Welcome To My School Study
Practice Class 8 Science MCQ Questions with Answers based on the latest NCERT syllabus. Learn about the phases of the Moon, stars, Orion constellation, planets of the Solar System, and the Red Planet with original concept-based explanations, exam-focused notes, and NCERT-aligned content for CBSE and State Board students.
Do You Know
Chapter Information
Subject: Science
Class: 8
Chapter: Some Natural Phenomena / Stars and the Solar System
Question Type: Multiple Choice Questions (MCQs)
Difficulty Level: Easy to Moderate
Based On: Latest NCERT Syllabus
Introduction
The night sky is filled with fascinating celestial objects such as the Moon, stars, planets, and constellations. Understanding why the Moon changes its appearance, identifying constellations like Orion, and learning about the Solar System helps students develop a scientific understanding of astronomy. This practice set provides original, NCERT-aligned explanations to strengthen concepts and improve exam preparation.
What You Will Learn
✔ Phases of the Moon
✔ Nearest stars to Earth
✔ Orion constellation
✔ Planets of the Solar System
✔ The Red Planet (Mars)
Why This Topic Is Important?
Astronomy is an important part of Class 8 Science and helps students understand Earth’s place in the universe. Questions from this chapter are frequently asked in CBSE, State Board, Olympiad, and scholarship examinations.
Exam Relevance
These questions are useful for:
✔ CBSE Exams
✔ State Board Exams
✔ School Tests
✔ Unit Tests
✔ Half-Yearly Exams
✔ Annual Exams
✔ Olympiad Preparation
✔ Scholarship Examinations
Q1. Which is the nearest star to the Earth after the Sun?
A) Orion
B) Sirius
C) Pole Star
D) Alpha Centauri
Answer: Alpha Centauri
Concept
The Sun is the nearest star to Earth. The next nearest star system is Alpha Centauri.
Explanation
Alpha Centauri is the nearest known star system beyond the Sun. Although it is extremely far from Earth, it is closer than other bright stars such as Sirius and the Pole Star.
The Sun is the closest star to the Earth and provides us with heat and light. After the Sun, the nearest star system to Earth is Alpha Centauri. It is located about 4.37 light-years away from Earth.
What is Alpha Centauri?
Alpha Centauri is not a single star. It is actually a group of stars known as a star system. It mainly contains:
- Alpha Centauri A
- Alpha Centauri B
- Proxima Centauri
Among these, Proxima Centauri is the closest individual star to Earth.
Distance Measurement in Space
Distances in space are extremely large, so scientists use a special unit called a light-year.
What is a Light-Year?
A light-year is the distance traveled by light in one year.
Light travels at about:
300,000 kilometers per second.
Importance of Alpha Centauri
Scientists study Alpha Centauri because:
- It is very close compared to other stars
- It may contain planets
- It helps us understand the universe better
Difference Between Stars and Planets
Stars
- Produce their own light and heat
- Example: Sun, Sirius
Planets
- Do not produce their own light
- Revolve around stars
- Example: Earth, Mars
Interesting Facts
- The Sun is also a star.
- Alpha Centauri can sometimes be seen from the Southern Hemisphere.
- Space scientists continue researching nearby star systems for future space missions.
Exam Focus
Remember:
- Nearest star to Earth → Sun
- Next nearest star system → Alpha Centauri
Q2. Which planet is also known as the ‘Red Planet’?
A) Mars
B) Venus
C) Jupiter
D) Saturn
Answer: Mars
Concept
Planets are often identified by their unique physical characteristics.
Explanation
Mars is called the Red Planet because its surface contains iron oxide (rust), giving it a reddish appearance when viewed from Earth.
Mars is called the “Red Planet” because its surface appears reddish in color. The red appearance is due to iron oxide, commonly known as rust, present on its surface.
Position of Mars in the Solar System
Mars is the fourth planet from the Sun:
- Mercury
- Venus
- Earth
- Mars
Why Mars Appears Red
The soil and rocks on Mars contain large amounts of iron minerals. Over time, these minerals reacted with oxygen and formed rust-like compounds, giving Mars its red color.
