SREM measurements of Earth's radiation belts
These plots show the radiation measurements obtained with SREM on board Rosetta, as the spacecraft passed through the Earth's radiation belts during the mission's third Earth swingby. Closest approach occurred at 07:45:40 UTC on 13 November 2009, when Rosetta was at an altitude of 2481 km.
The top two panels show the distance of Rosetta from the Earth (in Earth radii [RE]), together with count rates for three of the SREM channels. The TC3 channel is sensitive to electrons (>500 keV) and protons (>10 MeV), TC1 for electrons (>2 MeV) and protons (>27 MeV), and S34 for protons only (>11 MeV).
The bottom two panels show the Earth's magnetic field strength and the derived electron fluxes in different energy ranges as a function of geomagnetic coordinates. The three plotted electron energy ranges are 0.5-1.0 MeV, 1.0-2.3 MeV and 2.3-5.0 MeV.