New research finds cosmic rays hitting the atmosphere cause of the ignition of lightning
New research has now found that the shower of energy produced when a cosmic ray hits the atmosphere could be a major cause for the ignition of lightning in thunderheads.
You can read the paper here. The two graphs to the right are taken from figure 3 of the paper, and show two different lightning events. The colors represent time, going from green (earliest) to blue to yellow and red (latest). The white dot marks the spot where the lightning flash started. From the article above:
We believe that that most lightning flashes in thunderstorms are ignited by cosmic ray showers,” says the study’s lead author Xuan-Min Shao, a senior scientist at the Los Alamos National Laboratory in New Mexico.
…One of the important things about cosmic ray showers is that they contain antimatter–positrons as well as ordinary electrons. The Los Alamos 3D lightning maps contained strong evidence for positrons. Electrons and positrons are bent in opposite directions by Earth’s magnetic field, so they leave opposite imprints on the lightning’s polarization, which BIMAP-3D also measured.
…Positrons clinched the case for cosmic rays. “The fact that a cosmic ray shower provides an ionized path in the cloud that otherwise lacks free electrons strongly favor the inference that most lightning flashes are ignited by cosmic rays,” the authors wrote.
It remains unclear if cosmic rays cause all lightning flashes or just some. Either way, it is a remarkable thing to consider: Cosmic rays are created in distant interstellar and even intergalactic events. The rays take millions, maybe billions of years to reach Earth. And when they do, they produce lightning in thunderstorms!
Hat tip reader Steve Golson.
New research has now found that the shower of energy produced when a cosmic ray hits the atmosphere could be a major cause for the ignition of lightning in thunderheads.
You can read the paper here. The two graphs to the right are taken from figure 3 of the paper, and show two different lightning events. The colors represent time, going from green (earliest) to blue to yellow and red (latest). The white dot marks the spot where the lightning flash started. From the article above:
We believe that that most lightning flashes in thunderstorms are ignited by cosmic ray showers,” says the study’s lead author Xuan-Min Shao, a senior scientist at the Los Alamos National Laboratory in New Mexico.
…One of the important things about cosmic ray showers is that they contain antimatter–positrons as well as ordinary electrons. The Los Alamos 3D lightning maps contained strong evidence for positrons. Electrons and positrons are bent in opposite directions by Earth’s magnetic field, so they leave opposite imprints on the lightning’s polarization, which BIMAP-3D also measured.
…Positrons clinched the case for cosmic rays. “The fact that a cosmic ray shower provides an ionized path in the cloud that otherwise lacks free electrons strongly favor the inference that most lightning flashes are ignited by cosmic rays,” the authors wrote.
It remains unclear if cosmic rays cause all lightning flashes or just some. Either way, it is a remarkable thing to consider: Cosmic rays are created in distant interstellar and even intergalactic events. The rays take millions, maybe billions of years to reach Earth. And when they do, they produce lightning in thunderstorms!
Hat tip reader Steve Golson.