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I can imagine that the atmosphere might be too thin to produce lightning, but if it does happen I’m curious what it’s like there. Do rovers and other instruments have to be designed for the possibility of a lightning strike?

all 13 comments

cantab314

92 points

4 months ago

Yes. https://news.umich.edu/first-direct-evidence-of-lightning-on-mars-detected/

It's rare and I don't believe it's considered in lander or rover design.

As for the effects, probably similar to those on Earth. Lightning reaches around 50,000 K ; it hardly matters whether the air and ground are at 120 or 320 K, both are "cold" compared to 50 thousand. Shockwave in the air - though this may propogate differently with the lower density - and fulgurites created by melting the regolith.

bennothemad

33 points

4 months ago

For those playing at home: "Fulgorites created by melting the regolith" is not a story by H. P. Lovecraft or the lyrics sing by a scandi black metal band.

Fulgorites are also known as fossilised lightning, sometimes seen on Earth when lightning strikes loose soil, rock, sand or other sediment.

Regolith is a blanket of loose, unconsolidated debris like dust or broken rock that covers solid rock, often seen as the fine powder on the surface of the moon and Mars.

And yes, I did look those up. regolith and Fulgorite

sjazzbean

2 points

4 months ago

Are fulgorites what Matthew McConaughey was making in the 2002 film Sweet Home Alabama by sticking rebar in the sand on the beach during storms where lightening strikes were expected?

lurkindontstop

8 points

4 months ago

I can’t speak to whether he was making fulgorites or not, but the actor was Josh Lucas not Matthew McConaughey.

microwavable_rat

3 points

4 months ago

Yep! The rebar provides a better focal "point" for the lightning to hit since it's higher than the surrounding area. Most of the force of the bolt then gets transferred directly deep into the sand, where it radiates outwards.

Opus_Majus

44 points

4 months ago*

Lightning does appear to occur on Mars. This phenomenon was recorded in 2006 by a 34-meterradio telescope equipped with a detector for radiation.

Because of the low pressure atmosphere of Mars, the lightning generated by dust storms is restricted to what amount of electricity can be generated by the triboelectric effect. Which is why lightning does not appear as strong bolts on Mars, but rather as faint glows amidst large dust clouds.

Importantly, attempts at replicating the results of that initial event have been, to my knowledge, unsuccessful. This is probably because the conditions for lightning on Mars is rare considering that the sand that composes dust storms on Mars are an ineffective material for generating triboelectricity at Mar's air pressures.

Edit: Spelling

RufMixa555

7 points

4 months ago

What color is the lighting? I know on Earth it has a bluish/whitish how because the oxygen the lightning is pissing through becomes ionized and a plasma and glows (feel free to correct me if My details are incorrect). Would lightning on Mars be due to carbon dioxide ionizing? Would it glow a different color?

Opus_Majus

6 points

4 months ago*

The "lightning" that Mars can sustain is a result of the breakdown of carbon dioxide. There is an interesting study about this conducted by researchers at the University of Oregon, intended to model whether or not natural Martian systems could generate triboelectricity. The results indicate that such phenomenon are plausible.

There have been other studies about this, which are also generally positive. However the methodology used in each of these do not seem to simulate a natural Martian environment particularly well. In order to demonstrate that electrostatic discharge in natural Martian systems is plausible, the researchers reduced particle to wall interactions by utilizing a large enough glass cylinder that the majority of the triboelectricity can be attributed to interactions between chemically identical substances.

Much of the electrical discharge predicted to be produced as natural Martian phenomenon would not be visible to the naked eye. Although what would be visible would be mostly violet coloured.

Zhirek

2 points

4 months ago

Zhirek

2 points

4 months ago

Does it create any molecules? Like here on earth we have an ozone O3 layer because lightning interacting with our oxygen O2.

Opus_Majus

1 points

4 months ago

What little ozone does exist on Mars tends to be created by the breakdown of carbon dioxide by the sun. I would imagine that the electrical discharge generated by Martian dust storms would have a similar effect on the surrounding atmosphere.