E. Earth and Space Systems · Space

Living and Working in Space

E1.1 A1.3 A1.5About 50 minutes

Learning goals

I can describe the conditions in space that are dangerous for people.
I can explain how these conditions affect the human body and mind.
I can explain how astronauts meet their physical, social and emotional needs in space.
I can design a solution to a problem astronauts face.

Words to know

microgravity
The floating, nearly weightless condition astronauts experience in orbit.

vacuum
A space with almost no air or other matter. Space is nearly a vacuum.

radiation
Energy and tiny particles that travel through space from the Sun and stars. Too much can harm living things.

physiological needs
The body's needs, such as air, water, food, sleep, exercise and staying warm.

isolation
Being cut off from other people or places.

International Space Station (ISS)
A large spacecraft orbiting Earth where astronauts from several countries live and work.

Would you like to live in space?

Imagine six months on the International Space Station. You float everywhere. You see 16 sunrises and 16 sunsets every day, because the station circles Earth about every 90 minutes. You can't go outside without a spacesuit, and you can't visit your family.

People have lived on the station without a break since November 2000. How do they stay healthy and happy?

The station circles Earth about every 90 minutes, so astronauts get 16 sunrises and 16 sunsets in one 24-hour day.

Conditions in space

No air to breathe: space is nearly a vacuum.
Extreme temperatures: in direct sunlight, things get very hot; in shadow, they get extremely cold.
Radiation: without Earth's thick atmosphere and magnetic field to protect them, astronauts receive more radiation.
Microgravity: everything floats, including people, water drops and crumbs.
Isolation and confinement: a small crew lives in a small space, far from family and friends, for months.

The spacecraft and spacesuits protect astronauts from the first three. Microgravity and isolation affect them every day.

Effect on the body or mind	Why it happens	How astronauts meet the need
Bones get weaker	bones no longer carry the body's weight; astronauts lose about 1% of bone density per month (an older adult on Earth loses about 1% per year)	exercise about 2 hours a day, including weight-lifting on a special machine
Muscles get weaker	muscles don't have to work against gravity	treadmill (with a harness pulling them down), stationary bike, resistance machine
Breathing	no air outside	machines supply oxygen and remove carbon dioxide
Drinking	water is heavy and costly to launch	a water recovery system cleans and reuses water
Eating	crumbs and drops float and can get into equipment	packaged foods; tortillas instead of bread; meals shared together
Sleeping	you can't "lie down" without gravity	sleeping bags attached to the wall of a small private cabin
Feeling lonely or stressed	isolation, small space, being far from family	video calls and email with family, crew meals, hobbies like music, a regular schedule, support from teams on the ground

How astronauts stay healthy in space. Bone and exercise facts from the Canadian Space Agency.

Using the numbers in the table: in 6 months an astronaut can lose about 12 times as much bone density as an older adult on Earth. That is why they exercise about 2 hours a day.

Social and emotional needs

Astronauts are people too! Being far away for a long time can be hard. Space agencies help astronauts:

Stay connected: astronauts talk with family by video call and email, and can even phone home.
Be a team: crews train together for a long time before the mission. They eat meals together and celebrate holidays and birthdays.
Have fun: many bring a hobby. Canadian astronaut Chris Hadfield played guitar and recorded music on the station.
Keep a routine: a regular schedule for work, exercise, meals and sleep helps, especially when the Sun rises 16 times a day.
Get support: doctors and psychologists on the ground check in with them.
Look at Earth: many astronauts say looking out the window at Earth helps them feel calm and connected.

Worked example

Let's solve a space problem like an engineer

Problem: astronauts on a long mission are losing bone and muscle strength. Design a solution and explain how it meets their physiological needs.

