461717.fig.0016
Figure 16: Fluxes of solar protons observed on Prognoz-1. Within 70 days eight increases of SCRs were observed with exponential decay profiles (energy Ep 1 MeV) of nearly identical characteristic times τ = 16.5 hours. This provides an evidence of long-term (more than two solar rotations) stationary state of the interplanetary medium in the inner heliosphere.