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By the end of this chapter you'll be able to…

  • 1Describe who Sunita Williams is and her achievements
  • 2Explain how everyday activities change in zero gravity
  • 3Explain why water forms spheres in space
  • 4Describe the International Space Station and its orbit
  • 5Explain the Overview Effect of seeing Earth from space
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Why this chapter matters
'Sunita in Space' follows astronaut Sunita Williams to explore life in zero gravity -- how astronauts eat, drink, sleep, and see Earth from the International Space Station. It sparks curiosity about space, science, and the beauty and fragility of our planet.

Before you start — revise these

A 5-minute refresher here will save you 30 minutes of confusion below.

Sunita in Space — Class 5 EVS (CBSE)

Based on the NCERT Looking Around Grade 5 textbook. Explore space travel through the experience of Sunita Williams, then solve the practice set.


1. Why this chapter matters

What is it like to float in space? How do astronauts eat, sleep, and drink in zero gravity? This chapter follows Sunita Williams' experience in space. Students learn about life without gravity — how things float, how water behaves, and how amazing Earth looks from space. The chapter sparks curiosity about space, science, and the universe.

2. Sunita Williams

Sunita Williams is an American astronaut of Indian origin. She was born in 1965 in Ohio, USA. Her father is from India (Gujarat). She has spent a total of 322 days in space across two missions.

Key achievements

  • Second woman of Indian origin to go to space (after Kalpana Chawla).
  • Set a record for the longest spaceflight by a woman (195 days in 2007).
  • Ran the first marathon in space on the International Space Station (ISS).
  • She has done multiple spacewalks.

3. Zero gravity (weightlessness)

In space, there is very little gravity. Astronauts float — this is called weightlessness or zero gravity.

Effects of zero gravity

ActivityIn zero gravity
WalkingYou float. You push off walls to move around.
EatingFood floats. It is served in pouches or as bite-sized pieces.
DrinkingWater floats in blobs. You drink from a bag with a straw.
SleepingYou sleep in a sleeping bag attached to the wall (so you do not float away).
Brushing teethYou swallow the toothpaste (no spitting — it would float!).
ExercisingYou must exercise 2 hours daily to keep muscles and bones strong.

4. Earth from space

From space, the Earth looks stunning. Sunita Williams described seeing:

  • The blue oceans and white clouds.
  • The brown landmasses and green forests.
  • The thin layer of atmosphere that protects all life.
  • Sunrise and sunset 16 times a day (the ISS orbits Earth every 90 minutes).

Seeing Earth from space gives astronauts a deep appreciation for our planet. This is called the Overview Effect.

5. Water in space

Water behaves very differently in space.

  • Water does not fall — it forms floating balls (spheres) because of surface tension.
  • Astronauts drink water from special bags with straws.
  • Water is recycled on the ISS — even sweat and urine are purified and reused.
  • A water bubble can be used as a magnifying lens.

Why water forms spheres in space

On Earth, gravity pulls water down. In space, there is no gravity to pull it, so surface tension pulls water into the smallest possible shape — a sphere.

6. The International Space Station (ISS)

The ISS is a large spacecraft that orbits Earth. It is a laboratory where astronauts from different countries live and work.

  • Orbits Earth every 90 minutes.
  • Travels at 28,000 km per hour.
  • Has been continuously occupied since November 2000.
  • Countries involved: USA, Russia, Japan, Canada, and European countries.
  • India also has space programmes (ISRO) with missions to the Moon and Mars.

7. Activity corner

Activity 1: Try to eat a meal with your eyes closed while sitting still. Imagine doing this while floating! Write about the experience.

Activity 2: Draw a picture of Earth as seen from space. Colour the oceans blue, the land green/brown, and add white clouds.

Activity 3: Write five questions you would ask an astronaut if you met one.

8. Common mistakes

  • Mistake: Thinking there is no gravity at all in space Fix: There is gravity in space. Astronauts float because they are in free fall — falling towards Earth but moving sideways so fast that they keep missing it.
  • Mistake: Believing astronauts eat 'space food' from tubes like in cartoons Fix: Astronauts eat normal food (like tortillas, fruits, nuts) that is specially packaged.
  • Mistake: Confusing Sunita Williams with Kalpana Chawla Fix: Both are women of Indian origin who went to space. Kalpana Chawla (who died in the Columbia disaster in 2003) was the first Indian woman in space.

9. Key facts

  • Sunita Williams: American astronaut of Indian origin.
  • 322 total days in space across two missions.
  • Zero gravity: astronauts float, food floats, water forms spheres.
  • ISS orbits Earth every 90 minutes at 28,000 km/h.
  • Earth from space: blue oceans, white clouds, thin atmosphere.
  • Water in space: floats as spheres, recycled on the ISS.
  • Astronauts must exercise 2 hours daily in space.

10. Self-test

  1. Who is Sunita Williams?
  2. How do astronauts drink water in space?
  3. What happens to water in zero gravity?
  4. How fast does the International Space Station travel?
  5. What is the 'Overview Effect'?

11. Answer key

  1. Who is Sunita Williams? Answer: She is an American astronaut of Indian origin who has spent over 300 days in space.

  2. How do astronauts drink water in space? Answer: They drink from special bags with straws because water floats in zero gravity.

