Vibrations of the sun – Focus.it

The sun vibrates and rings and vibrates and vibrates. Some of these motions were known, and others were discovered as we increase our ability to study our star and interpret data from probes, telescopes and other instruments. The latest discovery was published in the Journal of Astronomy and Astrophysics (available In the full PDF version of this page), from a group of heliophysics led by Laurent Gizon, Del Max Planck Institute for Solar System Research (MPS): Researchers have detected vibrations of very long durations involving the Sun as a whole with periods It corresponds to the rotation of the Sun (27 days). These vibrations appear on the surface of our star as huge vortices moving at a speed of five kilometers per hour.

In the video above: Illustration of data and study model for massive waves of material traveling on the surface of the Sun; The sounds were obtained by shifting the frequency of the wave to the range audible to the human ear.

The discovery emerged from studying data obtained by the spacecraft Solar Dynamics Observatory (SDO) From NASA, collected over a period of about ten years, and with the help of complex simulations, scientists have also shown that these vibrations are due to differential rotation In fact, our star rotates at different speeds between the poles and the equator, because it is not a solid body like the Earth, which rotates uniformly around itself, but a gaseous body. According to the researchers, the study of these vibrations will help to study the structure and dynamics of the Sun.

like a bell. Other vibrations, as if the sounds of a vibrating bell, have been known since the 1960s: they are produced by streams of plasma (a gas at a very high temperature), near the surface, which produce real sound waves with intervals of about five minutes .. which are still trapped inside the Sun. With the help of ground and space telescopes, these rapid oscillations have been continuously monitored since the mid-1990s. Just as seismologists use earthquakes to explore the Earth’s interior thanks to those vibrations eliosismologi They have made important strides in understanding solar structure and dynamics. One of the great successes of helioscience has actually been the mapping of the sun’s rotation as a function of depth and latitude.

Certain predictions. For more than forty years, solar physicists have predicted that stars should also have oscillations with significantly longer periods, but so far they have not been identified on the Sun: a study by Gison and colleagues confirms these predictions. “Long-term vibrations depend on the rotation of the Sun, but to determine them it was necessary to measure horizontal motions on the surface of our star for many years – a task made possible by continuous observations usingSolar and magnetic imaging SDO. “

In the Sudio path, in addition to the long-term vibrations, a few dozen other vibrations were also detected, each with its own vibration period, and onde in RossbyIt was identified on the surface of the Sun in 2017 by another team of researchers (Study in nature). Kieran Jane (National Solar Observatory, USA) concludes that “computational models allowed us to ‘see’ the interior of the Sun and formulate consistent hypotheses about the structure of the three-dimensional vibrations”: “The discovery and study of a new type of solar vibration is of great interest, because it allows by drawing conclusions about the complex and unknown properties of our star, such as the power of a heat engine – which causes matter to rise from the depths of the sun towards the surface and which controls the great motions that occur within it.”