Dust grain origin of cosmic ray air showers

It is suggested that cosmic rays of energies as high as 10²⁰ eV consist of dust grains of relativistic energies. Such dust grains as typical in interstellar space are accelerated first by a strong radiation pressure of luminous, compact galaxies and then by magnetic processes. A grain with the mass of about 10^–16 g and the Lorentz factor of about 10³ attains an energy as large as 10²⁰ eV and produces a huge extensive air shower. Such grains survive against the collisions with cosmic microwave photons. This would remove the serious difficulty, if both the cosmic microwave radiation and the huge extensive air showers, which were regarded as due to protons of energies greater than 10¹⁹ eV, existed in spite of that the protons should strongly attenuate by the collisions with the radiation.