Mechanical Engineering Design Intern - Summer

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.

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.

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.

• 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…