Spacecraft Thermal Engineer

Our client is a growing engineering and technology company developing advanced systems for challenging and high‑performance environments. Their multidisciplinary team brings together engineers, designers, and technical specialists to develop innovative products from concept through to testing and deployment. They operate in a fast‑paced environment where engineers have the opportunity to take ownership, work across disciplines, and contribute directly to the development of new technology. You'll have the opportunity to work on challenging engineering projects, develop your technical skills, and see your work progress from analysis and design through to testing and real‑world application. Working closely with engineers across mechanical, electrical, systems, manufacturing, and test functions, you will contribute throughout the product development lifecycle — from early design and analysis through to testing and validation.

- Develop, run, and maintain thermal models for systems, subsystems, and components.
- Perform thermal analysis across a range of operating and environmental conditions.
- Define thermal cases and assumptions that support engineering and design decisions.
- Support the design and sizing of active and passive thermal control solutions.
- Perform first‑principles calculations, hand calculations, and first‑order analysis to validate results.
- Conduct thermal trade studies considering performance, mass, power, cost, manufacturability, and operational requirements.
- Support thermal testing and validation activities and correlate analysis with test results.
- Prepare technical reports, analysis documentation, design notes, and review materials.
- Work closely with multidisciplinary engineering teams to resolve thermal issues and support system‑level decisions.
- Develop and improve thermal analysis tools, models, databases, and post‑processing workflows.
- Contribute to continuous improvement of engineering methods, processes, and tools.

01st October, 2026

About You

- A hands‑on and practical engineering mindset.
- Strong analytical and problem‑solving skills.
- An ability to turn analysis and simulation results into practical engineering solutions.
- A collaborative approach and confidence working across multiple engineering disciplines.
- The ability to work independently, take ownership, and make decisions in a fast‑moving environment.
- A willingness to learn and work across areas outside your immediate technical discipline.

Proven Experience

- Bachelor's degree or higher in Mechanical, Aerospace, Space Systems, or related engineering discipline.
- 2+ years of experience in thermal analysis and/or thermal design.
- Hands‑on experience developing and running thermal models using an industry‑standard tool such as Thermal Desktop, Systema/Thermica, ESATAN‑TMS, NX Space Systems Thermal or equivalent.
- Understanding of thermal analysis principles and environmental factors that influence thermal performance.
- Ability to perform first‑principles calculations and independently validate model results.
- Understanding of passive and active thermal control methods, including selection, sizing, and integration considerations.
- Strong systems‑thinking and multidisciplinary engineering skills.





Desirable Experience

- Familiarity with relevant engineering standards such as ECSS, NASA, or MIL‑STD.
- Experience with thermal testing and test correlation.
- Experience translating operating modes, mission profiles, or system requirements into thermal analysis inputs.
- Experience with materials, coatings, radiation, contamination, outgassing, or other environmental considerations.
- Experience with fluids and/or propulsion systems.
- Experience using Python for analysis, data processing, automation, or reporting.
- Understanding of systems engineering, requirements management, verification, and validation.
- Experience working in a start‑up, New‑Space, or fast‑paced product development environment.

You must have working rights in Australia to be eligible for this position.

Our mission is to safeguard critical space infrastructure by providing the first integrated security platform to see threats, decide fast and respond at scale. Where spacecraft have traditionally been costly, slow to produce and require extensive effort to coordinate, SMC is developing systems that are produced at scale and operated with human‑on‑the‑loop autonomy to drastically reduce the cost and complexity of orbital operations. As space becomes more congested and contested, the satellites that underpin modern life are increasingly exposed. We are developing the vehicles and software to protect them, working with commercial operators and government agencies across allied nations. The Optimus Viper Rapid Response Vehicle delivers genuine mission capability at a fraction of conventional spacecraft cost. Solstice OS, our AI‑driven command and control platform, fuses space domain awareness data and automates mission planning and vehicle coordination, allowing smaller teams to manage larger constellations and respond to emerging situations in seconds rather than hours.

Why Join Us

We're a start‑up. Things move fast, resources are lean, and we're building as we go.

What we offer is opportunity: to learn at speed, grow with the company, and leave your fingerprints on something that's never been done before. At Space Machines Company, engineers, innovators, and problem‑solvers join forces to push the limits of what's possible.

If you want to build technology designed to protect and power humanity's future in space and see your work make a visible impact. This is where you'll do it.

How We Work

We are builders first. We approach every challenge through a cycle of design, build, test, and refine, making ideas real, learning from results, and improving with each iteration.

We challenge assumptions to make sure we're solving the right problems, and we strengthen our solutions through collaboration and feedback.

We use process where it adds value and set it aside where it slows us down. There are a lot of firsts here, and we meet them with curiosity and courage.





We win as one team.

The Role

As our Spacecraft Thermal Engineer, you will work alongside the Thermal and Mission Systems Lead to analyse, design, and validate the thermal control systems that keep Optimus Viper operating across harsh orbital regimes, from LEO to GEO and beyond. You'll ensure our vehicles not only survive but perform through every mission phase, from launch through end‑of‑life.

You’ll spend your time on real projects from the beginning: building thermal models, running analysis cases at varying levels of fidelity, and translating results into clear recommendations that guide design decisions, while also supporting thermal test campaigns, design reviews, and close collaboration with avionics, structures, propulsion, power, GNC, manufacturing, and AIT.

This is a unique opportunity to contribute to the fast‑paced design, build, and testing of a Rendezvous and Proximity Operations (RPO) capable spacecraft.

Key Responsibilities

- Thermal Analysis – Develop, run, and maintain thermal models (GMM/TMM) of spacecraft, subsystems, and equipment using industry‑standard tools (such as Thermal Desktop, Systema/Thermica, ESATAN‑TMS, or equivalent). You will define hot, cold, and edge cases that drive the design, and correlate models against test and flight data.
- Thermal Design – Support the design and sizing of active and passive thermal control solutions. You will translate analysis into practical hardware recommendations the team can build against.
- Rapid Iteration – Execute hand calculations, spreadsheet models, and Python first‑order analysis grounded in first principles. You will apply the right level of fidelity for the question at hand and turn analysis around fast enough to keep pace with fast design cycles.
- Trade Studies & Recommendations – Conduct trade‑off studies on thermal architecture, balancing thermal performance against mass, power, cost, manufacturability, operational constraints and schedule. You will present key assumptions, problems, results, and conclusions to the Thermal and Mission Systems Lead and wider team to guide real design decisions.
- Test & Validation – Support and execute thermal testing of our spacecraft and equipment. You will see your work through from analysis to chamber and get real feedback on how the design performs.
- Documentation & Reviews – Produce explicit thermal analysis reports, design notes, verification evidence, and review material. You will support internal and external technical reviews, including reviews with customers and partners.
- Tools & Infrastructure – Develop and maintain internal thermal analysis tools, material property databases, model templates, and post‑processing workflows. You'll help guide the tools and processes the team uses to improve speed, consistency, and traceability.

Benefits

- Competitive salary – Fair pay for hard work. Commensurate with experience and the impact you'll have.
- Meaningful equity (ESOP) – Real ownership stake. Stock options that matter because you're joining early enough for them to matter. If we win, you win.
- Actual leave – Annual leave plus personal/sick days. Because even warriors need to recover.
- Public holidays – All of them.

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