This clever image is actually two solar eclipses stacked atop one another. The bottom half of the image shows the sun‘s corona — its wispy, dramatic outer atmosphere — during the a 2017 total solar eclipse, and top half shows a 2023 total solar eclipse. In both, the corona has been unwrapped from around the sun’s circumference and project instead into a rectangle.
The 2017 eclipse took place near the minimum of the sun’s solar cycle and appears relatively tranquil. The 2023 eclipse, in contrast, came near solar cycle’s maximum and shows a far more chaotic and turbulent environment. Notice the bright pink solar prominences dotting the mid-line and the field of shadowy plasma loops above them. (Image credit: P. Ward; via APOD)