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Image of the solar flare: This is what it looks like when there is a “storm” on our central star



The consequences of a strong solar flare could also affect Earth in the coming days. The US space agency NASA announced that one of the most violent solar flares in recent years was observed on Friday. During such an eruption, the sun ejects billions of tons of charged particles into space that travel at the speed of light. Such eruptions could disrupt communications waves, power grids and navigation signals, among other things, and also posed a risk to spacecraft and astronauts, it said.

  • A video showing Friday's eruption can be seen here:

  • You can read an interview with an astronomer about the effects of solar storms here: How dangerous is particle rain, Mr. Solanki? 

The sun always goes through phases in which it is sometimes more and sometimes less active. An important clue to their activity are magnetic structures on the sun's surface, which are often associated with sunspots. As if on a kind of solar conveyor belt, huge plasma currents sweep these magnetic fields from near the equator to the solar poles over several years - and thus build up the solar magnetic field that shapes the next solar cycle. At the poles the plasma sinks into the depths and flows back to the equator.

A solar cycle lasts about eleven years. The sun's activity has been increasing again since December 2019, and the maximum particle storms are expected in 2025.

The strongest solar storm hit Earth 14,300 years ago

According to a study in the journal “Philosophical Transactions of the Royal Society,” 14,300 years ago the Earth was hit by an extreme solar storm the likes of which had never been observed with modern measuring devices. The cosmic rays are said to have been more than ten times as intense as in all solar storms of modern times and twice as high as in the last known events of this kind.

Evidence of the massive natural event was provided by several stumps of dead trees in the French Alps. These are remains whose fossilization had not yet been completed, writes the group led by Edouard Bard from the Collège de France in the study. The team analyzed the individual annual rings. They found a huge increase in radiocarbon levels 14,300 years ago.