Artemis II splashdown: behind the risks of reentry

[0:00] As Orion comes back into Earth's atmospheres, [0:02] there may be no other part of this [0:04] that is more important than the heat shield [0:07] on the bottom of the space capsule here. [0:10] Why is that so important? [0:11] Because this is coming in at 25,000 miles per hour. [0:16] That means there's going to be a tremendous buildup of heat [0:19] on the bottom of the craft, about 5,000 degrees, [0:22] half the temperature of the surface of the sun. [0:26] Now, this is an ablative shield. [0:28] What does that mean? [0:29] That means it is supposed to erode off [0:32] against all of that intense heat. [0:33] But in the Artemis I mission, [0:36] one of the things they noticed [0:37] was that it was not eroding so evenly. [0:39] That's it right over there. [0:41] And that raised some safety concerns. [0:43] So what they did was reconfigure the exact way [0:46] that they're going to bring this back, [0:47] thinking that that might avoid that problem again, [0:51] or at least mitigate it and allow the craft to slow down, [0:55] slowly pop its 11 different parachutes and doing so get to a speed where it can safely splash down in the ocean with the four astronauts aboard. [1:07] In nearly 24 hours, it will take on extreme heat as it travels up to 25,000 miles per hour. [1:12] Their safe return largely depends on the heat shield located at the bottom of the spacecraft. [1:18] The concern? The heat shield has a flaw, and NASA is aware. [1:23] An identically designed heat shield on the 2022 uncrewed test flight called Artemis I returned damage, pockmarked with divots and cracks. [1:32] But NASA is confident it has the problem under control. [1:37] We start off with CNN's Ed Lavendera, who is live at Johnson Space Center in Houston, where mission control is located. [1:43] And Ed, just walk people through, what's NASA expecting as we kind of head into this final critical stage? [1:48] Well, we are 24 hours, almost 24 hours away from the Artemis II crew returning back to Earth. [1:55] And obviously, all of the teams here on the ground at Johnson Space Center. [1:59] And you can see the view from the Orion capsule, the outside, looking back toward the moon as it continues to get smaller and smaller. [2:05] That capsule gaining speed as it's coming toward the Earth's atmosphere. [2:09] Take a live look inside the capsule, and you really get a sense of what the crew is really undergoing right now. [2:15] And they are going through the final preparations, getting everything ready to get back into Earth's atmosphere in the coming day. [2:23] Over the course of the next day, they'll reconfigure the inside of that cabin so that their seats and their suits are all on properly. [2:28] But there is a great deal of concern about this heat shield. [2:31] There has been a small group of heat shield experts led by a former astronaut who voiced concern about this. [2:39] But NASA officials insist they've done all the analysis, they've done all the testing. [2:44] The astronauts themselves have signed off on this plan before they launched, and they feel confident it will go well. [2:50] But there are still nerves here at Johnson Space Center. [2:55] It's 13 minutes of things that have to go right, is the way I think about it. [2:58] And, you know, I have a whole checklist in my head that we, you know, we're going through of all the things that have to happen. [3:06] You know, the forward bay cover has to come off, the drogues have to come out, the main chutes have to deploy, the reefing systems have to cut. [3:13] And we have to get the touchdown angle alignment correct and then hit the water correctly. [3:19] It's impossible to say you don't have irrational fears left, right? [3:23] But I would tell you I don't have any rational fears about what's going to happen. [3:28] We've done the work we need to, and we have full confidence in the team, the recovery team, the flight control team, analysis of the work we did. [3:35] Phil, if you take a look at the picture from Artemis I and what that heat shield looked like after it went through the Earth's atmosphere, [3:41] you can see just the strain and the test that these capsules are put under as they go through these extreme conditions. [3:47] So this will be a very tense moment, 13 minutes. [3:51] There will be six minutes, Phil, where that crew is in blackout, so you can imagine the intensity in that mission control. [3:57] And we know that family members will be in the viewing area behind mission control watching this moment unfold, [4:04] waiting to hear their voices come back on the communication system once they come through the Earth's atmosphere. [4:11] So this is happening just a little over 24 hours from now. [4:15] I want to bring in former NASA astronaut, retired U.S. Air Force Colonel Terry Burtz. [4:19] Terry, really appreciate your time. [4:20] You know, NASA says the Artemis II reentry trajectory