Principal Mechanical Engineer I

Austin, TX
Engineering – Mechanical /
Full-time /
Please Note: To conform with the United States Government Space Technology Export Regulations, the applicant must be a U.S. citizen, lawful permanent resident of the U.S., conditional resident, asylee or refugee (protected individuals as defined by 8 U.S.C. 1324b(a)(3)), or eligible to obtain the required authorizations from the U.S. Department of State.

At CesiumAstro, we are developers and pioneers of out-of-the-box communication systems for satellites, UAVs, launch vehicles, and other space and airborne platforms. We take pride in our dynamic and cross-functional work environment, which allows us to learn, develop, and engage across our organization. If you are looking for hands-on, interactive, and autonomous work, CesiumAstro is the place for you. We are actively seeking passionate, collaborative, energetic, and forward-thinking individuals to join our team.

We are looking to add a Principal Mechanical Engineer I to our Mechanical Engineering team. If you are great at what you do, enjoy working in a startup environment, and are passionate about developing space hardware for leading-edge communications satellites, we would like to hear from you. 

 In this position, you will be responsible for mechanical design aspects of Cesium phased array antennas, subsystems, and interfaces through all phases of the development process. The ideal candidate will be versatile and proficient in mechanical analysis, electronics packaging, computer-aided design (CAD), mechanical interfaces, thermal architecture, spacecraft propulsion, deployable and actuated structures, and environmental qualification of spacecraft antennas and payloads. You will be responsible for mechanical designs from concept through space flight including requirements definition, architecture trades and block diagrams, analysis, manufacturing, testing, qualification, and in-orbit support. 

The successful candidate will also present engineering design review materials to our customers and executive team, as well as participate in proposal-writing efforts. As such, excellent written and verbal communication skills are required. 


    • Bachelor of Science (BS) in Mechanical or Aerospace Engineering from an accredited university or institution 
    • Minimum of 9 years of experience in space antenna and payload mechanical engineering to include electronics packaging, thermal, shock, vibration, stress dynamics, and cost. A Master’s degree may count as two years of experience. 
    • Experience in conducting architectural trade studies including parametric and first-order cost and physical analysis. 
    • Experience with professional mechanical and FEA CAD tools, such as Ansys Mechanical, SolidWorks Simulation, and Thermal Desktop 
    • Experience with CNC manufacturing and GD&T 
    • Experience with advanced aerospace manufacturing and materials including sandwich panels and carbon composites, OR experience with high-reliability deployment mechanisms for space applications (including deployment, HDRMs, power delivery, etc.).
    • Proficiency in detailed mechanical design (3D CAD, drawings, etc.) 
    • Experience designing and manufacturing mechanisms and mechanical actuators. 
    • Experience with EMI/EMC mitigation techniques 
    • Familiarity with satellite thermal architectures including heat pipes, phase change materials, contact resistance, and surface finishes as well as fundamental understandings of orbital thermal control in a LEO environment. 
    • Familiarity with launch and LEO environments (thermal, shock, vibe, radiation, etc.) 
    • Familiarity with design for test, manufacturability, assembly, and reliability 
    • Excellent written and verbal communication skills 


    • Python, C++, or other programming languages. 
    • Experience with large, deployable antenna arrays which drive your vision for the next generation of on-orbit communications and sensor arrays.
    • Robotics and control systems experience. 
    • PCBA experience.
CesiumAstro considers several factors when extending an offer, including but not limited to, the role and associated responsibilities, a candidate’s work experience, education/training, and key skills. Full-time employment offers include company stock options and a generous benefits package featuring health, dental, vision, HSA, FSA, life and retirement plans. 
CesiumAstro, Inc. is an Equal Opportunity/Affirmative Action employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, sex including sexual orientation and gender identity, national origin, disability, protected Veteran Status, or any other characteristic protected by applicable federal, state, or local law.