Scientists from the Institute of High-Current Electronics of the Siberian Branch of the Russian Academy of Sciences in Tomsk have made a breakthrough in the study of atmospheric phenomena. They managed to record "runaway" electrons — ultrafast charged particles — in laboratory conditions for the first time while simulating a rare natural phenomenon known as red sprites.
Red sprites are impressive luminous columns up to 50 kilometers high that occur in the upper atmosphere during powerful thunderstorms. Until now, such electrons have only been detected in ordinary lightning at altitudes up to 15 kilometers.
To conduct the experiment, scientists created a special setup that simulates the conditions of the mesosphere — an atmospheric layer at an altitude of 50–90 kilometers. The experiment was based on a quartz tube with rarefied air, where a dense plasma was created using electrodes and high-voltage pulses. Plasma jets up to two meters long were formed in the tube — miniature copies of natural sprites.
A special collector recorded runaway electrons at the boundary of the plasma and jets. These particles accelerate in the electric field, gaining more energy than they lose when colliding with molecules. The electrons were ahead of the plasma jet front — just like in natural sprites, where they move up streamer channels.
The discovery has practical significance. Runaway electrons enhance the glow of sprites and create dangerous X-ray radiation that threatens satellites above 200 kilometers. They also generate interference that disrupts radio communications.