Chasing Life

'Hey there, welcome to Paging Dr. Gupta. Thank you so much for joining us. This has become a real community. People calling in, writing in. I love hearing from you. I love your health questions. So this week, we're gonna do a special Artemis II edition of the show. Think of it as a helmet tip to the four pioneering crew members. They returned to Earth April 10th, last week, after a 10-day mission to the far side of the moon and back. Now, you might know. I'm a huge fan of space; I'm huge fan the science behind keeping humans healthy as they journey beyond our planet. And apparently judging from all the questions you've been sending in, many of you are as well. So let's blast off, let's not delay. Ok Kyra is back with us, what's our first question?

'You know, Sanjay, I too am a bit of a space enthusiast, and the whole time watching the Artemis II mission live-streamed, I was just so curious, you know, from a health perspective, what is NASA most concerned about when it comes to the crew?

'Well, this is a great question, and the short answer is RIDGE. R-I-D-G-E. I'm going to tell you what that stands for after this short break.

All right, welcome back to Paging Dr. Gupta. Today, we are answering questions about the Artemis II mission. It's amazing how many people are interested in this. First up, what types of health issues is NASA most worried about?

Well, it's NASA, so of course, they have an acronym for what they're worried about. And the acronym is RIDGE: radiation, isolation, distance from Earth, gravity, and environment. Let me tell you something, they get very granular about all these various topics. So if you think about all of these buckets of potential concerns, we can start to address a few of them.

So gravity, for example. The minimal gravity conditions. There's lots of things that happen. Your muscle mass, your bone mass, those can both be affected. Those can both be diminished pretty quickly in a microgravity environment. The fluid in your lower body, that starts to migrate toward the head. That can leave the faces of the astronauts looking kind of puffy. If you look at images of those astronauts in space, they often look different than those same astronauts do back on Earth. That's because of that fluid migration.

But to get even more specific, as that fluid migrates, all sorts of other things happen. For example, people may develop headaches as a result of the congestion. Their eyes may start to change shape. So, when they look at the bright moon, for example... And then look back inside the capsule, things may be hard to acclimate. Their taste buds may change. We learned that from one of the NASA doctors. It's part of the reason that NASA sends up five different types of hot sauces up to the capsule as well.

'Now, one thing I will tell you is that the members of the crew, they do complete daily exercises. They're testing it out on a brand new Artemis flywheel. It's an exercise contraption that's about the size of a carry-on suitcase. They can do aerobic resistive and rowing exercises, bicep curls, bent over rows, deadlifts, squats, calf raises. Again, this can help with the muscle mass, the bone density, and also to help recalibrate the fluids in the body.

NASA is also trying to answer some very specific health questions. So every day when the astronauts wake up before they brush their teeth or they exercise, they take a saliva test. This is essentially filter paper, which they put on their tongue The saliva absorbs into it, then they fold it up, put it in their pockets, and bring it home. When they get home, NASA can look at those pieces of paper and they can find hormone levels and biomarkers looking for changes in immunity. They can even see whether or not viral DNA has been reactivated. This is kind of a fascinating issue. There's a theory that in a microgravity environment, viral DNA, perhaps from a previous viral infection, can actually be reactivated, potentially causing infection and potentially spreading. And again potentially spreading to other astronauts whose own immunity may be impacted by the microgravity environment.

It's fascinating. It's NASA. They get really detailed about these kinds of things. And by the way, they've actually seen viral DNA reactivation on the International Space Station so NASA is now interested in seeing what happens with Artemis as they go further further into deep space.

Another thing they're studying is the R from RIDGE: radiation. You know, radiation is emitted from the sun, then there's also cosmic radiation from the galaxy. The question is, what are the effects on the brain, the cardiovascular system, the immune function we were just talking about, cancer, bone marrow? So what they're doing is they're putting radiation sensors throughout the crew module and each of the crew members, also wearing a dosimeter in their pocket. This is now the first time they're being used beyond Earth's orbit. They're hoping that the data can warn the crew if perhaps they need to build a shelter to protect from radiation caused by space weather events made by the sun, such as a solar flare.

'Another thing being looked at is the impact that deep space travel has on the mind. I just want you to picture this for a second. The Orion spacecraft module that the four crew members of the Artemis 2 mission are traveling in has habitable space about the size of a studio apartment. It's much smaller than the International Space Station. That is basically a six-bedroom house with six sleeping quarters, two bathrooms, and a gym. These four astronauts are sleeping, eating, exercising, and everything else in very tight quarters. And the reason this is important is because future deep space flight missions are very likely to occur in crafts of this size as well. So another study is monitoring how the crew functions, lives, and works in a very confined space.

