On New Year’s Eve 2023, the sun blasted a huge X flare, the biggest of solar cycle 25 so far. It came from sunspot region AR3536 and measured X5 on the solar flare intensity scale. The eruption produced a wave that rippled across the sun’s face in all directions. It produced a coronal mass ejection, or CME, a great clump of superheated matter that left the sun and traveled outward into our solar system.