Assertion: cosmic ray's energy | /r/CapableOf | start cascade
Facets:
value: at the top of the atmosphere
type: LOCATION
Source sentences:
text: Thus the observations seemed best described by the theory of multiplicative electron-photon cascades, with an electron (or positron or photon) of very high energy starting a cascade at the top of the atmosphere, which then built up to a maximum number of particles part way down, and would be dying away in the lower atmosphere.