Are there lightning bolts on Mars?

  • Although the Martian atmosphere is thin, there are many atmospheric phenomena that occur on Mars: storms, dust devils, (carbon dioxide) snow,... Some storms even stir up the atmosphere of the entire planet!


    During Martian storms, is there any lightning and thunder, like what we see during Earth storms? What about in the past, when atmospheric conditions were different, has there ever been any lightning on Mars?


  • While not seen yet, dustdevils on mars could also contain lightning as they generate electric fields close to the breakdown of air on mars.



    "On Earth, with instruments we've measured electric fields on the
    order of 20 thousand volts per meter (20 kV/m)," Farrell says. That's
    peanuts compared to the electric fields in terrestrial thunderstorms,
    where lightning doesn't flash until electric fields get 100 times
    greater--enough to ionize (break apart) air molecules.


    But a mere 20 kV/m "is very close to the breakdown of the thin Martian
    atmosphere," Farrell points out.



    Source: https://science.nasa.gov/science-news/science-at-nasa/2005/14jul_dustdevils




    Paschen curves Source


    Paschen's law reflects the fact that as pressure decreases the mean free path increases, which allows an electron to gain more energy between one collision and the next, making it easier to produce an ionization cascade.


    `+1` This is a good point! I'd never though of it before, but yes these low pressure atmospheres can have much lower breakdown voltages than either vacuum or what we have on Earth! I've added a bit of background, please feel free to roll back or edit further.

    I saw FPGA and "My designs are flying a few hundred km above the earth" in your user profile; there may be some unanswered or insufficiently answered *FPGAs in space!* questions here.

    +1! This is a much better explanation of what I was trying to say with my troublesome "last sentence".

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Content dated before 7/24/2021 11:53 AM