So I was watching this video of a talk given by the creators of the game Kerbal Space Program. The video is more or less about game development, but this part (link should go right to the moment but just in case the timestamp is 25:14) hit me like a ton of bricks.
"No one really knows what re-entry effects look like. There's a lot of images on the internet if you just look for it, but you can see that of all of these they're all artists renderings. You can't find like a really nice picture of what the re-entry effect actually looks like."
This video was posted to youtube in 2013, of a talk recorded earlier than that, about a game development process that happened even before then. But I started searching online and sure enough, I can only seem to find artists' renders of re-entry effects. Some of them are so well done that they look photo-realistic, but they're still renders.
Plasma wind tunnels have been built, and I can find video demonstrations of these and the effect looks more or less like our popular conception, but I'm having trouble finding technical specifications that assert that the simulated conditions would look the same.
I know that gas composition can have significant impact on plasma appearance so for all I can confirm, these plasma wind tunnels are only worried about re-creating the pressure and temperature effects as easily as possible but the actual upper atmosphere would look different.
To that end, I found this other video, also from a ESA plasma wind tunnel experiment, and the colors look A.) quite varied! and B.) quite different from the popular conception - lots of greens and purples.
My question is two-fold:
- Is this still accurate, or have we ever actually captured photographic evidence of what re-entry effects look like for real spacecraft re-entering the atmosphere?
- If we haven't (understandable! It's not like we're re-entering multiple spacecraft in formation) then how certain are we that the popular conception of a fiery orange plasma is what re-entry would look like to the human eye?