Solar Dynamo: “Solar Orbiter” takes First-ever Images of the Solar pole

For a better understanding of solar dynamo, it is imperative to study solar poles, however all observations of the Sun so far were made from about solar equator. It was not possible to image solar poles due to limited view from the ecliptic plane. Recently, trajectory of “Solar Orbiter” spacecraft was successfully tilted 17° below the Sun’s equator, which allowed the probe to take first-ever images of the Sun’s south pole during its flyby of the Sun in March 2025 at a time when the Sun was at the maximum of its current solar cycle and when its magnetic field was undergoing a flip towards pole reversal. Analysis of the present results and further studies of the polar regions of the Sun in future from inclined orbits would help better understanding of solar wind towards an accurate prediction of space weather.

Dynamo is generally thought as a device that converts mechanical energy into electricity however it also means magnetic field generator. In astronomy, it refers to how celestial bodies like Earth or Sun generate their magnetic fields. In the case of Earth, constant flow of liquid iron within its outer core generates magnetic field that protects life forms and technical infrastructure from powerful ionising solar winds. Earth’s magnetic field undergoes pole reversal after an average interval of about 300,000 years when magnetic north and south poles swap locations. Last magnetic pole reversal in Earth took place about 780,000 years ago.

Sun’s magnetic field is much more intense and dynamic as it is a large ball of churning plasma. Movements of hot charged gases within the interior, especially from convection zone to the photosphere generate strong magnetic fields, which unlike Earth’s field, change dramatically in a cyclical manner over the course of few years displaying sunspot cycle and magnetic pole reversal periodically every 11 years. These changes determine solar wind and space weather that has very strong bearing on life forms and technological infrastructure on Earth, hence the need of better understanding of solar dynamo.

Improved understanding of solar dynamo requires observation of solar poles through spectroscopy and polarimetry. However, solar poles have never been observed so far due to limited view available to the space probes which are placed within the ecliptic plane, a flat disc around the Sun in which Earth, the other planets, and all space probes orbit the Sun. All the images of the Sun were taken from around solar equator. The ecliptic plane is tilted by 7° relative to equator of the Sun; however, this is not enough for a clear view of solar poles. Earth-based telescopes also suffer same limitation. Fortunately, this limitation has recently been overcome.

In February 2025, the “Solar Orbiter” probe of European Space Agency was able to tilt its orbit by 17° below the solar equator outside the ecliptic plane following a slingshot flyby of Venus. This was enough to catch a direct view of the solar south pole. In March 2025, the probe successfully took several images of the Sun’s south pole.

These images of the south pole of the Sun were taken at a time when the Sun was passing through the maximum of its current solar cycle and when its magnetic field was undergoing a flip towards pole reversal. The images clearly show presence of both north and south polarity at the south pole indicating flip. As a result, the south pole appears in a state of turmoil. Single polarity should slowly build up following completion of reversal. The new images should come handy in understanding the mechanism of how polarity builds up.

The Solar Orbiter instrument also made measurements of movement of solar material within a specific layer of the Sun which can reveal how ionised particles escape the Sun in the form of solar wind. Such measurements from the polar regions would help better understanding of solar wind.

The analysis of results of the first observations of polar region of the Sun from newly inclined orbit of the probe and similar future studies would immensely enhance our understanding of the Sun’s magnetic field, the solar wind, and space weather.

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References:

Harra, L., Müller, D. Solar orbiter: a short review of the mission and early science results. Astrophys Space Sci 370, 12 (2025). https://doi.org/10.1007/s10509-025-04400-3