Data plots from the PEACE experiment
Spacecraft 1 and 2 show rather pronounced reductions in measured electron counts (less green and yellow, more blues) during the penumbra crossing, as one might expect from their longer crossing through the penumbral shadow. White horizontal bars indicate the duration of the penumbral passage, as predicted by the European Space Operations Centre in Germany. The vertical red bar indicates the estimated region of lowest photoelectron fluxes (using the yellow band around 5 eV).
Data courtesy of PEACE Principal Investigator, Dr. Andrew Fazakerley (Mullard Space Science Laboratory, UCL)