A

Antares Nuclear

Develops autonomous microreactors for remote power

Reliability Engineer 2-Senior

Full-TimeUpdated on 10/23/2026
$115k - $190k/yr
Mid, Senior
Bachelor's
Torrance, CA, USA
In PersonOn-site at the Torrance, California facility; the culture statement encourages occasional travel to meet customers, users, or stakeholders.
Mechanical EngineeringMechanical Maintenance and Reliability Engineering

About the job

Requirements
  • A bachelor's degree in engineering, applied mathematics, physics, statistics, or a related technical field.
  • Experience performing reliability, root cause analysis, failure analysis, statistical analysis, or similar quantitative engineering work on complex hardware systems.
  • Working knowledge of statistics, probability, failure modes, and reliability engineering fundamentals.
  • Ability to understand mechanical and electrical systems well enough to evaluate likely failure mechanisms and reliability risks.
  • Ability to analyze technical data, develop quantitative conclusions, and communicate recommendations to engineering teams.
Responsibilities
  • Own quantitative reliability analysis for the Antares R1 microreactor, including development and maintenance of reactor- and plant-level reliability, availability, and capacity factor models.
  • Establish reliability targets for reactor systems, subsystems, and critical components based on overall plant capacity factor, regulatory requirements, and mission requirements.
  • Translate top-level reactor availability and capacity factor goals into measurable reliability requirements for individual mechanical, electrical, controls, thermal, and balance-of-plant systems.
  • Develop and maintain reliability block diagrams, fault trees, failure mode analyses, and other quantitative models used to understand how component and subsystem failures affect overall reactor performance and availability.
  • Calculate and track key reliability metrics, including failure rates, mean time between failures, mean time to repair, availability, probability of mission success, component life, and expected contribution to reactor downtime.
  • Identify the components and failure modes that have the greatest impact on reactor capacity factor and lead focused improvement efforts to reduce those risks.
  • Work directly with mechanical, electrical, controls, manufacturing, test, and reactor systems engineers to develop reliability improvement plans for the lowest-performing or highest-risk portions of the design.
  • Evaluate design alternatives and architecture trades based on their impact on reliability, redundancy, maintainability, serviceability, and reactor capacity factor.
  • Perform sensitivity and uncertainty analyses to determine which assumptions, failure rates, repair times, and component behaviors most strongly influence predicted reactor availability.
  • Develop reliability predictions using component test data, supplier data, industry databases, accelerated life testing, engineering analysis, and field experience.
  • Establish statistically sound methods for converting development and qualification test results into reliability estimates and confidence bounds.
  • Define reliability demonstration and qualification test strategies, including sample sizes, test durations, failure criteria, confidence levels, and statistical acceptance methods.
  • Use operational, manufacturing, inspection, and test data to continuously update reliability models and improve predictions as the reactor design matures.
  • Lead or support design failure mode and effects analysis, failure mode and effects analysis, failure mode, effects, and criticality analysis, fault tree analysis, and related structured failure-mode investigations across reactor systems.
  • Partner with design teams early in the development process to identify single-point failures, wear-out mechanisms, common-cause vulnerabilities, inadequate redundancy, difficult-to-maintain components, and other reliability risks before designs are released.
  • Evaluate component degradation and life-limiting mechanisms, including fatigue, creep, wear, corrosion, thermal cycling, radiation exposure, electrical degradation, and environmental effects as applicable to the reactor design.
  • Develop reliability growth plans for systems that do not initially meet program targets and track progress toward demonstrated reliability objectives.
  • Support decisions regarding redundancy, sparing, preventative maintenance, inspection intervals, replacement intervals, and repair strategies based on quantitative reliability and availability analysis.
  • Work with operations and deployment teams to understand expected maintenance and repair activities and accurately incorporate those activities into reactor availability and capacity factor predictions.
  • Establish clear reliability dashboards, metrics, and technical reviews that allow engineering leadership to understand the major drivers of reactor downtime and where engineering effort should be focused.
  • Communicate reliability risks and recommendations clearly to engineers and program leadership, including the quantitative impact of proposed design or operational changes on overall reactor performance.
  • Serve as a technical authority for reliability engineering methods and help establish Antares' internal standards, tools, processes, and best practices for designing highly reliable reactor systems.
  • Drive a culture in which reliability is treated as a design requirement and continuously improved through analysis, testing, manufacturing data, and operational learning rather than evaluated only after hardware is complete.
Desired Qualifications
  • Experience with reliability engineering in nuclear, aerospace, space, automotive, energy, defense, or other safety- or mission-critical hardware industries.
  • Experience with reliability block diagrams, fault trees, failure mode and effects analysis, failure mode, effects, and criticality analysis, Weibull analysis, mean time between failures, mean time to repair, probabilistic risk assessment, availability modeling, or reliability growth methods.
  • Experience translating system-level availability or capacity factor targets into subsystem and component reliability requirements.
  • Experience with or understanding of risk-informed component classification and knowledge of 10 CFR 50.69.
  • Familiarity with mechanical and electrical design, manufacturing processes, qualification testing, material capabilities and limitations, and common hardware failure mechanisms.
  • Experience using test, field, or production data to estimate failure rates and update reliability predictions.
  • Experience driving design changes or reliability improvement plans based on quantitative reliability analysis.
  • Familiarity with statistical tools or programming languages and relevant libraries used for engineering analysis, such as Python, MATLAB, Octave, R, Minitab, SAS, NCSS, or similar.

