Earth Magnetosphere, Solar Wind Interaction with Planetary Magnetospheres & Ionospheres - Theory, Observations & Simulations (EPTOS)

Chief Co-ordinator - Prof. Satyavir Singh & Members

Plasmas exist everywhere in the universe; in the interiors of stars, in stellar winds, in the highly energetic phenomena of stellar and galactic jets, and in the magnetospheres and ionospheres expected to surround extra solar planets. It is only in the solar system, however, that the fundamental physical processes that occur in plasmas can be studied directly and in detail, through in-situ measurements from spacecraft and sustained, high-resolution imaging from both space-based and ground-based observatories. The solar system thus serves as a “laboratory” for the investigation of processes common to all astrophysical plasmas.
The presence of charged particles (a plasma) together with electric and magnetic fields makes space a very fascinating and challenging world to explore. The interaction between the Earth´s magnetic field and the solar wind (a stream of charged particles dragging the Sun's magnetic field with it) creates a cavity surrounding the Earth known as the “magnetosphere”, which at least partially shields the Earth from the solar wind. The magnetic activity in the Sun creates disturbances to the solar wind, which drive versatile and complex processes and phenomena in the geospace. In the geospace, the solar wind, magnetosphere, and ionosphere form a single system driven by the transfer of energy and momentum from the solar wind to the magnetosphere and ionosphere. The plasma dynamics in this coupled system is quite complex in nature as the plasma behavior is characterized by multiple interactions or “couplings” between different plasma regions and energy regimes, between different populations of particles, between different processes, and across different spatial and temporal scales. Therefore, it is necessary to understand how small-scale processes control large-scale phenomena, for example, magnetosphere-solar wind coupling processes, plasma entry through the magnetopause and cusp, magnetotail dynamics, magnetosphere-ionosphere coupling, field-aligned electric fields, plasma waves and instabilities, and turbulence in the Sun-Earth plasma system.
This scientific group at IIG has a strong research program aimed at understanding how energy carried by the solar wind is transferred into the magnetosphere dispersed through the system and eventually deposited in the atmosphere. This includes plasma processes that involve energization, transport, and loss of charge particles in the Earth’s magnetosphere. This program utilizes satellite and ground-based data, together with theoretical analysis and computer simulation modeling, and involves extensive collaboration with the national and international space science community.
While it is particularly important to understand the plasma processes in Earth’s ionosphere and magnetosphere, the knowledge gained here can be transferred to fundamentally similar systems both at the other magnetized bodies in the solar system and indeed throughout the universe.In this context, the team of EPTOS program has recently planned to investigate the solar wind interaction with the other planetary ionospheres and magnetospheres in the heliosphere.