Comparison of Vlasiator proton precipitation and DMSP/SSJ observations on 1 August 2011. (a–b) Integrated energy flux shown in polar MLT–MLAT coordinates for Vlasiator and DMSP F18 (northern hemisphere, panel a) and DMSP F16 (southern hemisphere, panel b). The Vlasiator data correspond to time averages between t = 900 and t = 1506 s. (c–d) The same data along the satellite orbits, shown as time series. The orange line corresponds to the DMSP/SSJ fluxes, the solid green line gives the time-averaged Vlasiator flux, the green shaded area indicates the ±1σ (standard deviation) interval, and the dotted green line shows the maximum flux value during the considered simulation time range. (e–f) Differential number flux of precipitating protons along the satellite orbits in Vlasiator (background colours, time-averaged) and DMSP/SSJ observations (isocontours).