The latest calculations of the magnetic field of the Sun have resulted in the first observational evidence that massive tornadoes in the star‘s atmosphere are triggered by spinning magnetic fields. The information was found and then shared by an international team of scientists.
The continual rotational motions of the Sun’s surface produces enormous tornadoes in the chromosphere, an atmospheric layer of the star. The tornadoes have a diameter of about a few thousand kilometers and carry mass and energy high up into the atmosphere. Hence, they are analyzed as energy channels to explain the incredible heating of the solar corona.
The main basic elements of solar tornadoes are intertwined magnetic fields. Still, it is incredibly challenging to measure the magnetic field in the Sun’s chromosphere, but this research has managed to offer the first direct observation of the chromosphere magnetic field to unveil the magnetic type of solar tornadoes.
In a study to be published in the Astronomy & Astrophysics journal, a team of scientists from the Italian National Institute for Astrophysics (INAF), the University of Warwick and the Italian Space Agency (ASI) has come with the first three-dimensional tomography of the magnetic fields coiling into a solar tornado and have measured their dim polarimetric signals.
This discovery was made possible because of incredible measurements taken with the INAF IBIS tool (Interferometric Bidimensional Spectrometer) at the DST solar telescope in New Mexico, the U.S.
Dr. Juie Shetye from the Centre for Fusion, Space and Astrophysics at the University of Warwick explains: “Direct measurements of the magnetic field in the chromosphere of the Sun has so far been elusive and this study is opening the door to a new era of solar research. Additionally, solar research is heading into a new epoch of solar observations with the opening of next-generation telescopes such as the 4-meter Daniel K. Inouye Solar Telescope in Hawaii, in which the U.K. and the University of Warwick is participating. This telescope will allow solar physicists to resolve magnetic fields at a local county level. We are at the start of an exciting journey that will unravel the new magnetic entanglements of the Sun.”
Swirling Magnetic Fields
The University of Warwick’s Dr. Erwin Verwichte’s complex analytical methods were utilized to analyze the fundamental nature of these waves.
Dr. Verwichte says: “These chromospheric tornadoes are natural laboratories for studying the propagation of waves and the energy they carry into the corona. Our study reveals that phase patterns of sound waves in the tornado can mimic rotation and need to be accounted for when measuring the strength of solar tornadoes.”
“The study of the transport and dissipation of energy in the Sun’s atmosphere is of fundamental importance for understanding the heating mechanisms of the outer regions of the Sun and the acceleration of the solar wind,” said Marco Stangalini (ASI) of the research team. “The magnetic fields swirling in these vortices represent the ideal physical conditions for the excitation of magnetic waves, which are considered to be one of the main players in the heating of the solar corona and in accelerating the solar wind. It is the first time that thanks to high-resolution spectropolarimetric IBIS data, it was achieved the three-dimensional tomography of the magnetic fields in these structures.”
The measurements performed with IBIS throughout the last few years have enhanced our knowledge of the solar atmosphere, but mainly of the structure and nature of the chromosphere, of the development of magnetic elements, and of the excitation and propagation of waves in magnetic regions.
Now, a team of experts is working to further improve the instrument, in order to operate it soon to collect new data of the Sun’s atmosphere with the resolution needed to enhance our understanding of physical processes fundamental to the solar activity and space weather.