A Coronal Mass Ejection - CME - is a massive burst of plasma shot out of the Sun, which releases an immense amount of charged matter into space. If the CME is ejected in the direction of Earth, interaction with our planet's magnetosphere can cause geomagnetic storms, aurorae and, if large enough, can disrupt electric and telecommunications grids.
The one imaged here was captured on May 26, 2022 and is several times the size of our entire planet.
This image was shot with my telescope using a Hydrogen Alpha filter, which filters out excess light allowing only a very specific wavelenght of light through, revealing the intricate details of the lower atmosphere of the Sun.