Explanation: The sun's writhing magnetic fields – caused by the movement of the charged material, known as plasma, it's made of – leads to constant change on timescales from milliseconds to billions of years. We see giant solar eruptions such as solar flares and coronal mass ejections that can last minutes to hours.
Because the Sun continues to 'burn' hydrogen into helium in its core, the core slowly collapses and heats up, causing the outer layers of the Sun to grow larger. This has been going on since soon after the Sun was formed 4.5 billion years ago.