Features of Mars
- Thin atmosphere
- Cold climate
- Dust storms
- Mountains and valleys
- Polar ice caps
Moons of Mars
Mars has two small moons:
- Phobos
- Deimos
Importance of Mars
Scientists are very interested in Mars because:
- It may have supported life in the past
- Water ice exists there
- Future human missions may visit Mars
Space Missions to Mars
Many countries have sent spacecraft and rovers to study Mars.
Famous Mars Missions
- NASA’s Perseverance Rover
- Curiosity Rover
- India’s Mangalyaan Mission
Comparison Between Earth and Mars
Earth
- Suitable for life
- Has liquid water
- Oxygen-rich atmosphere
Mars
- Very cold
- Thin atmosphere
- No confirmed life yet
Interesting Facts About Mars
- A day on Mars is almost equal to a day on Earth.
- Mars has the largest volcano in the solar system called Olympus Mons.
- Scientists believe Mars once had flowing water.
Exam Focus
Remember: Mars = Red Planet
Q3. The phases of the Moon occur because:
A) Moon changes its shape.
B) Clouds block the view.
C) Earth covers the Moon.
D) We see only that part of the Moon which reflects light towards us.
Answer: We see only that part of the Moon which reflects light towards us.
Concept
The Moon does not produce its own light. It reflects sunlight.
Explanation
The Moon revolves around the Earth, and the portion illuminated by the Sun changes its position relative to us. Therefore, we see different illuminated portions of the Moon at different times, giving rise to the phases of the Moon. The Moon itself does not change its shape.
The Moon does not produce its own light. It shines because it reflects sunlight. Different shapes of the Moon seen from Earth are called phases of the Moon.
Why Do Moon Phases Occur?
The phases occur because:
- The Moon revolves around the Earth
- Sunlight falls on the Moon
- We can see only the illuminated part facing Earth
The Moon itself does not change shape.
Main Phases of the Moon
New Moon
Moon is not visible from Earth.
Crescent Moon
A small curved part becomes visible.
First Quarter
Half of the Moon appears illuminated.
Gibbous Moon
More than half becomes visible.
Full Moon
Entire illuminated side faces Earth.
Last Quarter
Again, only half becomes visible.
Time Taken for Moon Phases
The Moon takes about 29.5 days to complete one cycle of phases.
Importance of Moon Phases
Moon phases are important for:
- Calendars
- Tides in oceans
- Astronomy studies
- Cultural and religious events
Difference Between Moon Phases and Eclipse
Moon Phases
Occur because of changing positions of Earth, Moon, and Sun.
Eclipse
Occurs when one celestial body blocks another.
Interesting Facts
- The Moon is Earth’s natural satellite.
- The same side of the Moon always faces Earth.
- Ancient people used Moon phases to measure time.
Exam Focus
Remember: Moon phases occur because we observe different sunlit portions of the Moon.
Q4. Which of the following is not a planet of the Sun?
A) Sirius
B) Earth
C) Saturn
D) Mercury
Answer: Sirius
Concept
The Solar System contains the Sun, planets, moons, and other celestial bodies.
Explanation
Sirius is a star, not a planet. Earth, Mercury, and Saturn are all planets that revolve around the Sun.
Sirius is not a planet. It is actually a star and is one of the brightest stars visible in the night sky.
What is Sirius?
Sirius belongs to the constellation Canis Major and is often called the “Dog Star.”
Why Sirius is Not a Planet
Planets revolve around the Sun and do not produce their own light. Sirius produces its own light and energy because it is a star.
Planets of the Solar System
The planets of the solar system are:
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
Characteristics of Stars
- Extremely hot
- Produce light and heat
- Made mostly of gases
- Very far from Earth
Characteristics of Planets
- Revolve around stars
- Reflect light
- Smaller than stars
Importance of Studying Stars
Scientists study stars to understand:
- Formation of galaxies
- Space evolution
- Universe structure
Interesting Facts About Sirius
- Sirius is brighter than most stars visible from Earth.
