You may be preoccupied with Tuesday's asteroid 2005 YU55 flyby, but there's another astronomical event currently unfolding in the solar system. Zoom out from the Earth-moon system for a moment and focus your attention to the surface of our nearest star, nearly 100 million miles away. Yes, that star: the sun.
A few days ago, solar observatories became fixated with a rather big blemish slowly rotating across the surface of the sun. In fact, it wasn't one blemish, it was a cluster of blemishes.