Hi, I’m Jack Hanna. With me is Army, the armadillo.

The armadillo is the only mammal that has bone plates in its skin. The shell is made of plates called shutes.

The number of shutes varies between armadillo species and in some they are flexible enough to allow the animal to curl up and protect itself from predators. The head is also armored and the tail is protected by bony rings.

Penguins are adaptive birds that live in areas from Antarctica to the coast of Africa.

The wings are without quills, and bear only little feathers that one might compare to scales. The wings are shaped like paddles unfit for flight but great for swimming in the ocean. Penguins have tightly packed feathers that overlap to provide waterproofing; and oil from a gland helps to seal their skins from the cold and water.

Just like animals, humans can adapt to extreme environments - like outer space.

In this episode of NASA CONNECT, you’ll learn about the challenges facing the human body in a space environment.

In your classroom, you’ll do a cool hands on activity as you investigate the thermal properties of different materials.

And, using the instructional technology activity, you will gain a solid foundation in the basic principles of the "materials science" discipline through hands-on activities and computer simulations.

So stay tuned as hosts Jennifer Pulley and Dan Geroe take you on another exciting episode of NASA CONNECT!

Hi! Welcome to NASA CONNECT. The show that connects you to math, science, technology and NASA! I’m Dan Geroe!

And I’m Jennifer Pulley!

Welcome to Downtown Houston, Texas! Now, Dan, what is Houston famous for?

Let’s find out!

Houston is famous for a lot of cool stuff but the coolest has to be…

NASA Johnson Space Center!

NASA-Johnson is home to our nation's astronaut corps. The Center is responsible for preparing astronauts for the demands of living and working in space.

Since opening in 1964, Johnson Space Center has managed the design, development, and testing of all United States human spacecraft. The Center specializes in all human spacecraft-related functions including:

life support, power and cooling systems, structures, flight software, robotics, spacesuits and spacewalking equipment.

During the next half-hour, we’ll learn more about how space suits are made…

…what they’re designed to do…

…and what NASA is doing to prepare us for future space flight missions!

But, first, there are a few things you and your teacher need to know.

First, teachers… make sure you have the lesson guide for today’s program. It can be downloaded from our NASA CONNECT web site. In it, you’ll find a great math-based, hands-on activity, and a description of our instructional technology components!

Kids! You’ll want to keep your eyes on Norbert, because, every time he appears with questions, like this, have your cue cards from the lesson guide and your brain ready to answer the questions he gives you.

Oh… and teachers…if you are watching a taped version of this program, every time you see Norbert with a remote, that’s your cue to pause the videotape and discuss the cue card questions.

Have you got all that? Good! Now its time to learn more about spacesuits!

To explore and work in space, human beings must take their environment with them because there is no atmospheric pressure and no oxygen to sustain life.

What is atmospheric pressure?

That’s a good question. Atmospheric pressure is defined as the force exerted by the weight of air molecules. Now, although air molecules are invisible to us they still have weight and take up space. The weight of the Earth’s atmosphere is always pushing down on us.

However, as elevation increases, fewer air molecules are present. Therefore, atmospheric pressure always decreases with increasing altitude.

At 5.5km above sea level, air pressure is only half as dense as it is on the ground. And at 19km feet above sea level, air is so thin that humans must wear pressurized spacesuits.

These pressurized suits supply oxygen for breathing and maintains a near normal atmospheric pressure for the person wearing it.

Now, since space suits are mostly worn by astronauts have you ever wondered what it would be like to wear a spacesuit? You know, just think about how you suit up when you go outside on a cold winter's day.

You have your long pants... shirt.... sweater.. jacket, gloves.. hat.. scarf and boots. You put on quite a bit of clothing to protect yourself from the cold.

Now, imagine what you would have to put on to protect yourself in outer space!

Spacesuits must provide astronauts all the comfort and support that the Earth or a spacecraft does - like atmosphere, water, protection from radiation…

..and going to the bathroom!

If you did not wear a space suit, these are the things that would happen to you…

11. You would become unconscious within 15 seconds because there is no oxygen.
12. Because the atmospheric pressure is so thin, your internal blood pressure would cause your blood to boil and then freeze
13. You would face extreme temperatures: 120 degrees Celsius in the sunlight and minus 100 degrees Celsius in the shade!
14. You would be exposed to various types of radiation from the sun.

And you could be hit by small particles of dust moving at high speed or, even, space debris.

When NASA's Mercury program began, the spacesuits kept the designs of earlier pressurized flight suits used in high altitude aircraft. However, NASA added a material called Mylar which gave the suit strength, and the ability to withstand extreme temperatures.

