Sr. Spacecraft Thermal Engineer at Observable Space (Los Angeles, CA)Sr. Spacecraft Thermal Engineer

At Observable Space, we're redefining how humanity observes and connects with the universe. We're a vertically integrated, high-growth, space technology company building industry-leading precision optics platforms for Earth and in space. Our systems are trusted by thousands of customers, including NASA, JPL, SpaceX, Boeing, RTX, the US Space Force and the U.S. Department of War, leading research institutions and international partners. We combine precision opto-mechanical hardware, embedded compute, cloud orchestration, and developer-friendly APIs into world class products at scale with in-house manufacturing. From advanced ground stations, on-orbit sensor suites, free space optical lasercom, to distributed compute platforms, we deliver the foundational systems enabling continuous, real-time navigation, observation, and communication in space. Observable Space is backed by top-tier institutional investors including Lux Capital, Upfront Ventures, RTX Ventures, Detroit Venture Partners and Embedded Ventures. To learn more, visit observable.space.

We are seeking a highly-motivated and hands-on Senior Spacecraft Thermal Engineer to join our growing team. In this role, you’ll design and develop thermal control systems for telescope platforms and spacecraft. You’ll work with a multidisciplinary team of optical, electrical, mechanical, and software engineers to ensure thermal stability and performance for ground-based and potential future space-based deployment.

• Design and optimize thermal control systems for spacecraft and telescope platforms (e.g., radiators, heaters, insulation, thermal straps, and enclosures).
• Develop thermal models and perform detailed thermal analysis (steady-state and transient) across operational environments.
• Perform STOP analysis (Structural, Thermal, Optical Performance) to verify system-level thermal stability and its impact on optical performance.
• Conduct FEA simulations for thermal, structural, and environmental conditions.
• Collaborate with optics, mechanical, and electrical teams to ensure proper thermal integration with imaging, tracking, and sensing subsystems.
• Define thermal requirements, margins, and verification strategies for system and subsystem performance.
• Support environmental testing, including thermal vacuum (TVAC), thermal cycling, and validation of thermal models.
• Support the full product lifecycle, from concept design and prototyping to testing and production.
• Participate in and contribute to design reviews (PDR, CDR, etc.) and internal documentation.
• Provide engineering support during fabrication, integration, QC, and system validation.

• Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, or equivalent.
• 5+ years of experience in thermal engineering for aerospace or high-performance systems.
• Strong understanding of heat transfer fundamentals (conduction, convection, radiation).
• Experience with thermal analysis tools (e.g., Thermal Desktop, SINDA/FLUINT, ANSYS, or similar).
• Experience developing and validating thermal models for complex systems.
• Effective communicator and collaborator.
• Demonstrated passion for aerospace or observational technologies.

• Experience with spacecraft thermal control systems and space environments (LEO, GEO, or deep space).
• Understanding of FEA (ANSYS, Nastran, etc.), tolerance analysis, and DFM principles.
• Experience with thermal vacuum (TVAC) testing, thermal cycling, and model correlation.
• Grasp of materials, coatings, surface properties, and thermal interface design.
• Understanding of system engineering workflows, interface control documents, and verification processes.
• Experience working in fast-paced, early-stage or startup environments.
• Basic scripting or automation (Python, MATLAB) for thermal modeling or data analysis.

Competitive Compensation – A salary package aligned with industry standards and your experience. Equity Opportunities – Take part in our success with stock options. Flexible Work Environment – Enjoy working from our office or in a hybrid work setup with the flexibility to work remotely part of the week. We require a minimum of 3 days per week in our office to support collaboration and team culture. (LA Office only) Unlimited PTO (exempt only) – Take the time you need with our flexible, trust-based vacation policy, including paid holidays. We encourage everyone to rest, recharge, and take care of themselves. Health & Wellness – Comprehensive medical, dental, and vision coverage with 100% of the premium paid by the employer for employees. Cutting-Edge Tools – Get access to the latest hardware and software you need to do your best work. Mission-Driven Culture – Be part of a team working on meaningful challenges with real-world impact. Inclusive Team – We foster a supportive and diverse workplace where all voices are valued.

Observable Space is an equal opportunity employer. We consider all qualified applicants for employment without regard to race, color, religion, sex, pregnancy, sexual orientation, gender identity or expression, national origin, ancestry, age, disability, genetic information, marital status, veteran or military status, or any other characteristic protected by applicable federal, state, or local law.