Related Experiment Video
Updated: Jul 9, 2026
06:14
Simulating Imaging of Large Scale Radio Arrays on the Lunar Surface
Published on: July 30, 2020
Are there Alfvén waves in the solar atmosphere?
1Solar Physics and Space Plasma Research Centre, Department of Applied Mathematics, University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH, UK. robertus@sheffield.ac.uk
Science (New York, N.Y.)
|December 8, 2007
Summary
The Sun's corona is millions of degrees hotter than its surface. Hinode spacecraft data reveal magnetic fields and plasma waves are key to coronal heating, advancing solar research.
Area of Science:
- Solar Physics
- Plasma Physics
- Astrophysics
Background:
- The Sun's corona reaches millions of Kelvin, significantly hotter than the visible solar surface.
- The energy sources and mechanisms maintaining coronal temperatures remain a significant puzzle in solar research.
Purpose of the Study:
- To investigate the energy transport mechanisms responsible for heating the Sun's corona.
- To analyze plasma properties in the Sun's outer layers using advanced observational data.
Main Methods:
- Utilizing data from the Hinode spacecraft for high-resolution observation of the Sun's outer layers.
- Measuring plasma properties and analyzing magnetic field interactions.
Main Results:
- Hinode data highlight the crucial role of magnetic field interactions in coronal heating.
- Evidence suggests that plasma waves play a significant role in transporting energy to the corona.
Conclusions:
- Magnetic fields and plasma waves are identified as primary drivers of coronal heating.
- The Hinode mission has ushered in a new era of detailed solar observation, enhancing our understanding of coronal plasma dynamics.
Related Concept Videos
01:11Atomic Nuclei: Larmor Precession Frequency
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession, and the angular frequency...
01:30Electromagnetic Waves
James Clerk Maxwell formulated a single theory combining all the electric and magnetic effects scientists knew during that time, calling the phenomena his theory predicted “Electromagnetic waves”. He brought together all the work that had been done by brilliant physicists such as Oersted, Coulomb, Gauss, and Faraday and added his own insights to develop the overarching theory of electromagnetism. Maxwell’s equations, combined with the Lorentz force law, encompass all the laws of electricity and...
01:30Electromagnetic Waves in Matter
Electromagnetic waves can travel in the vacuum as well as in matter. For example light, which is an electromagnetic wave, can travel through air, water, or glass.
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the medium, μ.
Furthermore, the...
Consider the electromagnetic wave passing through a dielectric medium. In such a case, Maxwell's equations get modified. In Ampere's law, ε0 , the dielectric permittivity of free space is replaced with ε, the permittivity of dielectric. Also, the vacuum permeability μ0 is replaced by the permeability of the medium, μ.
Furthermore, the...
01:22Energy Carried By Electromagnetic Waves
Anyone who has used a microwave oven knows there is energy in electromagnetic waves. Sometimes, this energy is obvious, such as in the summer sun's warmth. At other times, it is subtle, such as the unfelt energy of gamma rays, which can destroy living cells. Electromagnetic waves bring energy into a system through their electric and magnetic fields. These fields can exert forces and move charges in the system and, thus, do work on them. However, there is energy in an electromagnetic wave,...
01:24Electromagnetic Wave Equation
Maxwell's equations for electromagnetic fields are related to source charges, either static or moving. These fields act on a test charge, whose trajectory can thus be determined using suitable boundary conditions. The objective of electromagnetism is thus theoretically complete.
However, although electric and magnetic fields were first introduced as mathematical constructs to simplify the description of mutual forces between charges, a natural question emerges from Maxwell's equations: What...
However, although electric and magnetic fields were first introduced as mathematical constructs to simplify the description of mutual forces between charges, a natural question emerges from Maxwell's equations: What...
01:01Sound Waves
Sound waves can be thought of as fluctuations in the pressure of a medium through which they propagate. Since the pressure also makes the medium's particles vibrate along its direction of motion, the waves can be modeled as the displacement of the medium's particles from their mean position.
Sound waves are longitudinal in most fluids because fluids cannot sustain any lateral pressure. In solids, however, shear forces help in propagating the disturbance in the lateral direction as well. Hence,...
Sound waves are longitudinal in most fluids because fluids cannot sustain any lateral pressure. In solids, however, shear forces help in propagating the disturbance in the lateral direction as well. Hence,...