Sun goes dark as giant hole spreads across its surface

A dark mass spreading across the surface of the sun has been discovered by a NASA spacecraft.

The phenomenon was identified as a coronal hole, which poses no real risk to Earth.

NASA reports these holes - which can take up a quarter of the sun's surface - occur due to gaps in the magnetic field.

The holes let heat from the sun's 5,500° C mass to escape into open space.

Extreme temperature differences between the streams and the body of the sun creates the dark mass effect.

The coronal hole was identified by NASA’s Solar Dynamics Observatory (SDO) which has been monitoring the surface of the sun since 2010, the Mirror reports.

NASA states on its website that "coronal holes are the source of a high-speed wind of solar particles that streams off the sun".

While the holes pose no danger to the planet, solar winds can disrupt satellites and communication devices.