The Sun has been by far the most studied star since the dawn of astronomy, particularly because of the essential role it plays in maintaining life on Earth. But paradoxically, this star remains rather poorly understood in certain key areas. For example, we have never had the opportunity to observe its poles: all the images you have seen of it have always been taken at the equator. Or at least, that was the case until very recently; for the first time, the ESA managed to capture images of one of the star's poles.
Today, the study of the Sun is mainly entrusted to two vehicles: the Parker space probe and the Solar Orbiter, operated by NASA and the ESA respectively. These are two complementary probes with different capabilities, but they share one thing in common: for both logistical and scientific reasons, they are orbiting close to the solar equator.
The NASA spacecraft is intended to remain in this orbit until the end of its mission. But this is not the case for its European counterpart. Since 2020, it has carried out five gravity assist maneuvers near the planet Venus. The objective: to gradually modify its orbit while expending a minimum of fuel. At the end of its last contact with the Evening Star, in February 2025, it had accumulated a 17° inclination relative to the solar equator — enough to allow it to observe its south pole for the first time.
Unprecedented images full of valuable data
The probe obviously took advantage of this opportunity to warm up its instruments. During its passage, it captured numerous images across a wide range of wavelengths, from visible to ultraviolet, which have just been published by ESA in its latest press release.
"Today, we reveal the first observations of the solar pole ever made by humanity," said Carole Mundell, the agency's chief scientist, in a press release. "These unique new images obtained thanks to our Solar Orbiter mission mark the beginning of a new era for solar science."
If this new angle is already making astrophysicists excited, it's because the Sun's poles are particularly interesting from a scientific point of view. They are the keystones of the heliospheric magnetic field, a phenomenon that is absolutely critical for both theoretical and practical reasons. It is this magnetic field that directly governs much of the star's activity, from sunspots to coronal mass ejections—those vast bubbles of plasma that can wreak havoc on our planet (see our article below).
An X-class solar flare caused a radio blackout on Earth
Understanding the dynamics of the sun's magnetic field therefore means understanding how the star works and how it influences its direct environment. And observations of the poles are perfect opportunities to make great progress in this field.
Perfect timing
The timing is ideal, and for good reason: we are currently in the midst of solar maximum, the peak of the star's 11-year activity cycle. It's an extremely dynamic period. Sunspots and flares, as well as coronal mass ejections, are becoming more numerous, solar wind turbulence is increasing... and, above all, the field lines are engaged in a particularly chaotic ballet, culminating in a complete reversal of the polarity of the solar magnetic field. Every 11 years, the Sun's north (magnetic) pole becomes its south pole, and vice versa.
To date, no one has been able to determine precisely what triggers this spectacular inversion. Experts believe it is a consequence of internal dynamo processes, the large-scale plasma movements that generate the Sun's magnetic field and determine its behavior. However, we know relatively little about this dynamo. Being able to directly observe a pole at the precise moment when it manifests itself in a particularly spectacular way is therefore a real blessing for researchers.
The best is yet to come
And the icing on the cake is that this observation campaign is going to become increasingly productive. Over the next four years, Solar Orbiter will continue to increase the inclination of its orbit to reach an angle of 33° with respect to the solar equator. It will therefore be able to capture even more complete and detailed images, with all that this implies for future studies on the dynamics of our favorite star.
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