While people on Earth celebrated the New Year with fireworks, the Sun was quite with very few small flares. Indeed, this image from the Solar Dynamics Observatory shows a huge coronal hole present just after midnight on 1 January UTC.
Coronal holes are regions of the Sun’s corona where the magnetic field reaches out into space rather than looping back down onto the surface. Particles moving along those magnetic fields can leave the sun rather than being trapped near the surface. Those trapped particles can heat up and glow, giving us the lovely AIA images. In the parts of the corona where the particles leave the sun, the glow is much dimmer and the coronal hole looks dark.
Image Credit: NASA