A lucky alignment of two sun-studying spacecraft may have finally solved a decades-old solar mystery.
Data from NASA’s Parker Solar Probe and the European Space Agency’s Solar Orbiter suggest that plasma waves known as Alfvén waves inject energy into the solar wind as it leaves the sun’s outer atmosphere, potentially explaining why the solar wind is so much hotter and faster than heliophysicists expect, researchers report August 29 in Science.
The findings provide “a very strong indication that Alfvén waves can heat and accelerate the solar wind,” says Jean Perez, a plasma physicist at the Florida Institute of Technology in Melbourne who was not involved in the study.