Skip to content

Spacecraft Thermal Engineer (Mid-Career) – Millennium Space Systems

El Segundo, California; and other locations
Full Time On-site

Summary

Job Description

Job Description

At Boeing, we innovate and collaborate to make the world a better place. We’re committed to fostering an environment for every teammate that’s welcoming, respectful and inclusive, with great opportunity for professional growth. Find your future with us.

Job Description

Millennium Space Systems, a part of Boeing Defense, Space and Security (BDS), is a fast, agile small satellite company focused on national security space. Our missions have direct impact to global security, like missile warning and Earth observation.

Our team is curious, bold and innovative. We take risks, innovate and explore new techniques and technologies. We influence change because we challenge the status quo. And when we watch our satellites launch, we know each one of us made it happen.

Job Summary

As a Mission Operations Engineer, you will be the lead technical authority for Millennium’s on-orbit spacecraft.  Your work will encompass the entire spacecraft mission life cycle, from the proposal phase to spacecraft and mission design, through space vehicle integration and test, and culminating with launch and on-orbit operations.  You will be responsible for all facets of the mission design, including definition of operational concepts, development of on-orbit procedures, and innovation of advanced methods of spacecraft operation unique to each space mission.  Mission Operations requires composure in high-pressure situations, in-depth knowledge of both the space vehicles and ground segment, and an ability to respond to anomalous scenarios in real-time.  You will be directly responsible for Millennium’s critical on-orbit assets. 

This position’s internal job code is Systems Engineer. Our team is currently hiring for levels 3-4.

Job SummaryThermal Engineers support the Spacecraft Development Program Managers and Chief Systems Engineer through the development of all spacecraft thermal system configurations, designs, analyses, testing, and flight operations. Spacecraft thermal subsystem elements includes all passive and active means of controlling the satellite’s system, subsystem, and component environments within both operating and survival limits during all pertinent system lifetime activities. Thermal engineers also have the opportunity to support MLI blanket design, fabrication, and installation.

This position’s internal job code is Mechanical System Design & Analysis Engineer. Our team is currently hiring for a level 3-4. 

Responsibilities

  • Perform spacecraft thermal design and analyses at the board, component, subsystem, and system level 
  • Develop systems and spacecraft element thermal models to predict thermal loads, impacts, and temperature margins to support system design
  • Brief design and analysis materials to program managers, customers, and/or sponsors
  • Identify all materials, processes, and facilities to achieve a qualified spacecraft thermal design and operation
  • Assists in proposal and new business development efforts
  • Support thermal verification testing on spacecraft systems and components including test design, test conduct, data reduction, analysis, and reporting 
  • Support the development of tools to aide in conceptual designs and post-processing analysis
  • Potential to cross-train with MLI team for hands-on support

This position is expected to be 100% onsite. The selected candidate will be required to work onsite at one of the listed location options. 

Security Clearance and Export Control Requirements

This position must meet Export Control compliance requirements, therefore a “US Person” as defined by 22 C.F.R. § 120.15 is required. “US Person” includes US Citizen, lawful permanent resident, refugee, or asylee.

Minimum Qualifications

  • Bachelor’s degree in Mechanical Engineering, Aerospace Engineering, Physics, or other relevant fields
  • 2 or more years of experience in the design, development, analysis, implementation, testing, and/or operation of spacecraft thermal systems or other related complex thermal systems
  • Proficiency with thermal analysis tools (e.g. Thermal Desktop, SINDA/FLUINT, ANSYS, Thermica)
  • Ability to obtain and maintain a TS/SCI Security Clearance 

Preferred Qualifications

  • Active TS/SCI Clearance

Conflict of Interest:

Successful candidates for this job must satisfy the Company’s Conflict of Interest (COI) assessment process

Drug Free Workplace:

Millennium Space Systems, a Boeing Company, is a Drug Free Workplace (DFW) where post offer applicants and employees are subject to testing for marijuana, cocaine, opioids, amphetamines, PCP, and alcohol when criteria is met as outlined in our policies.

