Just re-watched Season 3, and I'm reminded how much I love the science. That zero-gravity fire with @Mi55Tipper ...Wow! I used to give talks for NASA about the need for flame research in zero-g, and I did a lot of low gravity research flights myself. That scene was 💯.
@Mi55Tipper Here is what NASA says about doing research on how fires burn in zero gravity: nasa.gov/mission_pages/…
3/ You can see there’s a lot of structure in the physics of a flame in gravity. There are at least 3 regions of different color where different parts of the physics dominate. In gravity, they are arranged vertically from bottom to top. 
4/ Also you can see that the flame gets skinnier as it goes upward. This is the opposite of a stream of water that gets skinner as it goes down. Both are caused by the same effect...
5/ Water goes down because (in gravity) it is heavier than air. A flame goes up because (in gravity) it is lighter than air. Both speed up as they move, so they have to get skinner either down or up. Without gravity that doesn’t happen.
6/ So water just floats in a ball when it is in space. And flames just float in a ball, too! (The gif shows NASA astronaut Don Pettit doing zero gravity water experiments in the Space Station. Full video here: )
7/ Here is a zero gravity flame in a NASA drop tower. It runs out of fuel so the flame dies out, but in the scene with @Mi55Tipper the fuel wasn’t running out so it kept growing instead. (credit: Axelbaum/WUStL/NASA )
8/ Note how the flame exists as a sphere. That’s because there is no preferred up or down without gravity. But this allows other behaviors to emerge! See short video of the cool apparatus that made this: (Credit: NASA/FLEX-2experiment in Space Station.)
9/ The reason we need to study flames in zero gravity is because the physics of combustion are very complicated & not completely understood. Here is a seminal paper by Russian physicist Yakov Zel’dovich. (His son Boris Zel’dovich was on my PhD committee.) ntrs.nasa.gov/archive/nasa/c…
10/ To illustrate how complicated it is, there is a famous simplification of “flame physics” called the Shvab-Zel’dovich Formulation. Note, this is a *simplification* of the equations. (Source: books.google.com/books?id=kdfx5…)
11/ That equation describes what happens as energy and material spread through a flame. Remember that structure I mentioned in the flame? The equations try to explain how that structure develops, because a lot is happening in there!
12/ A problem is that because of gravity, everything wants to start accelerating upwards, so that extra motion smears out some of the physics and makes it impossible to see what is going on inside the flame. That’s why we need to study it in zero gravity.
13/ So anyhow when I saw Naomi Nagata (@Mi55Tipper) facing a zero-g flame my mind was blown. The physics was amazing! And the way she put out the fire! Dannnggg. It was awesome.
14/ And BTW, I discovered the true😉 backstory of Naomi Nagata and why she is a Belter. Tonight I was reading papers about the magnetism of lunar soil and noticed that there was a lunar scientist named T. Nagata in Japan.
articles.adsabs.harvard.edu/pdf/1974LPSC..…
articles.adsabs.harvard.edu/pdf/1974LPSC..…
15/ Takeshi Nagata was a geophysicist. He mostly did polar research but he also studied lunar soil. His wiki article is here: en.m.wikipedia.org/wiki/Takeshi_N…
16/ Mount Nagata in Antarctica is named after him. And Takeshi Nagata did research on how meteorites collect in Antarctica. He found meteorites there and published papers about them. And guess where meteorites come from? ...(wait for it)...
17/ Meteorites come from THE BELT! 🤯😅 They are fragments of asteroids that wandered from the main belt under the perturbing influences of Jupiter & Saturn. So they became near-Earth asteroids and meteoroids and eventually fell into Earth’s atmosphere and a portion landed.
18/ So I’m guessing ;) the backstory of Naomi Nagata is that she is descended from geophysicist, meteorite scientist & Antarctic explorer Takeshi Nagata. He inspired his descendants to continue exploring, so that is how Naomi’s family found themselves in the Belt.
19/19 Physicists studying zero-g fires and Antarctic explorers studying meteorites, and how we might inspire the next generation... here’s the summary by JFK, at the end of the Expanse season 4 trailer.
