Systems Engineer, Spacecraft Design & Simulation

<div class="content-intro"><p>At Vast, our mission is to contribute to a future where billions of people are living and thriving in space. Vast is developing next-generation space stations to ensure a continuous human presence in space for America and its allies, enabling advanced microgravity research and manufacturing, and unlocking a new space economy for government, corporate, and private customers. Using an incremental, hardware-rich and low-cost approach, Vast is rapidly developing its multi-module Haven Station. Haven Demo’s 2025 success made Vast the only operational commercial space station company to fly and operate its own spacecraft. Next, Haven-1 is expected to become the world’s first commercial space station when it launches, followed by additional Haven modules to enable permanent human presence by 2030. Our team is all-in, committed to executing our mission safely and on time. If you want to work with the most talented people on Earth furthering space exploration for humanity, come join us.</p></div><p>Vast is seeking a <strong>Systems Engineer, Spacecraft Design & Simulation</strong> to own the spacecraft simulation toolchain that is the foundation of our mission factory — the software infrastructure that will enable us to scale from our first 10-satellite demo launch to hundreds of spacecraft per year. </p>
<p>This will be a <strong>full-time</strong>, <strong>exempt</strong> position located in our <strong>Long Beach</strong> location. </p>
<p><strong>About the role:</strong></p>
<p>We're building a mission factory — software infrastructure that dramatically reduces the time from customer contract to payload on orbit. The foundation is a simulation and digital twin toolchain that serves as the primary engineering record. Requirements, budgets, design parameters, and trade study results all live in this toolchain. It includes spacecraft power/thermal/ADCS simulation, orbital constellation analysis, communications link budgets, and actuator trade studies. This is model-based systems engineering as it should work — requirements, budgets, and design parameters live in executable models that compute and validate, not in static documents. A working prototype exists today — you'll evaluate it, determine whether to extend it or redesign it, and own the toolchain as we scale from our first 10-satellite demo launch to hundreds of spacecraft per year.</p>
<p>This is a spacecraft systems engineering role, not a software engineering role. You define the governing equations, boundary conditions, and expected behavior for each model. You build and maintain a rigorous validation suite — hand calculations, independent tool cross-checks, and edge case analysis — that serves as the quality gate for every change. We use AI code generation tools to accelerate implementation, but the engineering judgment, validation methodology, and physics expertise are yours.</p>
<p><strong>Responsibilities: </strong></p>
<ul>
<li>Own and evolve the spacecraft design, simulation, and digital twin toolchain — power, thermal, ADCS, orbital mechanics, constellation coverage, link budgets, mass and design margin tracking</li>
<li>Make the toolchain the hub of the engineering organization — every discipline (thermal, GNC, power, structures) should be able to run trade studies and assess design changes quickly as the program evolves</li>
<li>Drive design trades and architecture decisions through analysis — your models are how the team knows whether the power budget closes, whether the thermal architecture works, and whether we meet customer requirements</li>
<li>Enable rapid iteration as customer requirements and the design evolve — the toolchain must keep pace with the program so engineers can assess impact immediately, not wait weeks for analysis</li>
<li>Maintain the digital twin as the program's engineering record — requirements, budgets, design parameters, and trade study results live here</li>
<li>Build and maintain a rigorous validation suite — hand calculations, independent tool cross-checks, edge case analysis, and regression testing for every physics model</li>
<li>Train and support the engineering team so they can self-serve on trade studies and analysis</li>
</ul>
<p><strong>Minimum Qualifications:</strong></p>
<ul>
<li>Bachelor's degree in Aerospace Engineering, Mechanical Engineering, Electrical Engineering, Physics, or a related technical discipline</li>
<li>4+ years of spacecraft systems engineering or mission analysis experience</li>
<li>Spacecraft systems engineer with broad subsystem knowledge — you understand power, thermal, ADCS, and orbital mechanics well enough to catch errors in a simulation</li>
<li>Strong analytical skills — you can set up a hand calculation for a thermal equilibrium problem, a power budget across an orbit, or a pointing error budget</li>
<li>Rigorous validation mindset — you're the person who asks “how do we know this is right?” and builds the test to prove it</li>
<li>Comfortable with AI-assisted development workflows</li>
<li>Generalist background — prior experience at a small-sat company, research lab, or mission design role where you touched multiple subsystems</li>
<li>Cross-functional collaboration skills — you'll work with every discipline lead to capture their domain knowledge and translate it into validated models</li>
<li>Comfortable reading and reviewing code — you don't need a software engineering background, but you should be able to understand what code is doing and catch errors</li>
</ul>
<p><strong>Preferred Skills & Experience:</strong></p>
<ul>
<li>Able to obtain a security clearance</li>
<li>Experience building or maintaining spacecraft simulation tools</li>
<li>Familiarity with orbital mechanics (Kepler solver, J2 perturbations, eclipse geometry)</li>
<li>Familiarity with CMG dynamics, quaternion attitude propagation</li>
<li>Experience with data visualization tools or libraries</li>
<li>Demonstrated use of AI-assisted code generation tools on an engineering project — show us what you built</li>
<li>Requirements management and verification experience on a spacecraft mission</li>
<li>Experience with MBSE tools or model-based development methodologies</li>
<li>Experience scaling engineering tools or analysis workflows across a growing team</li>
<li>Experience developing validation and verification test suites for engineering tools</li>
</ul><div class="content-pay-transparency"><div class="pay-input"><div class="title">Pay Range: California</div><div class="pay-range"><span>$112,340</span><span class="divider">—</span><span>$159,468 USD</span></div></div></div><div class="content-conclusion"><p style="line-height: 1;"><strong>COMPENSATION AND BENEFITS<br></strong><br>Base salary will vary depending on job-related knowledge, education, skills, experience, business needs, and market demand. Salary is just one component of our comprehensive compensation package. Full-time employees also receive company equity, as well as access to a full suite of compelling benefits and perks, including: medical, dental, and vision coverage for employees and dependents, generous paid time off; up to 20+ days of vacation for exempt staff and up to 10+ days of vacation for non-exempt staff with the ability to cash-out unused vacation annually, paid parental leave, short and long-term disability insurance, life insurance, access to a 401(k) retirement plan, ClassPass credits, personalized mental healthcare through Spring Health, and other discounts and perks. We also take pride in offering exceptional food perks, with snacks, drip coffee & onsite barista, cold drinks, and dinner meals remaining free of charge, and lunch subsidized as part of Vast’s ongoing commitment to providing high-quality meals for employees.</p>
<p style="line-height: 1;"><strong><br>U.S. EXPORT CONTROL COMPLIANCE STATUS<br><br></strong>The person hired will have access to information and items subject to U.S. export controls, and therefore, must either be a “U.S. person” as defined by <a href="https://www.ecfr.gov/current/title-22/section-120.62">22 C.F.R. § 120.62</a> or otherwise eligible for deemed export licensing. This status includes U.S. citizens, U.S. nationals, lawful permanent residents (green card holders), and asylees and refugees with such status granted, not pending.<br><br></p>
<p style="line-height: 1;"><strong>EQUAL OPPORTUNITY</strong><br><br>Vast is an Equal Opportunity Employer; employment with Vast is governed on the basis of merit, competence and qualifications and will not be influenced in any manner by 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.</p></div>