Right before Christmas, a gargantuan black fissure opened on the Sun. It was shaped like a question mark.

It doesn't really take much imagination to see the dark question mark forming and dissipating across most of the Sun's surface in the animation above.The images that make up the animation were acquired by NASA's Solar Dynamics Observatory spacecraft between Dec. 18 and 22, 2017. And if you're thinking that the question mark is some sort of optical illusion, guess again. The feature is very real: an unimaginably large fissure in the Sun's atmosphere.There's nothing to be alarmed about