The probe that travels towards the Sun directly observes one of its great mysteries

The Solar Orbiter probe, which travels towards the Sun, has solved one of the mysteries that intrigue scientists on our star, by making the first direct and consistent observation of a phenomenon called magnetic whiplash.

The recorded data provide “convincing clues” about the origin of this phenomenon and point to how its formation mechanism could help accelerate the solar wind, the continuous flow of energetic particles emitted by the solar corona, according to a study published in ‘The Astrophysical Journal Letters’.

A magnetic whip is large and sudden deviations of the magnetic field of the solar wind. Observations by the European Space Agency (ESA) probe have confirmed that this phenomenon is S-shaped, as predicted, and that may have its origin near the photosphere (outer layer of the Sun).

These lashes could be one of the mechanisms that help explain one of the great mysteries of the Sunthus answering the question of why the photosphere has much lower temperature than the crown (atmosphere), although it is early to draw conclusions, the astrophysicist at the University of Alcalá de Henares Javier Rodríguez-Pacheco tells Efe.

This phenomenon had already been detected by the Ulysses and Helios missionsbut with technology from the last century and only through data ‘in situ’, collected from the environment of the ships, and its explanation had been done theoretically.

Solar Orbiter is equipped with ‘in situ’ instruments and others that directly observe the Sun, which has made it possible to observe, for the first time, “live”, one of these lashesaccording to Rodríguez-Pacheco, principal investigator of the Energetic Particle Detector (EPD), one of Solar Orbiter’s instruments, although not involved in this study.

These mysterious inversions of the magnetic field, as observed by those first missions, “were always abrupt and temporary”, from a few seconds to several hours, before returning to their original direction, the ESA indicates in a statement.

The indirect detection of these whiplashes increased in 2018 with data provided by Nasa’s Parker Solar Probe, still in service.

The Solar Orbiter observations were last March with the Metis coronagraph, which takes pictures of the star’s outer atmosphereand recorded an image showing a distorted S-shaped fold in the coronal plasma, “suspiciously resembling a change in direction”, adds the ESA.

The data “support one of the theories about these whips or rare structures in the magnetic field, which associates its origin with the photosphere and near sunspots or active regions of the Sun,” says Rodríguez-Pacheco.

“I would say that this first image of a magnetic whiplash in the solar corona has revealed the mystery of its origin,” reveals Daniele Telloni, from the Astrophysical Observatory of Turin (Italy) and one of the study’s signatories.

The lashes would correspond to very slow moving plasma above an active region of the Sun it has yet to release its stored energy.

In October it will make its closest passage to the Sun

Solar Orbiter will perform on October 13 its closest step to the sunabout 42 million kilometers away, for which this week it flew over Venus, when it was hit by a large coronal mass ejection.

The probe was not damaged as it is prepared “For this type of harsh conditions,” says Rodríguez-Pacheco, who highlighted the great intensity of the ejection, with a speed of about 1,100 kilometers per second, and that it occurred only a few days after another even more powerful one, about 1,300 .

Waiting to receive and analyze all the data, the scientist points out that the second ejection produced more high-energy particles than expected, which could be due to the fact that it collected those already generated by the first one.