Just when we think we've seen every kind of optical illusion possible, another mind-bending/blowing/frying example comes along. And this delightful offering comes courtesy of none other the the sun itself.
The official NASA Twitter account has shared an image of the sun appearing to smile. It's all thanks to dark patches on the sun called coronal holes, regions where "fast solar wind gushes out into space" (presumably after the sun has eaten a large curry). And yep, it really does look like the sun is giving us a good old grin. Maybe the 'Sun With Face emoji' isn't so cartoonish after all. For more awesome examples, take a look at the best optical illusions of all time.