Test Engineer II-Senior

About Us

At Antares, our long-term mission is to make clean energy abundant from Earth to the Asteroid Belt. We’re fueled by the belief that advanced nuclear energy can strengthen our military, solve the climate crisis, elevate global living standards, and expand humanity's presence in outer space. To achieve our mission, we’re building mass-producible, inherently safe, deployable microreactors that can be used terrestrially, underwater, and in space.

The Antares team hails from SpaceX, the White House, the Pentagon, the Department of Energy, MIT, Rigetti Computing, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Idaho, Oak Ridge, Los Alamos, and Savannah River. Antares has raised over $600M in venture capital from top-tier investors and has hundreds of million-dollars on contract with the military services, NASA, and the Department of Energy.

About the Team

As a Test Engineer in Antares’ Test Engineering team, you will design, build, and own test infrastructure for our R1 microreactor. You will develop end-to-end test plans - from concept to data analysis - for components and subsystems spanning heat rejection, power distribution, thermal management, and mechanical systems.

You will help develop and document our testing best practices, requirements, and workflows to enable rapid iteration and high-quality data.

You will collaborate with cross-functional teams to ensure that prototype, development, and qualification hardware is designed with respect to a test plan that validates critical features and performance parameters. You will design, validate, and maintain test setups to ensure the required precision and accuracy.

Roles and Responsibilities:

• Architect, build, and employ bespoke test stands and rigs for heat pipe components and assemblies

• Develop comprehensive test plans and protocols: instrumentation, execution steps, pass/fail criteria, and data analysis workflows

• Build test schedules and ensure alignment with development and business needs

• Lead test design and readiness reviews and communicate approach and results with stakeholders

• Validate measurement precision and accuracy; procure or design specialized fixtures and sensors as needed

• Create schematics and CAD models of test setups and facilities

• Define standard processes and workflows for prototype, qualification, and production-grade testing

• Provide subject matter expertise on test methods, including mentoring teammates

• Participate in root cause investigations and implement corrective actions to prevent repeat failure

Basic Qualifications:

• Bachelor’s degree in physics or an engineering discipline

• 2+ years of hands-on test engineering experience

• Experience designing assemblies and test fixtures using CAD

• Experience integrating and using test instrumentation (pressure transducers, thermocouples, strain gauges, relays, solenoid valves, etc.)

Preferred Skills & Experience:

• Master’s degree or higher in mechanical or aerospace engineering

• 5+ years of hands-on test engineering experience

• Experience designing and building test rigs and executing thermal and mechanical tests

• Experience with LabVIEW, Simulink, or similar test software

• Experience testing thermal management or heat-rejection systems, or vacuum-relevant components

• Experience in mechanical, durability, or materials testing

• Leadership experience on a project or research team

• Strong project management and cross-disciplinary communication skills

• Demonstrated track record of high-impact technical contributions

• Experience with part inspection technologies (micrometers, CMM, white light scanning, etc.)

• Knowledge of PLM, ERP, and related manufacturing systems

• Strong Python or general programming experience

Additional Requirements:

• Ability to work long hours and weekends as necessary to support critical milestones

• Ability to lift 25 lbs; role may require standing, climbing, bending, grasping, sitting, pulling, pushing, stooping, stretching, and carrying

Compensation:

• Test Engineer II: $112,000-$150,000

• Senior TestEngineer: $140,000-$185,000

Location

• We are located in Torrance, CA in a 322,000 square foot, brand new facility featuring large open spaces for team collaboration, R&D, and production, as well as easy access to the 405, 105, and 110 freeways. Our facility is in the heart of Los Angeles' vibrant emerging tech ecosystem alongside many other high growth startups and enterprises.

Culture

At Antares, we like to specifically tie each role to our founding document’s set of values–here are the top five cultural values we think you should believe at your core to be successful:

• Think in Systems - Energy and Defense are complex ecosystems with numerous stakeholders with competing priorities, conflicting policies, perverse incentives, and emergent and path-dependent properties. First principles thinking alone is insufficient. Think probabilistically and then take action. “If you want to be certain, then you are apt to be obsolete.” Over-optimizing the components often degrades the system

• Obsess over the End User - The customer and end user are often not the same. We will never build globally competitive commercial products if we lose sight of our end users and their entire interaction with the product life cycle

• Be Unconstrained by Convention - Our only limits are the laws of physics. Many, even experts, will say what we are working on is impossible. They said the same about SpaceX reusing rockets. Generationally impactful companies, by definition, must accomplish the seemingly impossible. If it were easy, it would have already been done. Never shy away from a solution because it has never been tried before, and never choose to do something because that's “how it's always been done”

• Go Where the Work I s - Never miss a chance to meet a customer, user, or stakeholder face to face, even if that means hopping on a plane. If you can’t make it, find a teammate who can channel your intentions and go in your place. Deep work can be done from anywhere, but we believe teams are built in person, and aim to maximize our time together

• Operate in the Grey - Embrace nuance in pursuit of truth. Question every fundamental assumption

Equal Opportunity

Antares is an Equal Opportunity Employer. Employment decisions are based solely on merit, competence, and qualifications, without regard to 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.

ITAR Requirements

To conform to U.S. Government export regulations, applicant must be a (i) U.S. citizen or national, (ii) U.S. lawful, permanent resident (aka green card holder), (iii) Refugee under 8 U.S.C. § 1157, or (iv) Asylee under 8 U.S.C. § 1158, or be eligible to obtain the required authorizations from the U.S. Department of State. Learn more about the ITAR here .