When Project Gemini came along, Astronauts found it difficult to move in the Mercury spacesuit when it was pressurized; the suit itself was not designed for space walking so some changes had to be made.

Gemini astronauts learned that cooling their suit with air did not work very well.

Often, the astronauts were overheated and exhausted from space walks and their helmets would fog up on the inside from excessive moisture.

Dan Geroe

With the Apollo program, NASA knew that Astronauts would have to walk on the moon. So space suit designers came up with some creative solutions based on information they collected from the Gemini program.

A single spacesuit was developed that had add-ons for moon walking.

Spacesuits used by the Apollo astronauts were no longer air-cooled. A nylon undergarment mesh allowed the astronaut’s body to be cooled with water — similar to way a radiator cools a car’s engine.

Additional layers of fabric allowed for better pressurization and additional heat protection.

For walking on the moon, the spacesuit was supplemented with additional gear —like gloves with rubber fingertips, and a portable life support backpack that contained oxygen, carbon-dioxide removal equipment and cooling water. The spacesuit and backpack weighed 82 kg on Earth, but only 14 kg on the moon due to its lower gravity..

We’ll learn how all of these pieces fit together later in the show.

The materials NASA uses in space have great applications for us here on Earth!

That’s right, Dan. And get this! Many of the advances in space suit technology are also being applied to suits worn by fire fighters?

With new fabrics and a cooling system, new fire suit designs will be able to withstand temperatures up to 261 degrees Celsius compared to a maximum of 149 degrees Celsius for current suits. With better protection, fire fighters will be able to extend the time available to saving lives and property.

Later on in the program, I’ll show you a really cool web site that features a simulation on materials science.

We’ll show you a cool experiment you can do with other students to test the reflective surfaces of different materials under different temperatures.

In the meantime, I’m going to go talk with Phil West, here at Johnson Space Center about how measured spacesuits are sized and fitted for astronauts!

What is an EMU?

Why is sizing a spacesuit critical to astronauts?

Why can't spacesuits be individually tailored for each astronaut?

Hi Jennifer. While early spacesuits were made mostly of soft fabrics, the current spacesuit, which we call, the Extravehicular Mobility Unit or EMU, is made of a combination of hard and soft components to give you protection, flexibility, and comfort.

The suit itself has about 11 layers of material, including an inner cooling garment, pressure garment and thermal micrometeriod garment. All of the layers are sewn, cemented or latched together to form the suit.

So Phil, if I was an astronaut, I would have my own personal spacesuit?

Ah, not quite Jennifer. Each suit is a mini spacecraft costing millions of dollars.

In contrast to early spacesuits, which were individually tailored for each astronaut …

… the EMU has component pieces of varying sizes that can be put together to fit any given astronaut …

Today there are well over 100 astronauts and many of those are trained for spacewalks, but we can only piece together about 14 suits at any one time.

So why is it so important to size spacesuits?

Well Jennifer, just like it’s important to have clothes that aren’t too big or too small for you, an astronaut has to have clothes that fit.

In fact, it’s more important for an astronaut’s suit fits just right. Let’s take your shirt, for example.

When you buy a shirt, you try to get about the right sleeve length, so that you don’t have to roll up your cuff just to work with your hand.

But you don’t buy a shirt based on elbow position or how your elbow bends, right? You buy a shirt based on overall size, collar size or sleeve length.

A spacesuit is more rigid. It may look soft, but when it gets pumped up with oxygen to keep the astronaut alive, even the soft parts get stiff. Then they become more like your shoes.

Everyone knows what happens if your shoes are too big. Your heel comes out or the shoe rubs on your socks or skin — which gets old quick and if the shoes are too small, they become uncomfortable. So think of the spacesuit like your shoes, each part has to fit very well.

Yet we are all different sizes. In shoes, we think about length and width, but what about the rest of the body parts?

Yeah. I mean, what about arm length or leg length or your neck or you head size?

That’s right! Let me show you some things you need to think about!

Where are your shoulders and where is your center of rotation? How far is your knee from your hip? Do you have a long torso or a short torso? What about your fingers? So sizing is critical because the spacesuit becomes a stiff object around you when you pressurize it.

Okay Phil, with all these variables that you have to work with, how do you go about sizing spacesuits?

Well, to size you in a spacesuit, we’d take measurements of different body parts…

… like head circumference, height, vertical trunk diameter, hip and waist, inseam, knee position, elbow position, arm length and even the position of each knuckle.

