One of the five spacecraft in the A-Train, launched in December 2004 by the Centre National d’Études Spatiales (CNES) of France to measure aerosols on what was planned as a two-year mission. It flew within about 30 seconds of the CALIPSO and CloudSat spacecraft until 2 December 2009, when CNES began to manoeuvre it out of the A-Train; it left the A-Train altogether at the end of 2012. Its place was to have been taken by Glory, but that mission failed at launch and was lost. The satellite was shut down on 18 December 2013.
https://parasol.cnes.fr/en/PARASOL/GP_mission.htm Mission.