On this day, the focus is on the science related to cosmic rays. These are invisible messengers from the cosmos that constantly permeate us, bringing messages that allow us to understand the Universe. Let's learn more about these unknown particles from the cosmos and talk about them together.

Every participating group will plan its own event. Events could include activities such as discussions on cosmic particles, news about the latest research, or even the direct measurement and/or data analysis of cosmic particles.

Formats that can be used are: Lectures, Masterclasses or Masterclasses@home, video transmissions to the classroom, tasks that the students can do in school or at home. On this page we will collect ideas for activities that can be offered. We will also announce events that can be joined by people nationwide, e.g. lectures via livestream. You are welcome to suggest activities to us. There are no limits to your ideas. The most important thing is that we all stay healthy.

At the conclusion of the day, it would be great if you could summarize your findings on cosmic rays and what you did during the day in a PDF file. We will add your contribution to a booklet (see Proceedings) and make it available to all participants.



  • Welcome Call
    As we do every year, there was a Welcome from the headquarters. We are pleased to welcome guests to the Welcome Call again this year. You can watch the recorded Welcome Call here:


  • Video Calls
    We organize video calls for the groups to share their results and new insights. In the video calls, the students can present their results to each other, ask each other questions and discuss new findings. More information can be found in the organizers' section. 


  • Online Introductions
    We are pleased to offer online lectures on the topic of cosmic rays for the first time. In this videos we explain...



  • Data Analysis by OCRA 
    The INFN OCRA collaboration provides a series of online activities for cosmic ray data analysis on its webpage (only available in Italian) After an introduction on various techniques for the detection of cosmic rays with experiments on the Earth, a laboratory section offers the possibility to analyse the data of real experiments, from educational activities like a cosmic ray telescope located in a Naples metro station to data from experiments dedicated to frontier research, like the Auger observatory in the Argentinian pampa. 



  • Data Analysis by EEE Project

    For this edition of the ICD, the EEE Project has prepared an online meeting during which, together with presentations by researchers engaged in the study of cosmic rays, students will be able to present the results of the analyses.  In particular, we propose to students to study the variation of the cosmic ray flux as a function of the direction of arrival:


  • Data analysis with KCDC

    KCDC (KASCADE Cosmic Ray Data Centre) is a public data centre for high-energy astroparticle physics based on the data of the KASCADE experiment. KCDC offers a wide range of resources, including the outreach ones. The tutorials and examples at KCDC’s website represent a compilation of interesting lessons within the vast field of cosmic radiation to illustrate the processes within and outside of our atmosphere by means of the data sets of the KASCADE experiment. On the KCDC's JupyterLab one can find some tutorials, based on KASCADE, TRVO and and IceCube data samples. For more details, see the Instruction_analysis_with_KCDC.pdf (PDF, 43KB).


  • Do you like painting or photography? Then take part in the Drawing or Selfie Contest: 

    Drawing Contest
    Draw your favorite cosmic particle. Post it on Facebook or Instagram and use the hashtag #InternationalCosmicDay. The contest is open until Sunday November 14, 2021. The best one will get a prize!
    Here is an example from our scientist Nora Feigl working on IceCube:


        And an example from our scientist Heike Prokoph working on CTA and H.E.S.S.:

  • Selfie Contest

    Take a selfie of you with your detector or your favorite Cosmic Ray plot. Post it on Facebook or Instagram and use the hashtag #InternationalCosmicDay. The contest is open until Sunday November 14, 2021. The best one will get a prize!
    For inspiration, the photo that won in 2019: a group from INFN Gran Sasso:


  • Quiz

    Once again this year we have prepared a quiz for you on Kahoot. The quiz is open until Sunday November 14, 2021.Let's see who will be the world's best expert on cosmic rays! The access code is: 02204084