> 440 km/s—"Typical speed of the stepped leader of lightning (cf. return stroke below).[31]" Good one, I didn't think about that one. It means that galaxies ar

> 440 km/s—"Typical speed of the stepped leader of lightning (cf. return stroke below).[31]" Good one, I didn't think about that one. It means that galaxies are travelling lightning fast, literally.