About the company

Preparing company description.

Company Size

51-200

Company Stage

Grant

Total Funding

$757M

Headquarters

Los Angeles, California

Founded

2023

Get referred to Antares Nuclear

See people who can refer or advise you

Simplify Jobs

Simplify's Take

What believers are saying

  • Army Janus selected Antares for Fort Bragg on August 26, 2026.
  • Series C closed at $470 million on July 28, 2026, extending runway.
  • Executives target first electricity in 2027 and military deployments in 2028, compressing commercialization.

What critics are saying

  • Mark-1 still lacks electricity output; a 2027 failure kills 2028 deployment credibility.
  • Fort Bragg, Fort Hood, and Space Force programs demand flawless licensing, construction, and safety execution.
  • HALEU TRISO supply, Brayton-cycle integration, and mission-critical launch risks can stall Antares for years.

What makes Antares Nuclear unique

  • Mark-0 reached criticality June 4, 2026; Antares beat private advanced-reactor competitors.
  • TRISO-fueled, factory-produced microreactors target military bases and spacecraft, not utility-scale grids.
  • Space Force’s September 11, 2026, $161 million award validates dual-use defense-space positioning.

Help us improve and share your feedback! Did you find this helpful?

Benefits

  • Health Insurance
  • Dental Insurance
  • Vision Insurance
  • 401(k) Retirement Plan
  • Flexible Work Hours
  • Remote Work Options
  • Paid Vacation
  • Paid Sick Leave
  • Paid Holidays
  • Hybrid Work Options
  • Wellness Program
  • Mental Health Support

Growth & Insights and Company News

6 month growth

-2%

1 year growth

0%

2 year growth

9%
GlobeNewswire
Oct 8th, 2026
Exosens supports the accelerating deployment of next-generation nuclear technologies in the U.S.

