by IPPOG Communication
International Cosmic Day 2026
International Cosmic Day 2026: explore the Universe through cosmic rays
On 19 November 2026, students and teachers from around the world will come together for the International Cosmic Day (ICD), a global event dedicated to exploring cosmic rays and the particles that reach us from space. Organised as an international science education activity, the International Cosmic Day gives students the opportunity to investigate cosmic rays through measurements and data analysis, while connecting with other participants and researchers from around the world.
Cosmic rays constantly reach Earth from space. When they interact with the atmosphere, they produce showers of secondary particles, including muons that can reach the Earth’s surface. These particles provide a way to explore phenomena originating far beyond our planet using detectors and measurements performed here on Earth. During the International Cosmic Day, students can experience this process themselves. Working with cosmic-ray measurements, they investigate particle behaviour, analyse their observations and discuss their results. The activity offers an opportunity to experience aspects of scientific research first-hand, from collecting and analysing data to interpreting results and communicating findings.
For students, ICD is also an opportunity to discover a different side of particle and astroparticle physics. Rather than only learning about particles and cosmic rays in the classroom, they can investigate them through practical activities and measurements. The event can help make abstract concepts more tangible while encouraging students to ask questions, analyse evidence and think like scientists.
The International Cosmic Day is also an opportunity for teachers to engage their students with contemporary particle physics and cosmic-ray research through an international outreach activity.
The next International Cosmic Day will take place on 19 November 2026.
Teachers and groups interested in taking part should register by 25 October 2026.
More information about the programme, participation and registration is available on the International Cosmic Day website:
