Sun or moon? From the photo it’s hard to tell. It sure looks like a bright sunny day, but this is the South Pole, where it’s still winter and the sun has not yet returned. That’s the moon lighting up the sky—amazing how bright it can seem. In fairness, it wasn’t any old moon—it was full or close to it, and may even have been a supermoon, closer to the Earth and up to 30% brighter than normal. Just as the sun rises and sets less frequently at the Pole (only once per year), so it is for the moon, which remains up in the sky for about two weeks at a time and then out of view for the same amount of time. That’s when you really need the headlights.