Record energy of a giant shower

According to a reliable (chi(1)(2)=0.93 with 36 degrees of freedom) interpr etation of the readings of all triggered detector stations in a giant showe r, detected at the Yakutsk array on May 7, 1989 at 13 h 23 min Greenwich ti me, in terms of the quark-gluon strings model with the geomagnetic field ta ken into account, the energy of this shower was 3x10(20) eV. (C) 1999 Ameri can Institute of Physics. [S0021-3640(99)00209-1].