Aditya-L1 mission of India and potential of in-situ measurements

The Aditya-L1 mission is India's first dedicated observatory class mission to investigate the Sun and the heliosphere uninterruptedly from the first Lagrangian point (L1) of the Sun-Earth system. There are seven experiments on-board Aditya-L1. Four of these experiments will probe the Sun in remote sensing mode whereas three in-situ experiments will measure particles and magnetic fields. The remote sensing experiments are Visible Emission Line Coronagraph (VELC), Solar Ultraviolet Imaging Telescope (SUIT), Solar Low Energy X-ray Spectrometer (SoLEXS) and High Energy L1 Orbiting X-ray Spectrometer (HEL1OS). These experiments are designed to address the dynamical events in the solar atmosphere that includes photosphere, Chromosphere and Corona in addition to the spectroscopic investigation of the coronal plasma. The in-situ experiments include the Aditya Solar Wind Particle Experiment (ASPEX), Plasma Analyzer Package for Aditya (PAPA) and Magnetometer (MAG). Through these experiments, the solar wind (ions and electrons), supra-thermal and solar energetic particles as well as magnetic field will be measured in multiple directions from the first Lagrangian point (L1) of the Sun-Earth system. Such measurements can throw light on a number of complex processes (like origin, acceleration, seed population, anisotropy etc.) that are not comprehensively understood till date. Understanding on such processes are of paramount importance to gauge the impact of solar processes on the planetary upper atmospheres, ionospheres and magnetospheres. The talk will highlight the potential of these in-situ measurements in solving exciting and unresolved scientific issues related to the Sun, heliosphere and planetary atmosphere.