The extreme solar transient events as observed by the MAG payload onboard Aditya-L1 spacecraft around L1 point

Abstract

Aditya-L1 is the first Indian spacecraft placed in a halo-orbit around the first Lagrangian (L1) point to continuously observe the Sun. A fluxgate magnetometer (MAG) is also onboard with other payloads to measure the interplanetary magnetic field (IMF) coming from the Sun towards the Earth which is an important parameter in monitoring the near-Earth space weather. The MAG is a dual triaxial sensor set mounted on a 6 m long boom, deployed along the negative roll direction of Aditya-L1, with one set at the tip of boom and the other set at the centre of the boom around 3 m away from the spacecraft towards the boom-tip on the sun-viewing panel deck. The MAG boom was deployed (downwards from the spacecraft) on January 11, 2024 and since then MAG is measuring the IMF. MAG observations are found to match well with the magnetic field measurements of the Deep Space Climate Observatory (DSCOVR) from NOAA, USA. During its continuous operations since then MAG has observed several extreme solar transient events such as the Interplanetary Coronal Mass Ejections (ICMEs), Magnetic Clouds etc. In this paper we report MAG observations of passage of three ICMEs during September–October, 2024 which occurred due to extreme solar transient events. As the selected events led to severe geomagnetic storms Dst < − 100 nT, the impact of these events on the Earth’s magnetosphere are presented.