Solar Orbiter detects high-speed magnetic waves driving solar wind

The Solar Orbiter spacecraft has identified rapid, high-frequency magnetic waves in the Sun’s polar coronal regions that were previously undetected by older instruments. A study led by researchers from Peking University, published in the National Science Review, suggests these vibrations may be responsible for accelerating solar wind particles to speeds of hundreds of kilometers per second.

The discovery was made possible by the superior resolution and speed of the Extreme Ultraviolet Imager (EUI) on Solar Orbiter. While NASA’s Solar Dynamics Observatory (SDO) captured images every 12 seconds with a spatial resolution of approximately 1,100 km per pixel, the EUI captures images every five seconds with a precision of 420 km per pixel.

Using the Northumbria University Wave Tracking (NUWT) program to analyze data from September 2021, researchers found that the EUI detected 2,318 wave events in solar plumes, compared to only 560 detected by the SDO. This represents more than four times the number of events. The higher frequency of these waves—38% of which had wavelengths shorter than 100 seconds—indicates they transport approximately 2.6 times more energy than previous models had estimated.