Aditya-L1, India's first space-based solar mission, watches the Sun from a halo orbit around the Sun-Earth L1 point

Background

Aditya-L1 is the first space-based Indian mission to study the Sun. The spacecraft is placed in a halo orbit around Lagrange point 1 (L1) of the Sun-Earth system, which is about 1.5 million km from the Earth. A satellite in a halo orbit around L1 can view the Sun continuously without any occultation or eclipse, which allows solar activity and its effect on space weather to be observed in real time. The spacecraft carries seven payloads to observe the photosphere, the chromosphere and the corona using electromagnetic, particle and magnetic field detectors. Four payloads view the Sun directly: the Visible Emission Line Coronagraph (VELC) for coronal imaging and spectroscopy, the Solar Ultraviolet Imaging Telescope (SUIT) for photospheric and chromospheric imaging, the Solar Low Energy X-ray Spectrometer (SoLEXS) and the High Energy L1 Orbiting X-ray Spectrometer (HEL1OS). Three payloads carry out in-situ studies of particles and fields at L1: the Aditya Solar wind Particle Experiment (ASPEX), the Plasma Analyser Package for Aditya (PAPA) and advanced tri-axial high resolution digital magnetometers. The science objectives include the problem of coronal heating, the physics of partially ionised plasma, the initiation of coronal mass ejections and flares, the diagnostics of coronal plasma temperature, velocity and density, magnetic field measurements in the solar corona and the drivers of space weather. ISRO launched the observatory on PSLV-C57 and the spacecraft was inserted into its halo orbit around L1 on 6 January 2024.