A second giant “hole” has appeared on the surface of the sun, and scientists fear that it could knock out satellites and radio technology.

The hole, which is said to be 20 times larger than Earth, is unleashing 1.8-million-mile-per-hour solar winds toward the planet and will impact on Friday.

The first hole – 30 times the size of Earth – was spotted on March 23, which released solar winds that triggered stunning auroras as far south as Arizona.

Both holes were captured by NASA’s Solar Dynamics Observatory.

The US space agency said that Coronal holes are magnetically open areas that are one source of high-speed solar wind. “They appear dark when viewed in many wavelengths of extreme ultraviolet light. At times, the solar wind can generate aurora at higher latitudes on Earth.”

The holes’ effects are usually harmless, although satellite communications and high-altitude radio transmissions can sometimes be temporarily disrupted.