One of the largest coronal holes of the year with a diameter of about one million km was formed on the Sun, the Solar Astronomy Laboratory of the Space Research Institute of the Russian Academy of Sciences and ISTP SB RAS reported. Coronal holes are regions in the solar corona where the plasma density and temperature are reduced. They can cause geomagnetic storms and especially colorful auroras on Earth.

One of the largest coronal holes of the year with a diameter of about one million km was formed on the Sun, the Solar Astronomy Laboratory of the Space Research Institute of the Russian Academy of Sciences and ISTP SB RAS reported. Coronal holes are regions in the solar corona where the plasma density and temperature are reduced. They can cause geomagnetic storms and especially colorful auroras on Earth.