Researchers from University College London (UCL) and George Mason University in Virginia, USA, have identified the exact source of potentially dangerous solar particles ejected from the Sun that could pose a threat to various activities on Earth. The high-energy particles are released from the Sun during solar storms that occur in its outer atmosphere.
These can significantly affect or even threaten life on Earth. Specifically, the particles could not only harm astronauts, aircraft and satellites, but scientists fear that they could one day be hit by a more dangerous and long-lasting disruption.
In 1859, a large solar storm called the “Carrington Event” caused widespread problems with telegraph systemsacross Europe and the U.S. Given our heavy dependence on electricity, a recurring storm of this magnitude could be a much more significant and devastating threat.
Researchers believe they have identified the source of the solar particles, in an effort to better predict when they might strike again.
The scientists' findings, published in the journal "Science Advances," show that the particles have the same "fingerprint" as the plasma found low in the Sun's corona, near the middle region of its atmosphere, the chromosphere.
Co-author Dr Stephanie Yardley, from UCL, said: “In our study, we have observed for the first time exactly solar energetic particles ejected from the Sun come from. Our data supports theories that these highly charged particles originate from plasma that has been trapped low in the Sun’s atmosphere by strong magnetic fields. Once released, these energetic particles are accelerated by explosions that travel at speeds of several thousand kilometres per second. Energetic particles can reach Earth very quickly, within minutes to hours, with these events lasting for days. At present, we can only provide predictions about these events when they occur, as they are very difficult to predict before they occur. By better understanding the Sun's processes, we can improve forecasts so that when a major solar storm occurs, we have time to act to reduce the potential risks."
The researchers made the discovery using measurements from NASA 's WIND satellite , which is located between the Sun and Earth.
In addition, the lead researcher, Dr. David Brooks, from George Mason University, pointed out the following: “Our observations provide a fascinating insight into where the material that produces solar energetic particles comes from in a few events from the last solar cycle. We are now starting a new solar cycle, and once that one begins, we will use the same techniques to see whether our results are generally true or whether these events are unusual. We are fortunate that our understanding of the mechanisms behind solar storms and solar energetic particles is likely to advance rapidly in the coming years thanks to data acquired by two spacecraft – the European Space Agency’s (’s Parker Solar Probe NASA – which are heading closer to the Sun than any other spacecraft.”
