NASA's Solar Dynamics Observatory is monitoring a dark rift in the sun's atmosphere. The spacecraft's Atmospheric Imaging Assembly (AIA) took this extreme ultraviolet picture just hours ago:
It's a "coronal hole," a vast region where the sun's magnetic field has opened up and allowed the solar wind to escape. Indeed, a solar wind stream flowing from this hole is heading toward Earth, due to arrive on June 7th or 8th.
Source: Space Weather