JEM-EUSO

The objective of the JEM-EUSO program, Joint Exploratory Missions for Extreme Universe Space Observatory, is the realization of a space mission devoted to scientific research of cosmic rays and neutrinos of highest energies by measuring ultraviolet fluorescence from extensive air showers and Cherenkov light reflected from ground or clouds. The program has advanced dedicated optics and electronics through a coordinated suite of validation experiments and international collaboration. For more information, visit the JEM-EUSO official website.

• Collaborators: Physicists and engineers from 8 member countries (Czech Rep., France, Germany, Italy, Japan, Poland, Russia, USA) plus 4 associated countries (Korea, Slovakia, Sweden, Switzerland).
• Pathfinder experiments: EUSO‑TA (ground), balloon campaigns EUSO‑Balloon, EUSO‑SPB1, EUSO‑SPB2, PBR, and orbital tests TUS and Mini‑EUSO (on the ISS since 2019).
• Science reach: Validates UV/Cherenkov techniques, enables Earth‑skimming neutrino searches, and detects transient UV phenomena (meteors, sprites/ELVES, bioluminescence, exotic signatures).
• Future: Results feed design and readiness for large missions such as K‑EUSO, POEMMA, and M‑EUSO to resolve UHECR origins.