analysis for the satellite bus across all payload configurations

• Address the high-power thermal challenge — Nvidia compute module drives heat rejection requirements that may force the architecture

• Contribute 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 model

• Own the thermal budget — min/max temperatures per component vs qualification limits, across all orbital conditions

• Select 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 testing

• Support 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 resistance

Minimum Qualifications:

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

• 6+ years of spacecraft or aerospace thermal engineering experience

• Spacecraft thermal control design and analysis experience — passive and active systems

• Built and correlated thermal models for flight hardware

• Experience with high-power / high-dissipation thermal challenges

• Familiar with thermal coatings, MLI, radiators, heat pipes, thermal straps

• TVAC test planning and execution experience

• Comfortable working during early architecture phases — you can make thermal architecture recommendations with incomplete data and refine as the design matures

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

Preferred Skills & Experience:

• Able to obtain a security clearance

• Experience with multi-satellite builds where thermal design must be consistent across units

• High-power-density thermal design experience

• Thermal design for payloads with variable duty cycles

• Cryogenic or specialized thermal control experience

Pay Range: California

$147,600—$209,520 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.