Exosens supports the accelerating deployment of next-generation nuclear technologies in the U.S. October 08, 2026 12:00 ET | Source: Exosens * Key milestones achieved under the U.S. Department of Energy's Reactor Pilot Program highlight the accelerating deployment of next-generation nuclear technologies * Exosens' advanced neutron flux monitoring detectors supported successful criticality demonstrations by Antares Nuclear and Valar Atomics, underscoring the relevance of its technologies across Small Modular Reactor (SMR) applications * These achievements are expected to translate into near-term pre-series production orders and support long-term demand for Exosens' nuclear instrumentation solutions Press release, Mérignac (France), 8 October 2026 - Exosens (EXENS; FR001400Q9V2), a high-tech company focused on providing mission- and performance-critical amplification, detection and imaging technologies, today announces its contribution to two successful criticality demonstrations for next-generation nuclear reactors under the U.S. Department of Energy's Reactor Pilot Program. In August 2025, the program initially selected 11 advanced reactor projects with the goal of bringing at least three reactor designs to criticality by 4 July 2026. The program exceeded that objective, with four projects reaching this milestone by the deadline. These achievements mark a decisive step towards the commercial deployment of next-generation nuclear technologies on an accelerated timeline in the United States, particularly across SMR applications. Against this backdrop, Exosens supplied high-performance neutron detectors and related technical expertise to Antares Nuclear and Valar Atomics, the developers behind the first two reactor designs to reach criticality as part of the DOE's Reactor Pilot Program. Integrated into safety-related neutron flux monitoring systems, these advanced detectors provide the measurements required to monitor reactor power and track the approach to criticality during start-up and testing. These achievements are expected to translate into pre-series production orders in the near term and support long-term demand for Exosens' nuclear instrumentation solutions across the U.S. market. "The move towards commercial deployment of next-generation nuclear technologies is accelerating in the United States, supported by increasing demand for reliable, carbon-free power, notably to meet the unprecedented energy requirements of AI-enabled data centers. This momentum is reinforcing investment in SMR technologies and driving demand for high-performance instrumentation designed for demanding nuclear environments, creating significant long-term growth opportunities for Exosens. Already providing advanced nuclear detection solutions for seven SMR-related projects across the United States and Europe, Exosens leverages its differentiated technologies, deep nuclear expertise and industrial capabilities to address these needs and support the long-term development of the SMR market," said Jérôme Cerisier, CEO of Exosens. "Achieving criticality is a defining milestone in next-generation reactor development. The progress made by Antares Nuclear and Valar Atomics demonstrates the pace of innovation across the U.S. nuclear industry. We are proud to have supported these successful demonstrations through Exosens' advanced neutron flux monitoring technologies, and look forward to helping reactor developers as they move from first-of-a-kind testing towards safe, reliable commercial deployment," said Cyril Barre, Nuclear Instrumentation Director at Exosens. Financial calendar * 27/10/2026: 9M 2026 revenue and adjusted gross margin (before market opening). * 22/02/2027: FY 2026 results (before market opening). About Exosens Exosens is a high-tech company with more than 85 years of experience in the innovation, development, manufacturing and sale of high-end electro-optical technologies in the fields of amplification, detection and imaging. Today, it offers its customers detectors and imaging solutions such as digital cameras, ion, electron, neutron and gamma-ray detectors as well as image intensifier tubes. This enables Exosens to address complex challenges in extremely demanding environments by providing its customers with tailor-made solutions. Thanks to its sustained investment, Exosens is internationally recognized as a major innovator in optoelectronics, with production and R&D activities carried out at 13 sites across Europe and North America and more than 2,000 employees. Exosens is listed on compartment A of the regulated market of Euronext Paris (Ticker: EXENS - ISIN: FR001400Q9V2). Exosens is a member of the Euronext Tech Leaders segment and is also included in several indices, including SBF 120, CAC All-Tradable, CAC Mid 60, FTSE Total Cap and MSCI France Small Cap. For more information: www.exosens.com. Investor Relations Media Relations

World Nuclear News
Sep 18th, 2026
Antares, Centrus sign multi-year HALEU contract.