has been modified with the goal of avoiding the conditions that we've been talking about, [4:28] the ones that caused Artemis I's heat shield to crack. [4:31] Despite that, do you have concerns about the unknown risks here related to the heat shield? [4:38] You know, there's always a concern when you're landing, but I feel confident in this. [4:42] I have a friend who, a fellow astronaut who was part of that investigation team. [4:46] He dove into the details. [4:48] He's a highly trained engineer, and he looked at it, and he was comfortable with it. [4:52] So on the first unmanned test a few years ago, the capsule came back at a very low angle, [4:58] and it kind of skipped off the atmosphere, and it spent a long time in that high-speed, high-heat period. [5:06] And what they're doing now is they're coming back steeper. [5:08] So it'll be a quicker descent into the Earth's atmosphere. [5:13] The heating will actually get a little bit hotter, but it'll last for less amount of time. [5:17] And they think that shorter time will be better for the heat shield. [5:20] And then in the future, for future heat shields, they're going to redesign it. [5:24] But, you know, I'll tell a quick story. [5:26] When I came back on the Soyuz, my crewmate, Scott Kelly, he had done it before, and the only time I had landed was on a space shuttle. [5:33] And he said, hey, you're going to think you're going to die because it's such a crazy ride, but don't worry, you're not. [5:38] And I'm glad he told me that because we were tumbling, and it was such a crazy ride when we hit the atmosphere. [5:43] And I remember thinking, I'm glad Scott told me that, or I would have thought so. [5:47] These guys are in for quite an amazing return to Earth tomorrow, and I'm excited about it. [5:52] It'll be great to hear their stories first person as the whole world's been watching them in that small capsule for the last 10 days. [5:59] Can I follow up on that? [6:00] Just because, you know, there's so much, there are so many things that a normal person just can't understand about what folks like yourself have done. [6:09] And I am very self-aware of that fact. [6:11] But the experience that you're describing with the warning you were given, what is that? [6:17] Like, you feel like you're going to die. [6:18] That seems a little stressful and intense. [6:20] Try and explain that to people. [6:22] So there was a couple things. [6:25] First of all, when the Soyuz comes back, the way the parachutes came out, it felt like the capsule was tumbling for several minutes. [6:32] It tumbled a lot. [6:34] And no one's ever ridden in an Orion capsule. [6:37] So these guys will literally be the first ones to say what it's like to experience that. [6:42] But it was the amount of tumbling and the length of time that I was not—in the space shuttle, it didn't tumble. [6:48] It was kind of a gentle, smooth, you know, one-and-a-half-g reentry. [6:51] The other thing about the Soyuz, when you're in space, you look back at Earth, you can see it moving, but it's so far away. [6:59] Even though you're going—we were going 17,000 miles an hour. [7:03] These guys will be going 25,000. [7:05] It doesn't feel like you're going that fast because it's so far away. [7:09] But as we came back in the Soyuz, we were pretty close to Earth over Africa. [7:14] And I looked out the window, and I finally, for the first time, saw what 17,000 miles an hour looked at. [7:19] So it was a sense of tumbling in the capsule when the drogue parachute started to come out, and also looking out the window and going, man, we are moving really fast. [7:28] I'm not sure if the Orion capsule will be in the right orientation that they'll be able to look out the window. [7:34] But if they do, they're going to see what 25,000 miles an hour looks like, which will be pretty cool. [7:38] The heat—I mean, a lot of people are almost half as hot as the sun. [7:43] Do they feel that? [7:44] Did you feel that? [7:47] So on my first flight, I was a space shuttle pilot, and I—it was like—the shuttle cockpit's like an airliner cockpit. [7:53] So I had some big windows. [7:55] So I actually took my glove off. [7:57] As you're coming back, you see this orange and pink fireball. [8:01] It was basically exploding over the wind. [8:04] It was like being in the club with a strobe light going off inside the cockpit. [8:08] It was nighttime. [8:10] It was very surreal. [8:11] And so I actually put my finger up and felt the window. [8:14] I was curious if I could feel this multi-thousand-degree heat, and I couldn't. [8:17] Now, it's not—there's not just one thin pane of glass. [8:20] There's several panes of glass. [8:22] But I actually took my hand, put it on the window, and I couldn't feel anything. [8:25] So I don't know. [8:26] The capsule might get warm inside. [8:28] We'll see how that is. [8:30] I know the space shuttle did not, and the Soyuz did not. [8:33] So we'll see what their experience is like.