Science Objectives

The Universe is permeated by hot, turbulent magnetized plasmas. They are found in active galactic nuclei, supernova remnants, the intergalactic and interstellar medium, the solar corona, the solar wind, and the Earth's magnetosphere, just to mention a few. Our knowledge and understanding of the Universe is largely based on measurements of electromagnetic radiation such as light or X-rays, which originate, in most cases, in hot plasmas. It is thought that energy dissipation of turbulent fluctuations in plasmas plays a key role in plasma heating and energization. It is remarkable that we still do not understand the underlying physical mechanisms! Understanding these mechanisms is the unique mission of THOR. THOR will address the fundamental science theme Turbulent Energy Dissipation and Particle Energisation, which addresses ESA's Cosmic Vision theme "How does the solar system work?". In particular, THOR will address the following science questions:
  1. How are plasmas heated and particles accelerated?
  2. How is the dissipated energy partitioned?
  3. How does dissipation operate in different regimes of turbulence?
Turbulence at bow shock
Turbulence formation at the Earth's bow shock [Vlasiator simulation].

Density fluctuations in plasma turbulence [HVM 3D3V simulation].