Private rocket & balloon footage is out there as well, but you have to search bitchute/rumble because it's strictly censored off of youtube.
The sun is right up there chilling, not far away at all.
Discussion
Just stop. Go out and get yourself a huge telescope, even if you just rent it.
I've owned a few telescopes, including the classic 15" dobson. On it there were two kinds of filters you could attach, one that made the sun look like a big yellow ball with just a few black spots, and the H-Alpha filter, which made it darker and look like that conglomerate image you showed. It was filtering out different light wavelengths but let you see more detail.
You can do this yourself. And something else you can do yourself is watch a venus or mercury transit and calculate the distances involved between all parties. It isn't even rocket science, it's just science.
is there an explanation for why the sun moves at the same speed across the southern hemisphere during their summer, as it does across the northern hemisphere during their summer ?
There's nothing anyone can say to convince a flat earther than we live on a globe in space. But in 5 years space tourism will become frequent and then they will have to say that we live in a simulation.