Radiation Effects Engineer - Modeling

Astranis builds advanced satellites for high orbits, expanding humanity’s reach into the solar system. Today Astranis satellites provide dedicated, secure networks to highly-sophisticated customers across the globe – large enterprises, sovereign governments, and the US military. With five satellites on orbit and many more set to launch soon, the company is servicing a backlog of more than $1 billion of commercial contracts. Astranis is the preferred satellite communications partner for buyers with stringent requirements for uptime, data security, network visibility, and customization. Astranis has raised over $1.2 billion from some of the world’s best investors, including Andreessen Horowitz, Baillie Gifford, Blackrock, Fidelity, Franklin Templeton, and Snowpoint, and employs a team of 500 engineers and entrepreneurs. Astranis designs, builds, and operates its satellites out of its 153,000 sq. ft. headquarters in Northern California, USA. Radiation Effects Engineer - Modeling Astranis is bridging the digital divide by building and operating the next generation of smaller, lower-cost geostationary telecommunications satellites. As a Radiation Effects Engineer focused on modeling and theory, you will own the analytical definition of our spacecraft's radiation and charging environments, transforming physical theory into actionable design constraints. You will serve as an authority on radiation transport, orbital environment propagation, and charging physics. This modeling will help guide our hardware, mechanical, and systems teams in PCB design. Your work will directly define our engineering posture, allowing us to safely navigate geostationary orbit (GEO) and other space environments. Role • Own the analytical model of the geostationary (GEO) radiation environment, modeling trapped particle populations (AP8/AP9, AE8/AE9), solar proton fluences (Sapphire), and galactic cosmic rays (CREME96) • Perform high-fidelity 3D Monte Carlo and sector-analysis radiation transport simulations using FASTRAD against complex spacecraft CAD assemblies to generate local, component-level dose-depth curves • Lead analytical studies on spacecraft charging, including surface charging (using NASCAP-2k or SPIS-SC) and internal charging (using FASTRAD internal charging calculations or SPIS-IC) to prevent electrostatic discharge (ESD) risks • Develop, scale, and maintain Python-based pipelines to process, analyze, and visualize transport simulation datasets, automating the generation of spacecraft-wide dose budgets • Translate complex simulation data into actionable engineering guidance for shielding allocation, material selection, and electrical grounding architectures Requirements • Bachelor of Science degree in Nuclear Engineering, Physics, Electrical Engineering, or equivalent. • 2+ years of industry experience using radiation environment tools such as OMERE or SPENVIS and transport tools such as FASTRAD, Geant4, or MCNP • Solid theoretical foundation in radiation interaction with matter, including ionization, non-ionizing energy loss, charge deposition, and secondary bremsstrahlung generation • Experience modeling spacecraft charging physics and electric field buildup in dielectrics • Proficiency in Python for mathematical post-processing, data scraping, and modeling automation • High-degree of ownership and technical depth; ability to evaluate complex system trade-offs with sparse initial data Bonus • Master of Science or PhD in Nuclear Engineering, Nuclear Physics, or equivalent with a research focus on space radiation environments or spacecraft charging phenomena • Deep knowledge of deep dielectric charging failure mechanisms (ECEMP) and industry standard mitigations (grounding straps, conductive coatings, slot-venting geometries) • Familiarity with the ISO 11221 spacecraft charging standard or MIL-STD-883 Test Method 1019 What we offer: All our positions offer a compensation package that includes equity and robust benefits. Base pay is just one component of Astranis’s total rewards package. Your compensation also includes a significant equity package via incentive stock options, high-quality company-subsidized healthcare, disability and life insurance, 401(k) retirement planning, flexible PTO, and free on-site catered meals. Astranis pay ranges are informed and defined through professional-grade salary surveys and compensation data sources. The actual base salary offered to a successful candidate will additionally be influenced by a variety of factors including experience, credentials & certifications, educational attainment, skill level requirements, and the level and scope of the position. Base Salary $120,000—$145,000 USD U.S. Citizenship, Lawful Permanent Residency, or Refugee/Asylee Status Required (To comply with U.S. Government space technology export regulations, applicant must be a U.S. citizen, lawful permanent resident of the United States, or other protected individual as defined by 8 U.S.C. 1324b(a)(3)) Our mission and products are built for everyone, regardless of gender, race, creed, or background. We believe in a diverse and inclusive workplace, and we invite all people to join our team and bring their unique perspectives to make us stronger. Astranis SMS Terms of Service • Recruiting Updates: By opting in, you agree to receive SMS updates, interview coordination, and recruiting communications from Astranis Space Technologies Corp. • Opt-Out: You can cancel this service at any time by replying STOP. 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