How these two probes are helping researchers understand solar wind

In Parker’s first close approach to the Sun, it observed that the solar wind near the Sun was indeed abundant with Alfvén waves.

Our Sun drives a constant outward flow of plasma, or ionized gas, called the solar wind, which envelops our solar system. Outside of Earth’s protective magnetosphere, the fastest solar wind rushes by at speeds of over 310 miles (500 kilometers) per second. But researchers haven’t been able to figure out how the wind gets enough energy to achieve that speed – until now.