Lecture

Plasma Astrophysics: Solar Dynamics

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Description

This lecture explores how fusion energy powers the Sun, a nuclear reactor that confines plasma through gravitational pull. It delves into the solar magnetic field's structure, revealing a process converting plasma flow energy into magnetic energy. The interaction of magnetic fields via reconnection leads to plasma heating and particle acceleration, driving powerful solar events like coronal mass ejections. The solar wind shapes Earth's magnetosphere, and these topics are discussed using plasma physics basics. Dr. Ivo Furno, head of the Basic Plasma Physics and Applications Group at CRPP, will present the lecture.

In MOOC

Plasma Physics: Applications

This physics course, taught by world-renowned experts in the field, will provide you with an overview of applications in plasma physics. From the study of far distant astrophysical objects, over diverse applications in industry and medicine, to the ultimate goal of sustainable electricity generation from nuclear fusion. In the first part of this course, you will learn how nuclear fusion powers our Sun and the stars in the Universe. You will explore the cyclic variation of the Sun’s activity, how plasma flo

Official source

Ontological neighbourhood

Physics

Plasma physics: Space-plasma physics

Related concepts (29)

Solar phenomena

Solar phenomena are natural phenomena which occur within the atmosphere of the Sun. These phenomena take many forms, including solar wind, radio wave flux, solar flares, coronal mass ejections, coronal heating and sunspots. These phenomena are believed to be generated by a helical dynamo, located near the center of the Sun's mass, which generates strong magnetic fields, as well as a chaotic dynamo, located near the surface, which generates smaller magnetic field fluctuations.

Coronal mass ejection

A coronal mass ejection (CME) is a significant ejection of magnetic field and accompanying plasma mass from the Sun's corona into the heliosphere. CMEs are often associated with solar flares and other forms of solar activity, but a broadly accepted theoretical understanding of these relationships has not been established. If a CME enters interplanetary space, it is referred to as an interplanetary coronal mass ejection (ICME).

Solar wind

The solar wind is a stream of charged particles released from the upper atmosphere of the Sun, called the corona. This plasma mostly consists of electrons, protons and alpha particles with kinetic energy between 0.5keV. The composition of the solar wind plasma also includes a mixture of materials found in the solar plasma: trace amounts of heavy ions and atomic nuclei of elements such as C, N, O, Ne, Mg, Si, S, and Fe. There are also rarer traces of some other nuclei and isotopes such as P, Ti, Cr, 54Fe and 56Fe, and 58Ni, 60Ni, and 62Ni.

Fusion power

Fusion power is a proposed form of power generation that would generate electricity by using heat from nuclear fusion reactions. In a fusion process, two lighter atomic nuclei combine to form a heavier nucleus, while releasing energy. Devices designed to harness this energy are known as fusion reactors. Research into fusion reactors began in the 1940s, but as of 2023, no device has reached net power. Fusion processes require fuel and a confined environment with sufficient temperature, pressure, and confinement time to create a plasma in which fusion can occur.

Coronal hole

A coronal hole is a temporary region of relatively cool, less dense plasma in the solar corona where the Sun's magnetic field extends into interplanetary space as an open field. Compared to the corona's usual closed magnetic field that arches between regions of opposite magnetic polarity, the open magnetic field of a coronal hole allows solar wind to escape into space at a much quicker rate. This results in decreased temperature and density of the plasma at the site of a coronal hole, as well as an increased speed in the average solar wind measured in interplanetary space.

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