Translunar injection explained

12:18>> Um and this is one of the situations where production there's very few people who make it to production. >> Yeah. Yeah, four four four people made it to production here, right? And it's like we better give them a camera that we know is going to work. So, the astronauts also have the newer Nikon Z7 or sorry, the Z9. But NASA was like, "No, no, no. This is going to be your primary because we know it works. The low light sensitivity is good and we just know that the the sensor electronics are robust to whatever random crap you're going to be thrown at." >> Yes. Yes, we're we don't want to test new stuff uh on the first try. >> No. No, not at all, right? And so now

12:58let's finally get to the photographs because these were just absolutely amazing. The first set of photographs that I'm going to talk about is right after the trans lunar injection burn. So, this was Artemis did a high elliptical orbit around the Earth to check that everything was working and then they powered up their engines, which is right down here. >> Yes. >> Did a trans lunar injection burn so they gained velocity and now they're going straight to the moon. >> I I want to pause here really quick because I I just want to when you talk about the translunar injection burn, just to help people understand, we touched on this briefly in our recap of Artemis, but I think it's helpful when you What do you mean when you say that?

13:41>> So, what I mean when I say that is Artemis, like any other object out in space, is orbiting the Earth because it's got some velocity, and so the Earth keeps pulling on it, and as it pulls on it, the Earth pulls back, and you're going to do some kind of orbit. Now, before the translunar injection burn, we had a high elliptical orbit where we went, I think something like 35,000 mi, which is like a sixth of the way to the moon, just to test out all of the components here because this stuff hasn't been tested on manned crew expeditions. As we're returning, >> and we're returning because we're being pulled back to Earth by the Earth's gravity. >> by the by the Earth's gravity. Now, as we're returning, we're going to gain speed.

14:21When we're closest to the Earth, if we burn all of the engines that are down here, we're going to gain velocity, and when we gain velocity, that means we're going to gain kinetic energy. From undergrad physics, we know that, you know, energy is always balanced. So, when we gain kinetic energy here, as we move farther away, we're going to attain a higher height. Right? It's like if we if we throw a baseball at a high velocity, it's going to reach a higher height. That's I mean, that's how home runs work, right? You got to really get the sweet spot and really knock that thing out of the park. How do we do that? The the velocity of the baseball right after it hits the bat has to be really high, and the angle has

15:03to be exactly right to go all the way into the stands. >> Which is why we don't see home runs on these new 40-mph pitches that we've seen coming. >> Oh, I haven't >> Cuz it's mostly because people can't hit it. >> Yeah. >> Yeah, exactly. That's probably why. Must have been the Blue Jays. No. >> I I'm going to leave that one where it is. >> Yeah, yeah, yeah. There's a Look, it is what it is. Um so, I What What was I saying? It was The idea is we want to attain a high velocity when we're leaving Earth. >> Right. >> And that way we can attain a high height. Height meaning a distance from the Earth. And that's what that trans inject translunar injection is doing.

15:44There's engines at the back of this white part here that are going to expend all of their fuel and they're going to attain that high velocity so that we're throwing this baseball, this entire thing, all the way to the moon and then it's going to come back. >> And not to be pedantic, but when you say velocity, you're saying we're just turning it the dial to 11 and saying let's go as fast as possible that direction at a very specific time as we're coming back from that high elliptical orbit. Yeah. And so, we're just putting a bunch of juice, thrust, through the back that's going to shoot us off at a moment of also where the Earth's gravity

16:24and how it's impacting the craft is going to assist us in getting more height than we otherwise would if we were just putting that amount of thrust behind us without the assistance of Earth's gravity. >> Yes, I mean, we're we're fighting Earth's gravity is the thing, right? We We used Earth's gravity to gain that velocity back. >> Yes. >> And then and then now we're doing that burn to gain more velocity using the Oberth effect and then we're going to get even higher. >> Got it. >> Right? That's the idea. It's like It's like when the ball bounces back, as it's bouncing back, we like push it even more, you know? And then and then it's going to go even higher. >> Yep. >> Right? That's the idea. It's kind of like if you bounce the ball on a

17:05trampoline, the trampoline is this translunar injection burn in some sense. You know what I mean? >> I just wanted to harp on that a little bit because there has been some discussion and I think a little bit of confusion about the intersection between Earth's gravity, the craft, what does it mean that it's falling back to the Earth? What do we mean by escaping that gravity? So, that I think that's really helpful. >> Yeah. And so, if we go back to photo number nine, if you don't mind. >> Yes. >> Um these are two photos that were taken