That data is then processed and compared against available parts in the inventory. Then a fairly accurate estimate is made of what parts are needed to fit the person, from the base of the fiberglass shirt, to the boots, legs and arms.

Aluminum sizing rings are added in key places to adjust lengths. Smaller adjustments can be made through tweaking some other parts.

Technicians assemble a suit from those parts. The astronaut then comes in for a fit check….much like trying on shoes at the store.

You go through a series of motions to see that everything is working right. Then the team tweaks the suit to fit better, and you try again, until you get it right.

If you are a novice, which you probably are if you are just getting fitted for a space suit, you may find you need to ask for more tweaks after you do your first long training session. There may be some problems spots that develop thaty you want to get fixed because they could rub on your skin and cause some pain or discomfort.

Now, gloves are the only place where we’ll build a custom piece of a space suit for a specific person. Even then, we can adjust the length of each finger to fit somebody else of similar size.

So, Phil, how do engineers use math to size spacesuits?

We use statistical averages when designing the range of parts needed to outfit a group of people.

For instance, if you measured all of the heights of all males on Earth it would take next to forever. But if you take a sample of all the males and measure their heights, you will arrive at a set of numbers that will actually represent the total number of males on Earth.

A typical male ranges in height from approximately 170 to 190 cm or 67 to 75 inches.

We also represent this range using percentiles - the 5^th percentile to the 95^th percentile male. 95^th percentile means that 95% of the males are shorter than 190 cm and 5% are taller. I’d guess that most NBA basketball players are above the 95^th percentile, therefore we couldn’t fit them in a spacesuit. This would cost too much. The 5^th percentile would then mean that 5% of the males are shorter than 170 cm and 95% are taller.

Hey Phil, what about the female astronauts?

Well, the technique is the same, the numbers are just a little bit smaller because female astronauts are typically smaller than male astronauts. You know Jennifer, one of the most challenging things about measuring for a spacesuit is measuring the human body.

It’s easy to measure a room just wall-to-wall but to find the same point on a body consistently is difficult. So accuracy is very important in sizing a spacesuit.

You know, Phil, speaking of spacesuits, I see that we have two here.

We do. This bright orange space suit is the advanced escape crew suit and that’s what the astronauts wear for shuttle launches and landings.

In fact, I think this one is about your size. So why don’t you try it on?

Oh, Phil that’d be awesome!!

Hey! Check me out! I’m dressed for space! You know, this space suit fits pretty well but I think it needs a few adjustments. So while we do that, let’s go visit Dan. He is going to show you a cool web site that features a thermal conductivity simulation - —that’s insulation to you and me! Let’s go see what he’s doing!

1. Welcome to my domain. This show’s instructional technology activities were provided by NASA’s Classroom of the Future located in Wheeling, West Virginia.
2. Knowing how conductive a material is, helps us determine if it is suitable for space vehicle and spacesuit design. That’s also true down here on Earth, especially for such things as our homes, clothing, and shoes.
3. Go to Dan’s Domain from the NASA CONNECT web site then select the "Dressed for Space" program. Here’s where you’ll find links to the activity, Career Zone, resources, and a math tutorial provided by Riverdeep Interactive Learning, one of our program partners.
4. In this show’s web-based activity, you’ll select different types of materials like wood, carbon foam, and stainless steel to test how well they work for insulation purposes.
5. You’ll be able to adjust the thickness of the materials,
6. and you’ll be able to change the amount of power applied to the heating coil in the house.
7. The actual temperature inside the house is dependent on the power applied to the heater and the total insulating capacity of the house.
8. We also have another classroom activity tied to the web site. There’s a low-tech version and a high-tech version.

In classrooms without laboratory sensors, you’ll use stopwatches and pushpins inserted into the bottom of quartered, cold butter pats pressed onto four objects (a metal knife, a plastic knife, a glass rod, and a wooden chopstick). These are placed into a beaker of 85-90 degree C water. As heat is conducted up the material, the butter softens and the pushpin begins to droop downward and may eventually fall off.

10. You’ll use the time it takes for each pushpin to droop as a measure of heat conductance. You can also touch the top of each material to feel how hot it is.

11. In the high tech version of the experiment, you’ll tape temperature probes attached to a calculator-based lab data collection apparatus to each of the four materials to obtain temperature readings at 2, 4, and 6 minutes. At the end of 6 minutes, the ou’ll subtract the 2-minute temperature from the 6-minute temperature to see which material conducted the most heat. The most conductive material will have the greatest increase in temperature and vice versa.
12. That’s it for my domain. Special thanks to the students at Arapaho Middle school in Arapaho, Wyoming for helping us demonstrate part of this show’s Web-based activity.