Shift:

  • This role will be on 1st

Total Rewards:

At Millennium Space Systems, a Boeing Company, we strive to deliver a Total Rewards package that will attract, engage and retain the top talent.  Elements of the Total Rewards package include competitive base pay and variable compensation opportunities.  

Millennium Space Systems also provides eligible employees with an opportunity to enroll in a variety of benefit programs, generally including health insurance, flexible spending accounts, health savings accounts, retirement savings plans, life and disability insurance programs, and a number of programs that provide for both paid and unpaid time away from work.  

The specific programs and options available to any given employee may vary depending on eligibility factors such as geographic location, date of hire, and the applicability of collective bargaining agreements.

Pay is based upon candidate experience and qualifications, as well as market and business considerations.

Summary Pay-Range

  • Level 3: $102,000 - $150,000 
  • Level 4: $124,100 - $182,500

Millennium is DDTC-registered, ITAR-compliant Company. This position is located at a facility that requires special access. Applicants MUST be U.S. citizens and eligible for a security clearance. Additionally, applicants must be willing to apply for and maintain a security clearance. We encourage all interested candidates to apply for any open position for which they feel they are qualified.

Applications for this position will be accepted until Jun. 22, 2026

Export Control Requirements:

This position must meet U.S. export control compliance requirements. To meet U.S. export control compliance requirements, a “U.S. Person” as defined by 22 C.F.R. §120.62 is required. “U.S. Person” includes U.S. Citizen, U.S. National, lawful permanent resident, refugee, or asylee.

Export Control Details:

US based job, US Person required

Education

Bachelor's Degree or Equivalent Required

Relocation

Relocation assistance is not a negotiable benefit for this position.

Security Clearance

This position requires the ability to obtain a U.S. Security Clearance for which the U.S. Government requires U.S. Citizenship. An interim and/or final U.S. Secret Clearance Post-Start is required.

Visa Sponsorship

Employer will not sponsor applicants for employment visa status.

Shift

This position is for 1st shift

Equal Opportunity Employer:

Boeing is an Equal Opportunity Employer. Employment decisions are made without regard to race, color, religion, national origin, gender, sexual orientation, gender identity, age, physical or mental disability, genetic factors, military/veteran status or other characteristics protected by law.

About Boeing

Boeing

Boeing is one of the largest aerospace and defense companies in the world, supporting critical military, commercial aviation, space, and national security missions. With a long history of innovation, Boeing develops advanced aircraft, satellites, autonomous systems, defense platforms, and space technologies used by the U.S. military and allied partners worldwide. The company plays a major role in programs ranging from fighter aircraft and military helicopters to missile defense, space systems, and next-generation aviation technologies.

For job seekers, Boeing offers opportunities across nearly every area of aerospace and defense, including engineering, software development, cybersecurity, manufacturing, supply chain, program management, aviation maintenance, and defense operations. The company is especially attractive to veterans, cleared professionals, engineers, and candidates looking for mission-driven work with strong long-term career growth. Boeing also offers extensive training, leadership development, and opportunities to work on some of the most recognized aerospace programs in the world.

Unlike smaller defense firms focused on a single capability, Boeing provides employees exposure to a broad mix of commercial and defense technologies. Teams contribute to programs involving military aircraft, autonomous systems, satellites, advanced manufacturing, AI, and next-generation aerospace innovation. Employees often value the combination of large-scale engineering challenges, global impact, and the stability of a major industry leader.

As defense modernization, commercial aviation, and space investment continue to grow, Boeing remains one of the most recognized employers in aerospace and government contracting. For professionals seeking a mission-focused career with strong benefits, technical growth, and opportunities to work on world-changing technologies, Boeing continues to stand out as a leading destination in aerospace and defense.

Go to company profile