EIRSAT-1. EIRSAT-1 (Educational Irish Research Satellite-1) is a European Space Agency-sponsored 2U CubeSat developed and built by University College Dublin (UCD) in Dublin, Ireland.

On 1 December 2023, EIRSAT-1 launched on a Falcon 9 rocket from Vandenberg Space Force Base, California. Upon reaching orbit, it became Ireland's first satellite.

Background 
In March 2017, UCD students and professors proposed the satellite to the European Space Agency (ESA) Fly Your Satellite! 2 (FYS 2) educational program for universities. In May 2017, UCD was one of six university teams selected to participate in the ESA FYS2 program. The mission passed its Preliminary Design Review (PDR) with both institutions involved, and following the Critical Design Review (CDR) in 2018, the mission has been developed and implemented by UCD with the support of the ESA Education Office. Lorraine Hanlon, EIRSAT-1 Endorsing Professor, introduced the project during a panel after the Irish premiere of the film "16 Levers de Soleil" on 31 January 2019.

The satellite cost €1,500,000 and is funded jointly by the ESA, the Irish Research Council, and Science Foundation Ireland.

Mission 
The mission of EIRSAT-1 is to advance education in space science and engineering across the whole island of Ireland through collaboration between student teams, higher education institutions and high-tech companies.

The objectives of EIRSAT-1 are to:
 develop the know-how of the Irish higher education sector in space science and engineering, by supporting student teams to build, test and operate the satellite;
 address skills shortages in the space sector by fostering collaboration between student teams and industry through the launch of three payloads that will demonstrate innovative Irish technology;
 inspire the next generation of students towards the study of STEM subjects by launching the very first Irish satellite.

Payloads 
EIRSAT-1 will carry three Irish developed experiments, or payloads.

GMOD - The Gamma-ray Module 
The first payload element (called the ‘Gamma-ray Module’ or ‘GMOD’) is a miniaturised sensor for use in the detection of gamma-rays from both cosmic and atmospheric phenomena. The sensor is called a silicon photomultiplier (SiPM) and has been developed by SensL Ltd. in County Cork (currently part of ON Semiconductor). The SiPM has the potential to revolutionise in-situ and remote sensing of gamma-rays in space by removing the need for conventional photomultiplier tubes that are typically very bulky, fragile and require high voltages to operate.

EMOD - the ENBIO Module 
The second payload element (called the ‘ENBIO Module’ or ‘EMOD’) will provide in-orbit demonstration of novel protective oxide surface treatments made by ENBIO Ltd. (SolarWhite and SolarBlack). These surface treatments have been developed for use on the ESA Solar Orbiter mission, and EIRSAT-1 will provide the opportunity for these coatings to be thermally tested. The temperature of the coatings will be measured throughout the mission.

WBC - Wave Based Control 
The third payload is a novel, software-based attitude control system developed by the Dynamics and Control Group in the UCD School of Mechanical and Materials Engineering. A spacecraft's “attitude” is its orientation in space. In this case it will use the Earth's magnetic field to turn itself in any desired direction. The UCD control technique is called “Wave-Based Control” (WBC). EIRSAT-1 will use a standard control system initially. At some time into the mission, in response to an instruction from Earth, the on-board computer will start using WBC to control the satellite's attitude, thereby evaluating its performance and, it is hoped, qualifying WBC for space flight.

Launch and operations 
Subject to successful reviews, the spacecraft was initially scheduled to be launched in 2023 on a Vega-C rocket as part of the Small Satellites Mission Service #5 rideshare mission. However after various delays the CubeSat was remanifested on the maiden flight of the Ariane 6 rocket. This was later changed to a rideshare payload of the South Korean 425 Project SAR satellite launch, which took place at 18:19 UTC on 1 December 2023 on a SpaceX's Falcon 9 Block 5 launch vehicle. The payload was launched into a Sun-synchronous orbit.

On 21 August 2024, the Gamma-ray Module onboard EIRSAT-1 detected its first gamma-ray burst (GRB), a long type GRB which was given the official designation GRB240821B. This type of GRBs is caused by the death of a high-mass star. Gamma-ray Module's second detection of a GRB was made just an hour and 19 minutes after the first one and it was a short one, a much rarer type which is likely caused by the collision of two neutron stars and the formation of a black hole. This second detection was given the official designation GRB240821A.

References 

Satellites of Ireland
Science and technology in Ireland
University College Dublin
Spacecraft launched in 2023
2023 in Ireland