A recent geomagnetic storm produced stunning aurora displays over northern China, lighting up the starry sky. 

The appearance of an aurora results from a fascinating interaction between solar activity and Earth's magnetic field. 

Starting at 8 a.m. on Wednesday, a geomagnetic storm was detected, with the real-time global geomagnetic activity index (Kp) reaching as high as 9.

The geomagnetic storm was mainly triggered by a solar eruption that occurred on Monday afternoon. A coronal mass ejection (CME) carried solar energy toward Earth, and the connection between the magnetic fields of the sun and Earth sparked the storm.

As the solar material descended further, it interacted with Earth's upper atmosphere near the poles, ultimately giving rise to the stunning auroras.