ESA unveils new high-resolution solar images
The European Space Agency (ESA) has released 4 new images of the Sun obtained by the Solar Orbiter mission, Kazinform News Agency correspondent reports, citing the ESA.
The ESA-led Solar Orbiter mission studies the Sun using advanced imaging instruments. Among them, the Polarimetric and Helioseismic Imager (PHI) not only captures visible-light images but also measures magnetic field directions and tracks surface movement and speed of different parts of the surface.
This data can then be compared with an image of the Sun's corona taken by Extreme Ultraviolet Imager (EUI) on the same day. EUI images the Sun in ultraviolet light.
The images were taken when Solar Orbiter was within 74 million kilometers of the Sun, requiring multiple high-resolution shots to cover its surface. The spacecraft was tilted and rotated until each part of the Sun's face was imaged.
To obtain the full-disc images presented here, all images were stitched together like a mosaic. The PHI and the EUI mosaic are composed of 25 images each, captured over a period of more than four hours.
PHI's detailed image reveals the Sun's surface as glowing plasma, constantly in motion and emitting most of the Sun's radiation at 4500–6000°C. Beneath, the convection zone churns plasma, giving the surface its grainy appearance. Beneath it, the hot, dense plasma is churned around in the ‘convection zone’ of the Sun, not unlike magma in Earth's mantle. As a result of this movement, the Sun's surface takes on a grainy appearance.
PHI's magnetic map, or ‘magnetogram’, shows sunspots — cooler areas of the surface that appear as dark spots. The magnetic map created by PHI shows that the sun's magnetic field is concentrated in these areas, pointing either outward (redi) or inward (blue).
The speed and direction of movement of material at the Sun's surface can be seen in PHI's velocity map, also known as a “tachogram”: blue for movement toward the spacecraft and red for movement away. It reveals that while plasma generally follows the Sun’s rotation, it is pushed outward around the sunspots.
Finally, EUI's image of the Sun's corona shows what happens above the photosphere: million-degree plasma extends above active sunspots, following magnetic field lines that often connect neighboring sunspots.