Antares, Centrus sign multi-year HALEU contract. Friday, 18 September 2026 Pre-payments under the contract will support Centrus's ongoing expansion of its uranium enrichment capacity, with deliveries of high-assay low-enriched uranium (HALEU) to support Antares' advanced reactor projects, including for space and national security missions, to begin by the end of the decade. Antares is developing modular, transportable reactors, fuelled using TRISO (tri-structural isotropic) HALEU fuel. The company's Antares 0 achieved criticality in June, becoming the first reactor under the Department of Energy's Reactor Pilot Program to achieve criticality by the deadline of 4 July set in 2025 by US President Donald Trump. The fuel for the criticality demonstration was provided by BWX Technologies, Inc. "Fuel supply is one of the practical questions every advanced reactor developer has to answer," said Antares co-founder and CEO Jordan Bramble. "This contract gives Antares a reliable, US-origin source of HALEU for the reactors we're deploying for a wide variety of defence and space customers." Centrus is already producing HALEU at its American Centrifuge Plant in Piketon, Ohio, and last year launched a multi-billion-dollar expansion including large-scale production of HALEU as well as the low-enriched uranium used in today's operating nuclear power plants. The contract is a sign that demand for HALEU is real and is accelerating, Centrus President and CEO Amir Vexler said. "Binding orders from Antares and others are supporting our expansion to commercial-scale production - an expansion that is now well under way." In August, Antares was one of five microreactor developers selected by the US Department of the Army for deployment at five Department of War installations, under the Janus programme - the next-generation nuclear power programme - which, under an Executive Order signed by Trump in May 2025, aims for operation of an Army-regulated nuclear reactor at a domestic military installation no later than 30 September 2028. Antares is to construct and operate nuclear microreactor power at Fort Bragg, North Carolina, under the programme. It has also been selected for deployment at Joint Base San Antonio, Texas, under the US Air Force's Advanced Nuclear Power for Installations programme, and is a recipient of a US Space Force Strategic Breakthrough award to demonstrate a space reactor. Certain nuclear applications in the USA, particularly those related to national security missions, require a supply of so-called unobligated enriched uranium: uranium that is free of peaceful use obligations that apply to uranium and certain technologies imported into the US under international agreements. Centrus's enrichment technology and manufacturing supply chain are of US origin, and its AC100 centrifuge design is the only deployment-ready enrichment technology capable of 'unobligated' enrichment, so the arrangement can provide Antares with fuel that could be used for a variety of national security applications. [Urenco's Magnus Mori and Antares' Tom Mancinelli pictured at World Nuclear Symposium (Image: World Nuclear Association)] Earlier this year, Antares signed a multi-year contract for the supply of HALEU with Urenco, to be produced at Urenco's HALEU enrichment facility in the UK. That facility, at the Capenhurst site in north-west England, is already being built with funding support from the UK government and is scheduled to come online in 2031. A diversity of supply sources is important to avoid over-reliance on single suppliers, Antares Head of Federal Strategy and Policy Tom Mancinelli said at a side event at World Nuclear Symposium 2026 last week. "Certainly we recognise how important it is that strategic inputs like fuel don't have any dependencies or vulnerabilities to foreign suppliers who could immediately cut something off," Mancinelli said in the event's Knowledge Zone. "It's simple to me. It comes down to supply and demand and where we have, in the case of Urenco, a demonstrated track record in enrichment - I welcome that sort of partnership, including if it's coming from Capenhurst or from (Urenco USA's enrichment plant in) New Mexico. We want to see an increase in supply from trusted Western partners who share our values, and so we think Urenco is a great fit for Antares."

Interesting Engineering
Sep 11th, 2026
Space nuclear reactor wins $161M defence contract to end 60-year orbital power gap

Louisiana-based nuclear microreactor startup Antares has secured a $161 million Strategic Breakthrough award from the US Space Force to develop nuclear power systems for future space missions. The funding represents one of the largest current US defence investments in space nuclear power. Antares will first demonstrate its R1-S reactor design on the ground before integrating it with a spacecraft for flight certification. The company plans to begin testing its Mark-1 reactor in 2027, which will operate for over six months during the test campaign. The startup achieved a significant milestone in June when its Mark-0 microreactor reached initial criticality at Idaho National Laboratory, making Antares the first private company to achieve advanced-reactor criticality under the Department of Energy's Reactor Pilot Program. The US has not operated a nuclear reactor in space since NASA's SNAP-10A mission in 1965.