'The astronauts wear these trackers that are monitoring their movement and their sleep in real time. What NASA will do is combine this information with cognitive and team dynamic data to understand how close quarters, really close quarters, affect health, safety, and performance. And this will give a glimpse into when the mission is longer and even further away. For example, communication. It takes about 3 to 14 seconds, one way, to communicate from Earth to the Moon. When you do Earth to Mars, it's 44 minutes round-trip. So understanding how astronauts handle that sort of isolation will be very, very important.

So many questions about Artemis II, we'll try and get to more of them right after this break.

Alright, welcome back to Paging Dr. Gupta. Who do we have next?

'Yeah so next up we actually have a few questions about sleep. So a grandma in Canada wrote in on behalf of her seven-year-old grandson Cammie asking about astronauts' schedules and whether they're actually able to feel rested during a mission. And then we also had Malachi from Florida who was wondering what sleep even looks like in space especially when you're floating the whole time.

'All right, I love that seven-year-old Cammie's grandmother writing in. First of all, Cammie, you're right: We all need to be well-rested so we can perform at our peak. I will tell you, astronauts commonly experience sleep deprivation during space flight. Noise, temperature, vibration, light— we know all those things can inhibit sleep, and a lot of those things are amplified when you're up in space. Also, circadian disturbances are present. The day-night cycle, that can be all jumbled up. These aspects can lead to fatigue and can lead to errors while performing tasks. So this is very important. NASA wants these astronauts to maintain a high level of cognition during every phase of the mission, so they gotta catch shut-eye -- that's a really important part of the mission.

'But they weren't just floating around. They slept in sleeping bags attached to the wall of the Orion, and all four crew members slept at the same time. Early in the mission we know sleep was broken up into shorter chunks due to mission-critical events that the astronauts had to handle. But once the spacecraft was on a stable trajectory, the crew transitioned to a regular sleep schedule of about eight hour blocks.

NASA is very interested in how the crew sleeps in deep space and they're doing a study: so the crew members had these wristband devices that record their sleep and their movements very closely. You gotta believe that the crew probably feels a little bit like Cammie: NASA's telling them when to go to bed and when to wake up.

Alright, what other questions do we have about deep space?

So our next question is coming from Brenda in New Jersey, and she's wondering, since water is so heavy, how do astronauts actually get enough of it up there, and how do they properly stay hydrated over the course of the mission?

'As Brenda knows, water is obviously essential. NASA knows it too, here's what the agency says specifically: Being well hydrated during operations is absolutely critical as dehydration can result in decrements in decision-making, concentration, and physiology of the crew.

And I can tell you that even a small amount of dehydration, just a couple of percent, can actually lead to a measurable decrease in cognitive function. So NASA rocketed the water up to space with the astronauts and everything else. There are four water tanks, each containing about 125 pounds of water. Each tank then is connected to two water lines that lead to a potable water dispenser in the crew module. And it's not just for drinking. Sometimes that water is used to rehydrate the food as well. So a lot of food goes up dry and then gets hydrated up in space with this same water.

Okay, I think we have time for one more question.

All right, Sanjay, last up, we've got a bit of a spicy one. Nosa from Texas wants you to explain about the hot sauce to help the astronauts taste.

Yes, this has become a very, very popular topic of discussion. According to NASA, there are five different hot sauces flying around the moon with the crew. It's kind of incredible. Out of all the things you send to space, hot sauce ends up being a really important one. Why? Turns out microgravity can diminish the astronauts' ability to taste. Part of it is a direct impact on taste buds. Another part of it is probably significant congestion in the sinuses and the nose, which impedes the ability to smell. And we know a large part of taste is actually your ability to smell. So fluids in the body get affected by reduced gravity conditions as we've already talked about. And because of the impact on taste buds and your overall sinuses, the astronauts tend to crave a little bit more spicy foods in space.

'I will tell you the Artemis crew did a food test in 2023 where they got to try various foods and then pick the ones that they took with them on their mission. NASA produces heat-stabilized food in pouches, similar to something known as MREs, meals ready to eat, which are often used by the military. These are specially designed to support the nutritional needs of astronauts in space. Most common food items include tortillas. They started off with 58 tortillas on the spacecraft. Also wheat flatbread, vegetable quiche, breakfast sausage, couscous with nuts. And again, some foods, where you probably want a little hot sauce.

It's fascinating, I love everything about space and there's so much to learn from a health perspective and there are so many things to do to keep these astronauts safe.

'That's all the time we have for today's special Artemis II edition of Paging Dr. Gupta. Thanks to everyone who sent in the questions. Please keep them coming because your voice is what brings this show to life. If there's something health related you've been wondering about, send it to us. We might answer it next week. Record a voice memo and email it to pagingdrgupta at cnn.com. That's paging D-R gupta.com or give us a call 470-396-0832 and leave a message.