  3. What happens to water in zero gravity? Answer: Water forms floating spherical blobs due to surface tension.

  4. How fast does the International Space Station travel? Answer: About 28,000 km per hour. It orbits Earth every 90 minutes.

  5. What is the 'Overview Effect'? Answer: The deep appreciation and awe astronauts feel when they see Earth from space — a beautiful, fragile planet with a thin atmosphere.

12. Quick revision

  • Sunita Williams: Indian-origin astronaut, 322 days in space.
  • Zero gravity: floating, special eating and drinking.
  • Water forms spheres in space (surface tension).
  • ISS: travels at 28,000 km/h, orbits in 90 minutes.
  • Earth from space: stunning blue marble.
  • Astronauts exercise, recycle water, and work together.
  • Space travel teaches us to appreciate our planet.
  • India's ISRO has its own successful space programme.

Key formulas & results

Everything you need to memorise, in one card. Screenshot this for revision.

Zero gravity effects
Things float; food and water float; sleep strapped down
Astronauts push off walls to move.
ISS facts
Orbits Earth every 90 minutes at about 28,000 km/h
Astronauts see 16 sunrises and sunsets a day.
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Common mistakes & fixes

These are the exact errors that cost students marks in board exams. Read them once, save yourself the trouble.

WATCH OUT
✗ Thinking there is no gravity at all in space
✓ There is gravity; astronauts float because they are in free fall, moving sideways so fast that they keep missing the Earth.
WATCH OUT
✗ Believing astronauts eat from tubes like in cartoons
✓ They eat fairly normal foods, such as tortillas, fruits, and nuts, that are specially packaged.
WATCH OUT
✗ Confusing Sunita Williams with Kalpana Chawla
✓ Both are women of Indian origin who went to space, but Kalpana Chawla was the first Indian woman in space.

NCERT exercises

Every NCERT exercise from this chapter — what it covers and how many questions to expect.

Think and Imagine
Think and Imagine
Questions on life in zero gravity
4
Questions
Find Out
Find Out
Learning about astronauts and space
4
Questions

Practice problems

Work through this chapter's problems as a readiness check — reveal each solution, mark yourself honestly, and get your gap report at the end.

Readiness check

Are you exam-ready for Sunita in Space?

4 problems from this chapter. Try each one, reveal the worked solution, mark yourself honestly — get your gap report at the end.

4 questions~3 min worth ~5 marks in Tamil Nadu (TNBSE) exams

5-minute revision

The whole chapter, distilled. Read this the night before the exam.

  • •Sunita Williams is an Indian-origin astronaut who spent 322 days in space.
  • •In zero gravity, astronauts and objects float.
  • •Food is packaged and water is sipped from bags with straws.
  • •Water forms floating spheres because of surface tension.
  • •The ISS orbits Earth every 90 minutes at about 28,000 km/h.
  • •Astronauts exercise about two hours daily to stay healthy.
  • •Seeing Earth from space gives the Overview Effect.

Tamil Nadu (TNBSE) marks blueprint

Where the marks come from in this chapter — so you can plan your prep.

Typical chapter weightage: 3-5 marks, depending on the school paper

Question typeMarks eachTypical countWhat it tests
Very Short / MCQ1-21-2Sunita Williams and the ISS
Short Answer2-31Life and water in zero gravity
Prep strategy
  • Remember key facts about Sunita Williams
  • Learn how daily tasks change in zero gravity
  • Explain why water forms spheres
  • Know basic ISS facts

Where this shows up in the real world

This chapter isn't just an exam topic — it lives in the world around you.

Inspiring science

Stories of astronauts inspire children to explore science and space.

Understanding our planet

The view from space shows how precious and fragile Earth is.

Space research

The ISS is a laboratory where experiments help science and medicine.

Exam strategy

Battle-tested tips from teachers and toppers for this chapter.

1
Recall Sunita Williams's key facts
2
Explain floating as free fall, not absence of gravity
3
Use surface tension to explain water spheres
4
Give ISS orbit facts accurately

Going beyond the textbook

For olympiad aspirants and curious learners — topics that build on this chapter.

STRETCH
Find out about India's ISRO missions to the Moon and Mars.
STRETCH
Research how astronauts recycle water on the ISS.

Where else this chapter is tested

CBSE board isn't the only one — other exams test this chapter too.

CBSE Class 5 School ExamHigh
EVS / science OlympiadMedium

Questions students ask

The real ones — pulled from the Q&A community and tutor sessions.

There is actually still gravity in space, even at the height of the International Space Station. Astronauts float because they and the station are in free fall -- constantly falling toward the Earth but also moving sideways so fast that they keep missing it and go around in orbit instead. Since everything falls together, there is no sensation of weight, which is why astronauts and their food and water all float.

On Earth, gravity pulls water downward so it spreads out and flows. In space there is no gravity to pull it, so the water's own surface tension takes over. Surface tension pulls the water into the smallest possible shape, which is a sphere, so water in space floats around as round, wobbling balls that astronauts can even use as a magnifying lens.
Verified by the tuition.in editorial team
Last reviewed on 30 May 2026. Written and reviewed by subject-matter experts — read about our process.
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