Computer-processed streamer chamber photograph of the tracks of subatomic particles produced in a proton- antiproton collision at a total energy of 900 GeV. The collision was recorded in the UA5 detector at CERN, the European particle physics laboratory outside Geneva. The proton & antiproton have come in from the sides of the picture & annihilated at centre into pure energy; this energy rematerialises in a spray of new particles, mostly pions. Recorded 1985