What is the purpose of taking pictures of the sun’s poles for the first time?

On the evening of February 9, in Florida, on the east coast of the United States, an Ariane 5 rocket lifted off from launch pad 41 at Cape Canaveral Air Force Base and launched a spacecraft named “Solar Orbiter”. This is the latest solar exploration project of the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA), helping scientists observe the sun from an unprecedented perspective, and will open a new chapter for human exploration of the sun.

Solar Orbiter is a solar probe jointly developed by the European Space Agency and the National Aeronautics and Space Administration. To date, almost all solar observatories operate on the plane of the sun’s ecliptic. This means that more information collected by scientists is concentrated in the regions above and below the sun’s equator, and little is known about the sun’s poles. With the help of Solar Orbiter, scientists will clearly observe the poles of the sun for the first time, which may help people understand the inner laws of solar activity.

Most of the matter in the sun is high-temperature plasma, and the state, motion and evolution of the sun are closely related to the magnetic field. Sunspots, flares, prominences and other active phenomena are directly dominated by the magnetic field. Therefore, the study of the solar magnetic field is of great significance. Under the action of the magnetic field, the solar activity has an activity cycle of about 11 years. During the maximum solar activity, the surface of the sun is covered with sunspots, the activity intensifies, and sometimes more high-energy particles are ejected. This is the so-called coronal mass ejection. Magnetic storm phenomenon. This phenomenon can damage spacecraft in Earth orbit or interfere with global communications. For example, on July 23, 2012, NASA’s Stereo-A spacecraft was hit by a huge coronal mass ejection; the 1859 Carrington event disrupted the then-American telegraph system for four days. Scientists believe that more powerful geomagnetic storms can disrupt the operation of the ground grid, not only causing power outages across the continent, but also potentially destroying giant voltage transformers within the grid, which may take months or years to repair.

For decades, scientists have been trying to unravel the mysteries of solar activity in order to prepare for geomagnetic storms. But so far, scientists have no reliable way to predict the occurrence of geomagnetic storms. Although researchers have obtained detailed data on the magnetic field in the middle part of the sun from various probes, there is still a lack of knowledge about the magnetic field in the polar parts and how it changes during the stellar magnetic field flip. “The magnetic field at the Sun’s poles cannot be effectively observed on the ecliptic plane, and Solar Orbiter is critical for accurate modeling to predict space weather,” explained Gilbert, director of NASA’s Solar Orbiter program.

By observing the poles of the sun by Solar Orbiter, it may be possible to understand why the sun has a solar cycle of about 11 years. The observed data will allow scientists to more accurately model the Sun, potentially interpreting key information about solar activity such as flares, solar wind, solar magnetic fields and prominences, as well as helping predict corresponding space weather events.

Solar Orbiter will probe the sun from a distance of about 42 million kilometers from the sun, and its temperature will be 13 times that of Earth’s orbit. In the next two years, Solar Orbiter will enter the “cruise phase”, using gravity to repeatedly accelerate between the Earth and Venus. It is scheduled to reach its first perihelion in June this year, about 75 million kilometers from the sun, and It flew by Venus for the first time on December 26 this year.