The size of a banana: Scientists reproduce a solar flare in the laboratory

Solar flares are huge plumes of superheated plasma that escape from the Sun at a distance of up to 100 thousand kilometers. These massive plumes are so large that they can engulf our planet several times. To study in detail the nature of these solar phenomena, the researchers created them on Earth.

The crown loop was reproduced in the laboratory of the California Institute of Technology

Researchers from the California Institute of Technology have found out how large flares emit potentially dangerous energetic particles and X-rays into space, simulating solar flares in laboratory conditions. The mini-flare was no bigger than a banana in size, and as much energy was spent on its reproduction as a 100-watt light bulb consumes within a minute. The experience is described in detail by Nature Astronomy.

Comparison diagram of real solar flares (above) and artificial (below). Image authorship: Bellan Lab/Caltech

Two electrodes were installed in the gas-filled chamber. Then a current was applied, which ionized the gas, and formed a plasma string between the two electrodes, which was briefly held in place and supported by the magnetic field of the chamber, and then burst out in a mini-flare. The length of the loop was no more than 20 centimeters in length. The loop was about 10 microseconds. To capture the moment of formation and decay of the mini-flare, a special camera capable of shooting video at a speed of 10 million frames/s was used. The study has confirmed the hypothesis that artificial loops have the structure of a rope, as previously assumed by other researchers. This rope-like structure may play a key role in the birth of huge solar flares.

“If you cut a piece of rope, you will see that it consists of separate threads. Stretch these separate threads, and you will see that they are formed from smaller threads, and so on. It seems that plasma loops work the same way,” explained Yang Zhang, a graduate student at the California Institute of Technology and lead author of the study.

The scientists also noticed a power surge associated with an X-ray flare at the exact moment when the circuit broke. This power surge is comparable to the pressure drop that occurs at the point of narrowing of the water pipe. Charged particles are accelerated to extremely high energies by the electric field from this power surge, and when the energetic particles slow down, X-rays are released.

Earlier we reported on how a giant prominence got on the epic portrait of the Sun.

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