transition said:

beautiful, so cosmic radiation doesn’t have anything to do with it?

There are some quite good high speed camera videos of sprites.

https://m.youtube.com/watch?v=myHDv3Xn2_A

https://m.youtube.com/watch?v=LW3D033TKwY

https://m.youtube.com/watch?v=i3StAXEbGSM

Just having a weird, off the wall, totally mad idea.

Looking at the sprite videos, there is a volume flash, rapidly followed by what looks like almost exactly like rain pouring down through the Earth’s atmosphere.

But when you look at the timeframe, less than a second at 10,000 frames per second, and the distance this rain travels, 20 km or more, what sort of rain can fall under the action of gravity at a speed of in the rough ballpark of 10,000 km/second? That’s too fast even for interstellar speeds, while still being noticeably slower than the speed of light at 300,000 km/second.

Interstellar dust would hit at a speed no faster than about 200 km/s, 400 km/s at absolute maximum. And its direction would be at a random angle, not downwards like rain.

So, given prompting from transition’s question.

Hence this really weird thought popped into my head. What if what we’re seeing is like a Wilson cloud chamber, but actually seeing Dark Matter falling through the atmosphere.

What would that imply?

It would imply that dark matter can and does interact with normal matter.

It would imply that the acceleration due to gravity for dark matter is massively larger than for normal matter, of the rough order of ten thousand times more.

It would imply that dark matter is friable, it breaks up into smaller pieces.

That initial volume flash suggests that dark matter is ever weirder than that, possibly non-localised.

I’m definitely not prepared to accept that explanation at face value, but what other explanation is there for the high speed rain seen in these videos?

mollwollfumble said:

transition said:

beautiful, so cosmic radiation doesn’t have anything to do with it?

There are some quite good high speed camera videos of sprites.

https://m.youtube.com/watch?v=myHDv3Xn2_A

https://m.youtube.com/watch?v=LW3D033TKwY

https://m.youtube.com/watch?v=i3StAXEbGSM

Just having a weird, off the wall, totally mad idea.

Looking at the sprite videos, there is a volume flash, rapidly followed by what looks like almost exactly like rain pouring down through the Earth’s atmosphere.

But when you look at the timeframe, less than a second at 10,000 frames per second, and the distance this rain travels, 20 km or more, what sort of rain can fall under the action of gravity at a speed of in the rough ballpark of 10,000 km/second? That’s too fast even for interstellar speeds, while still being noticeably slower than the speed of light at 300,000 km/second.

Interstellar dust would hit at a speed no faster than about 200 km/s, 400 km/s at absolute maximum. And its direction would be at a random angle, not downwards like rain.

So, given prompting from transition’s question.

Hence this really weird thought popped into my head. What if what we’re seeing is like a Wilson cloud chamber, but actually seeing Dark Matter falling through the atmosphere.

What would that imply?

It would imply that dark matter can and does interact with normal matter.

It would imply that the acceleration due to gravity for dark matter is massively larger than for normal matter, of the rough order of ten thousand times more.

It would imply that dark matter is friable, it breaks up into smaller pieces.

That initial volume flash suggests that dark matter is ever weirder than that, possibly non-localised.

I’m definitely not prepared to accept that explanation at face value, but what other explanation is there for the high speed rain seen in these videos?

Electron cascade, the same way electricity travels through metals at high speed.

Michael V said:

Electron cascade, the same way electricity travels through metals at high speed.

But what triggers it? This is one frame from the first video.

mollwollfumble said:

Michael V said:

Electron cascade, the same way electricity travels through metals at high speed.

But what triggers it? This is one frame from the first video.

OK, I’ve convinced myself that this has nothing to do with dark matter. The properties of such dark matter would have to be far too weird to be plausible.

I’ve confabulated two mysteries into one. The best example I know of this is where the ancients mixed together the mystery of how a snake moves smoothly across the ground and how the Sun moves smoothly across the sky to conclude that the sun was pushed across the sky by a snake.