Solar Orbiter Captures First-Ever Images of Sun’s Polar Regions

The Solar Orbiter spacecraft has achieved a groundbreaking milestone by capturing the first images of the sun’s poles, facilitating scientists’ quest for a deeper understanding of our star, its magnetic field, the dynamics of its 11-year solar cycle, and the solar wind.

On Wednesday, the European Space Agency unveiled images taken in March with three onboard instruments of the Solar Orbiter. These images depict the sun’s south pole from a distance of approximately 40 million miles (65 million km) during a peak period of solar activity. Data from the north pole are still being sent back to Earth.

Launched in 2020 from Florida, the Solar Orbiter was developed in partnership between ESA and NASA.

Previously, all observations of the sun had been made from the same perspective—looking directly at its equator from the ecliptic plane, which is the orbital plane of Earth and most other planets in the solar system.

The Solar Orbiter achieved a unique angle by using a flyby around Venus in February, allowing it to view the sun up to 17 degrees below the solar equator. Additional flybys planned for the future are expected to enhance this view to over 30 degrees.

“The best is yet to come. What we have seen is merely an initial glimpse,” remarked solar physicist Sami Solanki from the Max Planck Institute for Solar System Research in Germany, who leads the Solar Orbiter’s Polarimetric and Helioseismic Imager team.

“The spacecraft first observed the south pole, followed by the north pole. Data from the north pole will be arriving in the upcoming weeks or months,” Solanki stated.

The Solar Orbiter is collecting data on various phenomena, including the sun’s magnetic field, its activity cycle, and the solar wind—a continuous, high-speed stream of charged particles flowing from the sun’s outer atmosphere, filling interplanetary space.

“We are uncertain about the discoveries that await us, and it is likely we’ll uncover phenomena previously unknown to us,” said solar physicist Hamish Reid, co-leader of the Solar Orbiter’s Extreme Ultraviolet Imager instrument at University College London.

The sun is an immense sphere of hot, electrically charged gas that generates a potent magnetic field as it moves. This magnetic field undergoes a reversal from south to north every 11 years, a process known as the solar cycle.

This magnetic field causes the formation of sunspots, which are cooler areas on the solar surface that appear as dark spots. At the start of a cycle, there are few sunspots, but their numbers rise as the cycle progresses, eventually restarting the process.

“To effectively comprehend this solar cycle, we need to understand what’s happening at both the sun’s poles,” Reid explained.

With a diameter of around 865,000 miles (1.4 million km), the sun is more than 100 times larger than Earth.

“While Earth has distinct north and south poles, the Solar Orbiter’s measurements reveal that both north and south polar magnetic fields are currently present at the sun’s south pole, which occurs during the peak of the solar cycle when the magnetic field is set to flip. In the coming years, as the sun approaches solar minimum, we anticipate a more organized magnetic field around the sun’s poles,” Reid noted.

“The images and animations from the polar regions highlight the chaotic state of the sun’s magnetic field at this phase of the solar cycle—characterized by high solar activity and maximum cycle,” Solanki added.

The sun is situated about 93 million miles (149 million km) away from Earth.

“The data that Solar Orbiter collects in the next few years will assist modelers in forecasting the solar cycle. This information is crucial for us on Earth, as solar activity can lead to solar flares and coronal mass ejections that may disrupt radio communications, destabilize power grids, and contribute to spectacular auroras,” Reid explained.

“Solar Orbiter’s new vantage point, away from the ecliptic, will also provide a more comprehensive view of how the solar wind expands to create the heliosphere—a vast bubble surrounding the sun and its planets,” Reid elaborated.

Earlier, in the 1990s, a previous spacecraft named Ulysses flew over the solar poles.

However, Ulysses lacked optical instruments like telescopes or cameras, meaning it could only detect the solar wind passing directly by the spacecraft, without capturing visual images of the sun itself, according to Solanki.