This image, snapped by the Japanese probe Hinode on February 1, looks way more terrifying than it actually is. Most of the top half of the Sun seems to have fallen into a massive black hole, but it's not quite that dramatic. It's actually a coronal hole, a gigantic opening that allows the Sun to vent excess gas. Still, I'd feel a lot better about this if there wasn't another gigantic hole down at the Sun's south pole.
NASA explains just what we're looking at here:
On February 1, the Hinode satellite captured this breathtaking image of a coronal hole, seen in the top center of the image. (A polar coronal hole can also be seen at the bottom of the image.) A coronal hole is an opening in the sun's magnetic field through which gas can easily escape into space. The holes are relatively cool in temperature as compared to the active regions nearby — such as the bright region on the lower left portion of the solar disk — the cooler temperature is one of the reasons for the darker appearance.
You can see the full image, which reveals the second hole down at the pole, over at NASA's site.