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Mechanical Engineering Design Intern - Summer 2027

Antares· Los Angeles, CA· Reactor Hardware Engineering

Factory-built fission microreactors for power on Earth, in space, undersea · Posted today

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 Summer Internship Program

Internships at Antares are anything but ordinary. You'll work alongside our team as we design, build, and test fission microreactors built to deliver reliable energy for critical missions on Earth, in space, and underwater.

Our interns contribute to real work from day one. Depending on your role, you may touch hardware, write and test software, support manufacturing and operations, or help build the systems that allow Antares to move quickly as we scale. You'll work alongside engineers, operators, and other experts solving challenging problems—and you'll leave your internship with hands-on experience that's difficult to find anywhere else.

We work hard, move quickly, and take pride in what we're building. If you're excited to learn by doing and want to contribute to the next generation of nuclear energy, we'd love to have you join us next summer.

We will be running two separate cohorts to accommodate students on both semester and quarter schedules:

Cohort #1

Monday, May 17 – Friday, August 13

Cohort #2

Monday, June 14 – Friday, September 10

All internship roles are based at our Torrance headquarters and require interns to work onsite five days per week. We will not be considering candidates for remote or hybrid arrangements. Interns will receive a relocation and housing stipend as part of their offer package.

About the Team

Antares is seeking a Mechanical Design Intern to support the design, analysis, and testing of Mark-1 and JANUS-1 components. You will be paired with a Responsible Engineer and take meaningful ownership of a defined set of components within one of our engineering systems.

You will begin with focused starter assignments before transitioning to a longer-duration project that culminates in a technical deliverable and presentation. Interns are integrated into the engineering organization and evaluated with expectations comparable to those of a first-year engineer. Success requires technical curiosity, initiative, sound judgment, and the ability to use mentorship and cross-functional resources effectively.

Roles and Responsibilities:

  • Support the design, analysis, development, and testing of mechanical components for Mark-1 and JANUS-1.

  • Own a defined component or project scope under the guidance of a Responsible Engineer.

  • Create and refine engineering designs, analyses, drawings, test plans, and technical documentation.

  • Participate in design reviews and clearly communicate technical decisions, assumptions, risks, and results.

  • Work with engineering, manufacturing, test, and other cross-functional teams to resolve technical challenges.

  • Identify design issues and opportunities to improve performance, reliability, manufacturability, and testability.

  • Execute a long-duration engineering project and present the final results and recommendations to the broader team.

  • Seek feedback, incorporate lessons learned, and demonstrate increasing independence throughout the internship.

Basic Qualifications:

  • Currently enrolled in a bachelor’s degree program in mechanical engineering, aerospace engineering, or a related discipline.

  • Entering the junior or senior year of study.

  • 6+ months experience of technical engineering skills outside of the university setting classroom (eg: laboratory, research, extracurricular project teams, volunteering, personal projects or prior internship/work experience)

Preferred Skills & Experience:

  • GPA of 3.5 or higher.

  • Experience with a university engineering club, competition team, research group, or technical organization; leadership experience is preferred.

  • Strong analytical and problem-solving skills with close attention to detail.

  • Strong interpersonal, written, and technical communication skills, such as leading a student project team or presenting research.

  • Ability to work effectively across departments and technical disciplines.

  • Comfort working in a dynamic environment with evolving needs and requirements.

  • Ability to work independently, take initiative, and contribute effectively within a team.

  • Experience with mechanical CAD, engineering drawings, analysis, prototyping, or hardware testing is a plus.

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 Is - 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.

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