Okay. Let’s review. On today’s show, we’ve learned about the spacesuits from the Mercury, the Gemini, and the Apollo Space programs.

We also learned about the current spacesuit, the EMU, and how sampling and statistical averaging are used in sizing spacesuits.

And we learned how space suit technology is being applied right here on Earth to solve problems.

But what is NASA doing to design, manufacture, and test the next generation of spacesuit? Amy Ross here at NASA Johnson Space Center has the scoop.

What will the future spacesuit be used for?

How do you evaluate advanced spacesuits?

Analyzing the data, which suit has the best elbow performance?

Hello Jennifer.

Hey Amy. How are you doing?

Fine, thanks. Part of my job as a spacesuit engineer is to evaluate the performance characteristics of advanced space suit configurations. The suits shuttle astronauts wear for space walking are good for fixing an occasional satellite, and will be adequate for assembling the International Space Station. But they were not designed for mountaineering or searching for water on Mars.

That is why NASA is working to develop the early prototype of what will become, in decades to come, a versatile outfit for exploring the nearby planets.

Three configurations that we are currently testing are the H-Suit, the I-Suit, and the D-suit.

The H-Suit, is a hybrid space suit configuration made up of hard components and soft components. The hard components include the hard upper torso and the lower torso brief assembly. Soft components include the fabric elbows and fabric knees. Another important feature of the H-Suit is that it incorporates rotating bearings at the multi-axis joints.

Amy, what are rotating bearings and multi-axis joints?

Multi-axis joints is a mobility system that allows a person to move through most of their natural ranges of motion. . Rotating bearings placed at major joints in the body help provide that mobility.

The H-Suit has bearings at the shoulder, upper arm, waist, upper hip, mid-hip, upper leg, and ankle joints. We call the H-Suit a rear-entry suit because the suit is entered through a hatch on the backside of the hard upper torso. This suit weighs approximately 59kgs or 130 pounds.

Another advanced spacesuit that we are evaluating is the I-suit.

The I-suit is primarily a soft suit, yet it incorporates a limited number of bearings at the shoulder, upper arm, upper hip and upper leg. This gives astronauts the ability to rotate their shoulders, arms, and legs. This suit is light, packs smaller, and potentially will be less expensive to make and to tailor to individual astronauts. The result is a suit that weighs 29kgs or 64 pounds.

When it comes to exploring the surface of other planets, astronauts will be hiking a great deal. To give the astronauts the best footwear, commercial boot makers provided us with some insight into a boot that would fit on the spacesuit. The boot of the I-Suit has special air bladders that can be inflated to provide a snug fit. Also, the suit has a body seal closure and mounting points for backpack integration.

Ok Amy you mentioned the H-suit, the I-suit and a third suit…..the D-Suit?

That’s right Jennifer. The D-Suit is a lightweight "soft" suit that weighs about 12kgs or 26 pounds.

The D-suit has bearings at the upper arm. While the soft suit is much lighter than the H-Suit and the I-suit with their many bearings, it affords an astronaut less movement especially in the lower torso. The spacesuit of the future will combine the positive traits of all three suits. The idea is we would take the best out of what we learned from these prototypes and incorporate that into the requirements for the next prototype that we build.

Okay Amy, how do you evaluate each suit to see which one is the best?

Recently, we evaluated each suit based on several categories like sizing, comfort, weight, packing volume, and isolated joint range of motion.

For the category of isolated joint range of motion, we broke it down into thirteen different types of motion.

For example, we looked at ankle, knee, hip, waist, shoulder and elbow flexion and extension. In other words, how well do these body parts flex and extend when astronauts are in the spacesuits.

Now, does this process involve any math?

We wouldn’t be able to evaluate the prototypes without using math.

We looked at the elbow flexion and extension for the H-Suit, I-Suit, and D-Suit. For this particular study, we used three test subjects, two males and one female. In order to compare the three prototypes, we needed a baseline.

How did you develop the baseline?

To develop the baseline, we use the "full range of motion, measured in degrees, that astronauts make wearing only the Liquid Cooling and Ventilation Garment, or LCVG". The LCVG is the liquid cooled underwear that is worn under all spacesuits.

Next, we measure and record the full range of motion, in degrees, for an astronaut wearing each of the three prototype suits. Finally, we compare the measurements recorded for any one prototype to the measurements recorded for the LCVG, which is our baseline measurement. The difference between the number of degrees in the baseline measurement and the number of degrees in the prototype measurement…

…is how we compare the suits.

