These are radio images of Jupiter's magnetosphere due to synchrotron radiation, as seen through its radio wave emissions.
What is really interesting about the Vajra version of the thunderbolt is the globe in the middle and that it also sometimes has 2 more, 1 on either side. Would a bulbous bit like that really help it as an actual physical fighting weapon?
It is hard to believe that it is pure fluke that the ancient civilisations associated a lightning/thunderbolt weapon with the god of the planet that has the same look.
How did they know what it looked like?
Did they see Jupiters magnetosphere in a more energised state?
Was our own atmosphere different to facilitate them seeing it? Did they see things differently to us?
Did they know this is what the radiation belts, plasma instabilities, synchrotron-radiation of planets looked like, so they associated it with Jupiter?
Or is it all just crazy ancients talking coincidental rubbish and desperate Electric Universe Theory followers leaping onto any 'evidence' that they can?