Understand the problem: in microgravity, bones and muscles don't carry the body's weight, so they weaken. Bone density drops about 1% per month.
Brainstorm: make the muscles and bones work hard anyway, using machines that push or pull against the body.
Choose: a treadmill with a harness that pulls the astronaut down onto the belt, plus a machine that gives resistance, like lifting heavy weights.
Plan the routine: about 2 hours of exercise a day.
Test and improve: doctors measure bone and muscle before, during and after the mission and change the plan if needed.

Daily exercise with a harnessed treadmill and a resistance machine replaces the work gravity does on Earth. This is close to what real astronauts do on the space station.

Just for fun

Why do astronauts pack tortillas instead of bread?

Because floating bread crumbs are a truly crummy problem: they can drift into the equipment! 🌮

Hands-on activity

Design a space habitat feature

You need: paper, pencil, ruler, and recycled materials such as boxes, tape, string and fabric scraps.

Choose a need (A1.3): sleeping, eating, staying clean, exercising, or staying connected with family.
List the problems microgravity and isolation cause for that need. (For example, floating crumbs, or feeling homesick.)
Brainstorm at least three ideas. Choose the best one.
Build a small model or draw a labelled design. For example: a sleeping bag with straps, a crumb-free snack package, a "family wall" for photos and messages, or an exercise strap system.
Test it at home as well as you can. (Can your snack package be opened without spilling? Does your sleeping-bag model stay attached to a wall when you tip it?)
Communicate (A1.5): present your design to your family in 2 minutes. Explain the problem, your solution, and how you would improve it.

What to look for: a strong design clearly matches the problem caused by space conditions, has labels, and was tested and improved. Meeting social and emotional needs (like staying connected) is just as important as physical needs.

Safety: ask before using scissors or knives, and have a grown-up do any cutting of thick cardboard.

Your turn

Name three conditions in space that are dangerous for people.

Why do astronauts' bones get weaker in space?

About how long do astronauts on the space station exercise each day?

How do astronauts get drinking water on the space station?

How do astronauts sleep in space?

Name two ways astronauts stay emotionally healthy.

Why do astronauts see 16 sunrises a day?

More practice: warm-up

Is there air to breathe in space?

What is microgravity?

What do astronauts wear to go outside the station?

Why might bread be a problem in space?

Since when have people lived on the space station without a break?

More practice: on your own

Why does a treadmill on the space station need a harness?

An older adult on Earth loses about 1% of bone density per year. An astronaut loses about 1% per month. How much faster is that?

Why is isolation a problem on a long space mission? Give one solution.

Why do space agencies have crews train together for a long time before a mission?

Why is radiation a bigger danger in space than on Earth's surface?

Challenge

A trip to Mars would take many months each way, and messages to Earth take minutes to arrive. What new problems would this cause for the crew's emotional needs, and how could they be solved?

Explain how the water recovery system meets a physiological need AND solves a practical problem.

Hadfield's guitar served a purpose beyond fun. Explain how music can help meet astronauts' needs.

Check your understanding

Quiz

Which is a condition in space that harms people?

Why do astronauts exercise about 2 hours a day?

About how much bone density do astronauts lose per month without enough exercise?

How do astronauts sleep?

Which helps meet an astronaut's emotional needs?

The space station orbits Earth about every...

For parents and teachers

Big idea (E1.1): analyse the impact of space conditions on humans and explain how astronauts meet their social, emotional and physiological needs. The design activity uses the engineering design process (A1.3) and communication (A1.5).

How to help: the Canadian Space Agency's "Living in space" pages have short videos of astronauts eating, sleeping and exercising. Ask your child how they would feel being away from home for six months and what would help. This connects to their own strategies for coping with stress.

Common difficulties:

Focusing only on physical needs. E1.1 also asks about social and emotional needs.
Thinking astronauts float because there is no gravity. (See the mass and weight lesson.)

Safety: supervise cutting.

Sources: Canadian Space Agency (exercise about 2 hours a day; bone loss about 1% per month vs 1% per year for an older adult; sleeping); NASA Space Station facts (16 orbits a day, about 90 minutes per orbit, crews since November 2000, water recovery).