in an essay in the journal Sciences A group of astronomers described a possible explanation Thursday night: large particle plumes several hundred kilometers across are shooting out of precisely those sunspots.
Scientists would like to know how the solar wind forms because weather in space also affects Earth. This happens, for example, when the Sun releases not a gentle stream of solar wind, but a powerful blast of charged particles.
And when such a so-called solar storm heads toward Earth, it poses a particular threat to our technology. It can destroy satellites and astronauts on the International Space Station have to hide behind water tanks, otherwise the radiation is dangerous to their health.
About the author
Georg van Hall writes for De Volkskrant about astronomy, physics and space travel. He has published books on everything from the universe to the smallest, most basic elements of reality.
prediction more accurately
On the ground, electricity grids can also become overloaded. “So the power grid operators get a warning and then turn off part of the grid,” says astronomer Jorit Lennarts, director of the Institute of Heliophysics at Stockholm University. “But it costs a lot of money.”
So scientists are more than just curious about how the solar wind and solar storm form. “When you understand this better, you can also improve simulations and models, and perhaps in the long term predict more accurately when such an outburst will occur on the Sun.”
The researchers found evidence of the plumes in measurement data from the Solar Orbiter, a European probe that flies around the poles of our parent star. “These columns are relatively small.” “That’s why you can’t see it from Earth,” says Lennarts, who was not involved in the research. “But it works with the solar orbiter.”
Basic research
According to the authors, the plumes are generated by complex motions of the sun’s magnetic field, which is much stronger in cooler sunspots than elsewhere on the surface. Laertz describes this idea as compelling and shares the authors’ view that such a mechanism could provide an explanation for the solar wind. “But they haven’t fully demonstrated it with these measurements,” he says.
Although the researchers show that the amount of matter flowing from these jets roughly corresponds to the amount of particles in the solar wind, they still have no explanation for the fact that the solar wind is moving much faster than the particles in the solar wind now detected. columns, for example.
Moreover, the plumes are very narrow, while the solar wind spreads out much wider. “This is basic research,” Lennarts says. “It’s very interesting, but the step from this result to concrete predictions of solar storms is still a long way off.”