Mariam Al Hammadi spent about three minutes in front of a small glass window, observing the operation of an electric motor in a vacuum chamber where a simulated space environment was recreated. Xenon was fed into the motor, and after a signal was sent, the system began to operate. Al Hammadi recalls that observing the blue glow emanating from the motor confirmed the successful functioning of the system.
This blue light is generated by ionized xenon accelerating from the motor. Although the generated force is extremely small, it is compared to the size of a sheet of paper placed on the palm of a hand. Nevertheless, this weak force is part of the solar electric propulsion system, which is intended to deliver the MBR Explorer spacecraft to a distance of approximately five billion kilometers through the Solar System.
Unlike chemical engines, which provide powerful but short bursts of thrust by consuming large amounts of fuel, electric propulsion allows for the efficient application of much smaller thrust over a long period. Al Hammadi, an electric propulsion engineer within the UAE Asteroid Belt Mission, notes that this characteristic makes the system suitable for such a large-scale journey.
NASA's Psyche mission uses a similar principle, accelerating xenon ions using electric and magnetic fields to create a constant, albeit small, force in deep space. According to NASA, the thrust of the Psyche system is comparable to the weight of an AA battery in the palm of a hand.
However, for the UAE mission, generating thrust is only the beginning of the tasks. This week, the UAE unveiled a separate lander probe that will be placed aboard the MBR Explorer and will eventually reach the object 269 Justitia. This probe has reached flight readiness and is scheduled to travel to Colorado for final integration with the main spacecraft before the planned launch in March 2028.
The MBR Explorer itself plans to use gravitational maneuvers around Venus, Earth, and Mars, encounter six asteroids, and ultimately reach Justitia in 2036. For engineers working on the spacecraft, another complex question arises: how to test a device today if it is meant to operate years later when no one can repair it?
When asked about the most difficult engineering problem of the mission, Al Hammadi did not name a specific component or engine. She replied that the most challenging aspect on a personal level is dealing with uncertainties, meaning the possibility of what might go wrong.
This includes questions about how much fuel will actually be consumed, whether the engine will provide the expected force, how temperatures inside the tanks might change, and how uncertainties in various spacecraft systems interact. Engineers account for all known information about the system and all participating subsystems, converting these uncertainties into acceptable limits that the spacecraft will bear.
Testing is conducted repeatedly and at different levels. The UAE's technical document on the solar electric propulsion program describes component testing, leak and pressure checks, thermal assessments, module-level testing, and additional checks after environmental qualification before the spacecraft is fueled for launch.
Space missions are designed with the understanding that equipment cannot simply be returned to the workshop. Al Hammadi emphasized: 'If you launch it, it won't come back.' Unlike hardware, software can sometimes be updated after launch. Therefore, wherever possible, systems are built with redundancy. Mission planners also study emergency response scenarios in advance.
Al Hammadi added that in case of a serious propulsion system issue, one option could be to forgo some planned asteroid encounters and adapt the mission to what remains operational. 'You cannot fix it, but you also have plans to meet the success criteria that suit you and what is already working on the spacecraft.'
Dr. Elias Tsoucanis, a senior researcher at the TII Center for Motion and Space Research, noted that the scale of EMA makes such preparation particularly demanding. He stated that the mission involves about 40 maneuvers compared to five maneuvers in the UAE Mars mission, covering nearly ten times the distance. 'We are talking about a five-billion-kilometer journey in deep space,' he said. 'It is both very exciting and very complex.'
The spacecraft must also withstand drastically different temperature conditions while maintaining the reliability of electronics and other systems throughout the flight. Tsoucanis stated: 'We cannot build a system and then think about autonomy after we have built it. Reliability, autonomous operation, and extensive testing are integral parts of the program from the very beginning.'
The engineering challenge also lies in the evolution of capabilities within the UAE. Al Hammadi noted that before the EMA mission, electric propulsion was not a capability of the UAE. She previously studied mechanical engineering before transitioning to space systems and electric propulsion, a field that required her to study unfamiliar areas, including electrical engineering and electromagnetism. 'I had no idea what electric propulsion was,' she said. 'I knew I wanted to bring it back.'
Since then, TII has developed specialized infrastructure in Abu Dhabi for working with electric propulsion. Al Hammadi reported that the center now has two large vacuum chambers and a smaller chamber for electronics and power processing systems, allowing engineers to test propulsion equipment under conditions that replicate some aspects of space.
A research paper from the UAE Space Agency describing this facility indicates that it was designed with three vacuum chambers, specialized diagnostics, thrust measurement, cleanrooms, and engineering workshops, creating infrastructure for the research, development, and testing of electric propulsion systems in the country.
Tsoucanis argues that the broader shift is not just about objects. Four years ago, he said, responsibility for developing a system like the UAE's lander probe would likely have fallen to someone else. 'It would probably have been outsourced, handed over to another partner, another colleague in another country,' he said. Instead, teams based in the UAE have progressed from providing personnel for a broader mission to taking responsibility for designing, assembling, and testing a complete deep-space probe.
'We were tasked with performing a real design and engineering task in the UAE,' Tsoucanis said. 'Now we have just completed our extensive testing. Environmental testing is truly difficult, and that is where it is really felt.'
The mission is part of a broader effort to turn space programs into an industrial opportunity. The UAE's National Space Strategy until 2031 aims to double revenues from the space economy, increase the sector's added value by 60 percent, and expand national companies, infrastructure, and exports.
TII is also developing propulsion systems beyond EMA. In February, the company launched the first hybrid rocket probe in the UAE, developed and tested domestically, which reached an altitude of about three kilometers.
For Al Hammadi, progress is easier to understand by comparing UAE interplanetary missions. 'When we started with the UAE Mars Mission about 10 years ago, the idea was that the UAE just wanted to be part of it. The next mission, EMA, which we are conducting now, is the UAE wanting to build it. And inshallah, the next one will be led by us.'
Tsoucanis sees the same transformation. Engineers involved in earlier missions are now taking on larger responsibilities, and the national team has grown in both size and technical depth. For him, reaching Justitia in 2036 will be a remarkable operational achievement. But, in his opinion, part of the mission's goal has already been achieved: 'The mission is already a success in the sense that we have developed talent in the country and national capability. Not just exploring space, but developing people.'
Al Hammadi views it more personally: 'We are essentially the first generation doing this.'
Before the MBR Explorer reaches the asteroid, it still has years of testing, launching, and deep space travel ahead. However, long before the MBR Explorer reaches the asteroid, some of the most lasting elements of the mission may be the knowledge, people, and objects it leaves behind on Earth.