Okay, so what does this chart tell us?

This chart shows us the range of motion for each test subject wearing the LCVG and the three prototype spacesuits.

Let’s take test subject AR wearing the H-Suit. The value, 135, means that the test subject has a range of motion of 135 degrees from extension to flexsion. Comparing this value to the baseline, which is 143 degrees, we see the test subject wearing the H-Suit lost mobility by 8 degrees.

So, Amy, by looking at the data, on the average, the test subjects had the best range of motion with the I-Suit and the worse range of motion with the D-Suit.

That’s right Jennifer, but also notice that the difference in the range of motion for the three prototypes is only 6 degrees….which is not a lot.

However, for comfort, the test subjects preferred the H-Suit elbow over the I-Suit and D-Suit. Two test subjects reported that the I-Suit and D-suit arm bit into their biceps causing some discomfort. So, for the combination of comfort and range of motion, the H-Suit elbow exhibited overall superior performance.

Results from this test and many others will help guide the design, manufacture, and implementation of the advanced spacesuit of the future.

That’s great! Thank you so much Amy! Okay, now that we’ve learned about the design and manufacture of materials to help humans live in outer space it’s time for you to become a NASA Researcher. The Rice School right here in Houston, Texas has an awesome hands-on activity they want to show you!

Hi! We’re from The Rice School here in Houston, Texas.

Hola! Estamos estudiantes de The Rice School aqui en Houston, Texas.

NASA CONNECT has asked us to show you this program’s Hands On Activity!

La NASA Conecta ha pedido que le mostremos las actividades manos de esta semana.

Here are the main objectives!

Aqui estan los objectivos principales!

• you’ll investigate how different colors and materials absorb and reflect heat.
• You’ll predict which materials have optimum thermal properties
• You’ll measure and record temperature
• You will plot, analyze and summarize data
• You will design and test improvements to the activity
• And, you will use problem solving strategies in a real-world application.

The list of materials you’ll need for this activity can be downloaded from the NASA Connect Web Site.

"Good morning class. Today, your job is to investigate the thermal properties of various materials and colors, graph and analyze results and to develop your own combination of materials to be considered for future spacesuits."

Teachers will distribute all materials while…

…students organize into 6 groups. Within each group, students will be given designated roles as data recorder, thermometer reader and data analyzer.

Using the temperature data card, each group will record their Group Number, Materials used, and the Experimental Process of heating or cooling to be analyzed

Students will cut out cardboard lids to fit the cans by tracing the circumference of the can.

A small puncture should be made in the center of the lid to hold the thermometer. This hole needs to be small so that it can hold the thermometer firmly in place.

Attach the lid to each can using clear tape.

Different groups will cover their cans with different materials like white or black construction paper, aluminum foil, cotton balls, foam meat trays or insulated tape.

Once the can is completely covered, insert the thermometer into the cardboard hole at the top, being careful not to touch the side of the can.

Now, you’re ready to conduct your test!

First, measure and record the temperature of the room. Be sure you do this in degrees Celsius!

First, conduct the heat test!

Place each set of cans an equal distance from a heat lamp or place them outside in the full sun.

After one minute has expired, record the value on the thermometer onto the temperature data card. Repeat this process for twelve additional readings.

Now its time for the cold test!

Using a large garbage bag, line the inside of the cardboard box then fill the box with enough ice to reach the top of the cans.

Insert the thermometer into the top of the can and repeat the collection of data as you did in the heat test.

Again, record your results on the temperature data card.

Once all information has been collected, graph your data onto a grid using different colored pencils as outlined in the Lesson Guide.

"Okay, in your individual findings, what materials do you think could improve on your thermal results? Claire?

The metal can with the black construction paper!

What inferences can you make about color, materials and temperature variations? Roxanne?

The darker the color, the greater the temperature variation!

Special thanks to the AIAA Chapter at The University of Houston for helping us with this activity.

Thanks! We had a great experience! And, we encourage teachers to visit our web site to learn more about the AIAA Mentorship program in your area!

Well, that wraps up another episode of NASA CONNECT!

We’d like to thank everyone who helped make this program possible!

Got a comment, question or suggestion? Email them to

connect@larc.nasa.gov.

Or pick up a pen and mail them to

NASA CONNECT

NASA's Center for Distance Learning

NASA Langley Research Center

Mail Stop 400

Hampton, VA 23681

Teachers! If you would like a video tape of this program and the accompanying lesson guide, check out the NASA CONNECT web site.

So, until next time, stay connected to Math, Science, Technology, and NASA!

See you then! Adios! Goodbye from Houston!