Giant atmospheric showers detected by the Yakutsk extensive air showers array

The two most powerful extensive air showers (EAS) with energies of about 10 eV, registered at the Yakutsk EAS array during the entire observation period of 1974–2024, are considered. Both showers hit the array near the center and triggered all surface detectors and underground muon detectors with a threshold energy of = 1.0 · cos θ GeV. These events have an abnormally high fraction of muons, which is beyond current model predictions. This may change our understanding of hadron interactions at ultra-high energy, but there is also a possibility that these showers were initiated by some exotic primary particles.