Ireland's first cubesat EIRSAT-1 comes to end of life...

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 on the 4th of September 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.

Update - Thurs 4th Sept 2025...

...

16:00 UTC... It seems that the last reception of EIRSAT-1 was by VE9EX as the satellite passed over Newfoundland at 15:20 UTC.

There were no reports as it passed over South America, back up over Indonesia and South-East Asia and back down again over Canada and the United States.

It may well have re-entered and burnt up on this orbit, roughly about 16:00 UTC.

Last few reception reports

14:09 UTC - Heard over Brazil...

12:24 UTC - Heard in the Netherlands by PA0SAT...

12:21 UTC - Final pass over Ireland...

Slán go fóill

11:30 UTC - From the control team at UCD Dublin...

Still receiving EIRSAT-1 loud and clear over UCD Dublin this morning at approx 160km altitude.  Thanks to the radio amateur community @SatNOGS @LibreSpace_Fnd for tracking and sharing reports in these final hours of the mission.

Thanks to Department of Enterprise and Enterprise Ireland for your  support. Minister Alan Dillon TD: “I am very proud that the mission was supported by my Department,  through our membership of ESA (European Space Agency). EIRSAT-1 demonstrates the value of membership of  ESA for a  small country, such as Ireland"

11:00 UTC - Change in height (2nd Sep ~230kms, 3rd Sep 220kms, 4th Sep 190kms). Latest projection is that EIRSAT-1 will burn up sometime between 11:09 to 19:09 UTC.

09:29 UTC - Heard over Belarus. Note the doppler shift on the signal as it slopes to the left.

08:00 UTC - The latest orbit tracking shows an altitude of about 185kms which is about 30kms lower than yesterday.

VU2JEK in India decoded this message around 06:30UTC

The term 'Slán go fóill' is a traditional Irish parting message which means 'Bye for now'.

***

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 lets satellites fine-tune their orientation mid-orbit. This was developed at University College Dublin (UCD) and the system 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.

In conclusion... So ends the mission of EIRSAT-1. In international terms, it may seem like a minor project but the major accomplishment here was that a team at University College Dublin started from scratch and designed, built and operated a satellite.

They conducted some scientific experiments and showed that they could complete such a complex project.

It now allows the University to approach the European Space Agency for more projects in the future.