Citybiz
Sep 11th, 2026
Antares wins $161 million Space Force award for nuclear reactor demonstration.

Antares wins $161 million Space Force award for nuclear reactor demonstration. September 11, 2026 Rendering of a nuclear-powered spacecraft in Earth orbit Antares has been selected for a $161 million Strategic Breakthrough award to demonstrate nuclear power technology for space, giving the nuclear energy company a path to test its R1-S reactor on the ground and integrate the system with a spacecraft ahead of flight certification and launch. The award was made through the Office of the Assistant Secretary of the Air Force for Space Acquisition and Integration and represents the largest Department of War award for space nuclear power to date, according to Antares. Under the program, Antares will conduct a nuclear ground demonstration of its R1-S system before integrating the reactor with a spacecraft for flight certification. The work moves the company's compact fission technology toward an operational space mission rather than limiting development to reactor testing. Antares will also use Mark-1, its electricity-producing reactor, to power an operational ground-to-space asset. Testing of Mark-1 is scheduled for 2027, creating another step in validating how the company's reactor and power-conversion technologies perform as an integrated energy system. "This partnership with the Space Force turns that long-held vision into a codified space mission," CEO and co-founder Jordan Bramble said. "Fission will unlock strategic capabilities that are impossible today." The program addresses one of the central infrastructure constraints for more power-intensive spacecraft: generating reliable electricity while maintaining sufficient propulsion capacity for maneuvering. Nuclear fission could provide continuous power for systems with heavier computing requirements and other high-demand payloads without depending on conventional spacecraft power architectures alone. Antares is targeting applications including advanced computing, directed-energy systems and electromagnetic warfare. The company also sees nuclear power as a way to reduce propulsion-related operational constraints, potentially allowing spacecraft to conduct more dynamic maneuvers while maintaining power for onboard systems. The award builds on a reactor milestone Antares reached earlier this year. On June 4, 2026, its Mark-0 microreactor achieved initial criticality at Idaho National Laboratory under Department of Energy authorization. Antares said the milestone made it the first private company to bring an advanced reactor to criticality through the DOE Reactor Pilot Program. The next stage centers on producing usable electricity. Antares plans to operate its Mark-1 reactor for more than six months in 2027, integrating it with the company's nitrogen closed Brayton cycle power-conversion system. That configuration is designed to move development beyond reactor physics and demonstrate an integrated system capable of converting reactor heat into electricity. Successfully coupling the reactor with power conversion is an important operational requirement for both terrestrial and space applications. The company's development sequence moves from Mark-0 criticality to extended Mark-1 electricity production, followed by the R1-S ground demonstration and spacecraft integration required for a potential flight mission. The Strategic Breakthrough program also aligns with federal plans to accelerate deployment of nuclear power beyond Earth. Antares said the award supports goals established by Executive Order 14369, "Ensuring American Space Superiority," and the National Initiative for American Space Nuclear Power established through NSTM-3. Those policies call for nuclear reactors to be launched into space as early as 2028 and deployed on the lunar surface by 2030. Founded in 2023, Antares is developing compact nuclear microreactors for defense and space applications. The company has raised more than $600 million and expects initial production deployments at U.S. military installations beginning in 2028. Antares operates facilities in Torrance, California; Idaho Falls, Idaho; and Aiken, South Carolina. The $161 million award adds a dedicated space mission to a development program that is now moving from reactor criticality toward electricity generation, spacecraft integration and eventual deployment.

Payload Space
Sep 11th, 2026
Antares wins $161M award for space nuclear power.

Antares wins $161M award for space nuclear power. Friday September 11, 2026 Waxing Crescent Payload in your inbox. In-depth research, exclusive data, and expert analysis on the business and policy of space. Get ahead of the competition.