'Alfvén waves': Scientists solve the mystery of solar wind gaining energy after leaving the Sun
Produced by: Tarun Mishra
Long-Standing Solar Wind Mystery Solved
Astronomers have long been puzzled by how the Sun’s solar wind, a stream of charged particles, gains its energy even after leaving the Sun. Recent findings suggest that magnetic "switchbacks," or kinks in the Sun's magnetic field, are responsible for powering the fastest solar winds.
Crucial Alignment of Spacecraft
The discovery was made possible due to a rare alignment in February 2022 between NASA's Parker Solar Probe and ESA/NASA's Solar Orbiter. These spacecraft measured the same solar wind stream within two days of each other, providing unique insights.
Credit: NASA
Key Observations from Parker and Solar Orbiter
Parker Solar Probe detected slower plasma filled with switchback waves near the Sun, while the Solar Orbiter observed a fast-moving solar wind stream that had gained heat and displayed little wave activity, offering a "eureka moment" for scientists.
Credit: ESA
Confirmation of Old Theories
The research confirms a theory proposed over 50 years ago, suggesting that Alfvén waves, in the form of switchbacks, provide enough energy to heat and accelerate the solar wind as it moves away from the Sun.
Credit: ESA
Implications for Space Weather Forecasting
These findings not only solve a long-standing question but also enhance our ability to forecast solar activity and space weather, which is crucial for understanding how the Sun affects Earth.
Broader Impact on Astronomy
The insights gained have wider implications for the study of stellar winds beyond our solar system and could impact our understanding of the habitability of exoplanets across the Milky Way.
Advancing Solar Studies
As scientists continue to explore the Sun's mysteries, this discovery represents a significant step forward in unravelling the complexities of our solar system’s central star and its influence on its cosmic environment.