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Salary: USD 145,000 - 185,000 / annual
Antares is building mass-producible, inherently safe, deployable microreactors for terrestrial, underwater, and space applications, with a mission to make clean energy abundant from Earth to the Asteroid Belt. The company has raised over $600M in venture capital and holds hundreds of millions in contracts with military services, NASA, and the Department of Energy.
As a Senior Thermal Analyst, you will own and drive the thermal design and analysis of a space nuclear vehicle, including the reactor, spacecraft, and heat rejection systems. You will develop, validate, and anchor thermal models to experimental and test data, using those models to guide early architecture decisions, system-level integration, and hardware design trades.
Key responsibilities include:
- Construct, own, and validate thermal models for the reactor core, spacecraft, radiator systems, and integrated vehicle thermal response
- Anchor thermal models to experimental, analytical, and test data; quantify uncertainty and improve model fidelity over time
- Identify gaps in thermal, materials, coolant-loop, radiator, and reactor heat-transfer data, and work with test engineers to define and interpret required tests
- Develop and analyze space nuclear thermal management architectures, including reactor heat transport, coolant loops, radiator systems, and integrated heat rejection systems
- Generate, compare, and downselect heat rejection system configurations across performance, mass, temperature, integration, reliability, manufacturability, and operational constraints
- Build system-level thermal models to assess vehicle-level performance, transient response, operating limits, and subsystem integration impacts
- Create tools, methods, and analysis processes for predicting radiator thermalization behavior and integrated thermal response
- Investigate and develop thermal hardware integration approaches, including coolant loop architectures, radiator panel integration, heat pipe coupling, and heat-transfer paths
- Support early-stage concept development through modeling-driven design trades and rapid evaluation of thermal system options
- Partner with reactor, mechanical, fluids, materials, test, and systems teams to ensure thermal design assumptions are reflected in hardware requirements and test plans
- Produce and review technical documentation, including thermal analyses, model validation reports, test plans, design trade studies, and design review materials
- Participate in formal and informal design reviews, ensuring thermal architecture, model assumptions, margins, and risks are clearly documented
The role focuses primarily on high-temperature thermal management for space nuclear systems, including reactor heat transport and radiator architectures, while also supporting traditional low-temperature spacecraft radiator design where required. You will work closely with cross-functional engineering teams in Antares' new 322,000 square-foot facility in Torrance, CA.
REQUIREMENTS:
Basic Qualifications:
- Bachelor's degree in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, Thermal Sciences, or related technical discipline
- 5+ years of experience in thermal engineering, thermal analysis, heat transfer, spacecraft thermal systems, nuclear systems, high-temperature systems, or closely related hardware development
- Strong fundamentals in conduction, convection, radiation, transient heat transfer, thermal-fluid systems, and system-level thermal modeling
- Experience building and validating thermal models using test data, experimental data, or flight/hardware data
- Experience performing thermal design trades and communicating model assumptions, uncertainty, margins, and design implications to cross-functional engineering teams
Preferred Skills & Experience:
- Master's degree or higher in Mechanical Engineering, Aerospace Engineering, Nuclear Engineering, Thermal Sciences, or related field
- Experience with spacecraft thermal control systems, radiators, heat pipes, thermal straps, louvers, MLI, coatings, spacecraft environmental interfaces, or orbital thermal analysis
- Experience with high-temperature thermal systems, nuclear thermal systems, reactor heat transport, Brayton/Rankine/Stirling-adjacent thermal architectures, pumped loops, liquid metal coolants, gas coolants, or refractory materials
- Experience developing or analyzing heat rejection systems for space, nuclear, defense, aerospace, or high-reliability energy systems
- Strong familiarity with Python and Git-controlled code repositories
- Familiarity with thermal modeling and simulation tools such as Thermal Desktop, SINDA/FLUINT, OpenTD, ANSYS, COMSOL, STAR-CCM+, or Fluent
- Experience developing reduced-order models, sizing tools, parametric trade tools, or integrated system models for thermal architecture studies
- Experience designing, executing, or interpreting thermal vacuum, component-level, coolant-loop, heat pipe, radiator, or high-temperature heat-transfer tests
- Understanding of radiator performance drivers, including view factors, emissivity, absorptivity, fin efficiency, thermal spreading, panel thermalization, degradation, and environmental effects
- Experience with coolant loop architecture, pump/valve/heat exchanger integration, pressure drop, flow stability, startup/shutdown transients, or two-phase/single-phase thermal-fluid systems
- Experience integrating thermal hardware into aerospace or nuclear systems, including structural interfaces, thermal expansion, manufacturability, inspection, reliability, and operations constraints
- Strong technical judgment in ambiguous design spaces, with the ability to make progress using incomplete data while clearly identifying risks and validation needs
- Strong communication skills, including the ability to explain complex thermal architectures, model assumptions, trade results, and test implications to engineers, program stakeholders, and leadership
Note: ITAR compliance required—applicant must be a U.S. citizen, national, lawful permanent resident, Refugee, or Asylee, or be eligible to obtain required authorizations from the U.S. Department of State.
