[en] PNST (Programme National Soleil-Terre/Sun-Earth National Program) is dedicated to analysis of the Sun-Earth system, from generation of the solar magnetic field, flares and coronal mass ejections, until impact on the terrestrial magnetosphere, ionosphere and thermosphere. Research activities carried out in the frame of Programme National Soleil-Terre (PNST) rely on both ground-based and space-borne instruments. One of the main objectives of PNST is to stimulate coordinated studies and to optimize scientific return of these instruments. The 2009 PNST prospective colloquium comprised 9 sessions: 1 - Eruptive activity in plasmas; 2 - Particles heating and acceleration; 3 - Energy transfers at different scales and turbulence; 4 - Coupling between the different envelopes; 5 - Sun-Earth relations and space meteorology; 6 - Sun and star prototypes; 7 - Databases, services; 8 - Instrumentation; 9 - Prospective. This document is the book of abstracts of the colloquium