An enormous triangular hole in the Suns corona was captured earlier today by NASAs Solar Dynamics Observatory, seen above from the AIA 211 imaging assembly. This gap in the Suns atmosphere is allowing more charged solar particles to stream out into the Solar System and toward Earth as well.
Normally, loops of magnetic energy keep much of the Suns outward flow of gas contained. Coronal holes are regions sometimes very large regions, such as the one witnessed today where the magnetic fields dont loop back onto the Sun but instead stream outwards, creating channels for solar material to escape.
The material constantly flowing outward is called the solar wind, which typically blows at around 250 miles (400 km) per second. When a coronal hole is present, though, the wind speed can double to nearly 500 miles (800 km) per second.
Increased geomagnetic activity and even geomagnetic storms may occur once the gustier solar wind reaches Earth, possibly within two to three days.
The holes appear dark in SDO images because they are cooler than the rest of the corona, which is extremely hot around 1,000,000 C (1,800,000 F)!
Heres another image, this one in another AIA channel (193):
Keep up with the Suns latest activity and see more images on NASAs SDO site here.
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