NASA's Solar Dynamics Observatory recently captured an amazing sight. The American space agency has discovered a massive black hole that is slowly spreading across the surface of the sun.

This is, in fact, an astronomical phenomenon called the coronal hole. The appearance of the coronal hole has captured the interest and gaze of spectators as it resembles the appearance of that an apocalypse. It might sound dangerous, however, it is completely harmless. The researchers believe that the coronal hole over the sun may only cause a few cosmic inconsistencies, but otherwise, it is completely harmless.

A coronal hole is a spot in the corona of the sun, which is a type of a plasma layer around the sun. A coronal hole is low-density in nature and acts as an opening between interplanetary space and the magnetic field of the sun. It creates a stream of strong solar winds and the coronal matter is ejected outwards from the hole.

The coronal hole appears dark in extreme ultraviolet (EUV) imagery because the plasma structures visible in such imagery are not present. According to Robert Steenburgh of the National Oceanic and Atmospheric Administration's Space Weather Prediction Center in Boulder, Colorado, the coronal hole is not visible in all types of imagery, including white light images of the sun.

Typically, coronal holes are not a matter of concern despite their unusual and apocalyptic appearance. These are a natural phenomenon that occurs sporadically. However, the researchers believe that some of its effects can be "downstream" toward the other side of the solar system.

Downstream, coronal mass ejection (CME) takes place. The phenomenon includes the flow of billions of tons of plasma from the sun to Earth. It creates huge geometric storms that may affect the airline communication, radio signals and GPS. For example, geomagnetic storms made Hydro-Québec power network crash in 1989. The effect lasted for more than nine hours and affected around 6 million people.