Can the lightning breathe in space

Are there lightning bolts out of the blue?

With certain restrictions. So, if the sky is really bright blue, not a cloud far and wide, it would be very unusual if lightning suddenly struck. What there is, however, is lightning without a thundercloud being visible in the immediate vicinity. The emphasis is on "in the immediate vicinity", because it is usually somewhere 10-20 kilometers away. But it may not catch the eye, or there may be a mountain in between, so the lightning really looks like it is out of the blue.

And how do these lightning bolts come about?

There is a statement that was published in the journal Nature Geoscience in 2008. It works like this: The basis for such lightning are initially the same conditions under which other thunderstorms occur. So: There are strong updrafts in a thundercloud. These winds also transport positively charged water particles or ice crystals upwards. As a result, the upper part of the cloud is charged positively, the lower part negatively. And at some point the tension builds up so strong that it discharges in the form of a lightning bolt.

There are several possibilities: The normal lightning bolts that we see, which can also be dangerous for us, are lightning bolts between the cloud and the ground. Here the tension between the lower, negative part of the cloud and the somewhat neutral ground is discharged. In addition, there are also lightning bolts within the cloud, namely between the lower negative part and the upper positive part. And these are now the ones that are of interest to us.

Because sometimes it happens that this discharge between the lower and the upper edge of the cloud is not complete, e.g. because there are not enough positive particles at the top of the cloud to compensate for the negative charge at the bottom. And then two things can happen. Either the lightning bolt then continues upwards above the cloud line. Or: It creates an arc to the earth's surface via a side branch - only ten or twenty kilometers away from the actual thundercloud. And as with normal lightning, thunder can follow.

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