Back on the 1st of December 2023, Ireland's first satellite called EIRSAT-1 was launched on a SpaceX Falcon-9 rocket from Vandenberg Space Force Base in California.
Now 22-months later in early September 2025, it's mission comes to a close as it is expected to burn up in the next few days in the earths atmosphere.
At the time of writing, it's altitude is about 220kms which is well within the ionosphere and where it will start to experience significant drag from air molecules.
During its mission, EIRSAT-1 carried three payloads / experiments. One was a Gamma-Ray Module (GMOD) to detect gamma ray bursts, one was the ENBIO module, a materials testing platform to test the performance of thermal management coatings in LEO for the first time and the final one was the the Wave Based Control (WBC) module, which tested and validated a novel control system for advanced satellite pointing in space.
The successful validation of its Wave-Based Control system was one of the more interesting ones. The software-led payload that lets satellites fine-tune their orientation mid-orbit. This was developed at University College Dublin (UCD) and the systm uses magnetorquers (tiny coils that push against Earth’s magnetic field) and a clever algorithm inspired by spinning tops.
Once the satellite starts spinning, the gyroscopic stability lets the controller nudge it in any direction. The result is that pointing accuracy within a few degrees is achieved. Dr. David McKeown of UCD called it a “major milestone.”
Some satellites wish to use the very high communication bandwidths available by using lasers as opposed to microwave links and precise pointing is critical for such space space missions.
