Spacecraft Design Engineer - Space Nuclear

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.

Formed in 2023, the Antares team hails from SpaceX, The White House, MIT, Rigetti Computing, The Air Force, General Atomics, Relativity Space, Ursa Major, and National Laboratories like Los Alamos, Idaho, and Oak Ridge. Antares has raised over $130M in venture capital from top-tier investors and has over $13M in government funding.

About the Team

As a Spacecraft Mechanical & Mechanisms Design and Integration Engineer in Antares’ Mission Engineering team, you will own the design and integration of cutting-edge nuclear terrestrial and space systems. From concept through fabrication and deployment, you’ll develop spacecraft, testbed, and vehicle layouts that unify reactor, power conversion, heat rejection, and payload systems into a cohesive architecture. You’ll drive trades on system layout, interfaces, packaging, working closely with cross-disciplinary teams to refine configurations and close design loops. Your responsibilities will span CAD integration, mass properties management, and precise definition of thermal and mechanical interfaces to ensure the system satisfies requirements and is manufacturable.

Roles and Responsibilities:

• Lead the configuration and integration of terrestrial and space nuclear systems and testbeds including reactor, power conversion, thermal rejection, shielding, and structural elements.

• Drive system-level layout, mass properties, and integration decisions across all phases of design, from concept through CDR.

• Own CAD integration models and configuration baselines

• Drive cross-discipline alignment and trade studies.

• Coordinate closely with subsystem leads (nuclear, thermal, structures) to ensure a system architecture that satisfies requirements.

• Support design reviews and integration/test planning for hardware.

Basic Qualifications:

• Bachelor’s degree in mechanical or aerospace Engineering, or a related physics-based field.

• Minimum of 5+ years of experience in vehicle configuration.

• Expertise with CAD (e.g., NX, CATIA) and past experience with PLM and other manufacturing planning and management systems.

Preferred Skills & Experience:

• Master’s or PhD in mechanical or aerospace Engineering, or a related physics-based field.

• Expertise in the design, analysis, and integration of space and/or nuclear systems.

• Experience in nuclear or other high temperature systems.

• Leadership experience on a project or research team.

• Strong project management skills, cross discipline communication, and interpersonal and collaborative skills.

• Exceptional communication skills to work effectively across teams and convey technical information to non-specialists.

• Understanding of fundamental principles in fluid systems and solid mechanics.

• Demonstrated track record of initiative and high impact / ROI contributions.

• Broad knowledge of materials science and material selections, especially for nuclear applications.

Additional Requirements:

• Ability to work nights and weekends as needed to meet business milestones

Location

• We are located in Torrance, CA in a 145,000 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”

• Craftsmen - We also focus on the inputs. We aspire to high-quality engineering for its own sake. As such, we invest in personal growth, learning, and developing a long-term career path for exceptional individual contributors. We embrace a beginner’s mindset, share knowledge, and never condescend the curious

• Seriously Optimistic - We’re ambitious and we believe we’re capable of achieving things others believe are impossible. We reward audacity and don’t let cynicism, sarcasm, snark, or belittlement influence us to lower the bar

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.