- It is nearly twice as massive as the Sun.
- Ancient civilizations used Sirius for navigation and calendars.
Exam Focus
Remember: Sirius is the brightest star visible in the night sky, not a planet.
Q5. Orion is a:
A) Star
B) Galaxy
C) Planet
D) Constellation
Answer: Constellation
Concept
A constellation is a recognizable pattern formed by a group of stars.
Explanation
Orion is one of the most well-known constellations visible in the night sky. It consists of several bright stars that appear to form the shape of a hunter.
Orion is one of the most famous constellations visible in the night sky. A constellation is a group of stars forming a recognizable pattern.
What is a Constellation?
Constellations help astronomers identify regions of the sky. Ancient people imagined shapes and stories by connecting stars together.
Features of Orion
Orion is often called “The Hunter” because its stars form a pattern that looks like a hunter holding a weapon.
Important Stars in Orion
Betelgeuse
A large red supergiant star.
Rigel
A very bright blue-white star.
Orion’s Belt
Three bright stars aligned in a straight line.
Visibility of Orion
Orion can be seen clearly during winter in many parts of the world.
Importance of Constellations
Constellations help in:
- Navigation
- Astronomy studies
- Locating stars and planets
- Understanding the sky
Orion in History
Different cultures created stories about Orion and used constellations for navigation and seasonal prediction.
Difference Between Galaxy and Constellation
Galaxy
A huge system containing billions of stars.
Constellation
A pattern formed by stars seen from Earth.
Interesting Facts About Orion
- Orion is one of the easiest constellations to recognize.
- Orion Nebula is located within this constellation.
- Many stars in Orion are much larger than the Sun.
Exam Focus
Remember: Orion is a constellation, not a single star or planet.
Important Concepts
1. Phases of the Moon
- The Moon reflects sunlight.
- Different illuminated portions are visible from Earth at different times.
- The Moon does not change its actual shape.
2. Stars
- Stars produce their own light and heat.
- The Sun is a star.
- Alpha Centauri is the nearest known star system after the Sun.
3. Constellation
Definition:
A constellation is a group of stars that forms a recognizable pattern in the sky.
Example:
- Orion
- Ursa Major
- Cassiopeia
4. Solar System
The eight planets in order are:
- Mercury
- Venus
- Earth
- Mars
- Jupiter
- Saturn
- Uranus
- Neptune
5. Mars
Characteristics:
- Fourth planet from the Sun.
- Known as the Red Planet.
- Has two natural satellites: Phobos and Deimos.
Related Practice Questions
- Why does the Moon appear to change its shape?
- Name the nearest star to Earth.
- What is a constellation? Give two examples.
- Which objects are included in the Solar System?
- Why is Mars called the Red Planet?
Mini Quiz Challenge
True or False
- The Moon produces its own light.
- Alpha Centauri is the nearest known star system after the Sun.
- Orion is a constellation.
- Sirius is a planet.
- Mars is known as the Red Planet.
Exam Tips
✔ Do not confuse the phases of the Moon with a lunar eclipse.
✔ Remember that Orion is a constellation, not a star.
✔ Learn the order of the planets in the Solar System.
✔ Revise important stars and constellations mentioned in NCERT.
✔ Differentiate between stars and planets.
Quick Revision Notes
✔ The Moon reflects sunlight.
✔ Moon phases occur because different illuminated portions are visible.
✔ Alpha Centauri is the nearest known star system after the Sun.
✔ Orion is a constellation.
✔ Sirius is a star.
✔ Mars is called the Red Planet.
Common Mistakes Students Make
❌ Thinking the Moon changes its actual shape.
❌ Confusing Sirius with a planet.
❌ Assuming Orion is a single star.
❌ Forgetting that stars produce their own light.
❌ Mixing up Mars and Venus.
Key Takeaways
- The phases of the Moon are caused by the changing visible sunlit portion of the Moon.
- Alpha Centauri is the nearest known star system after the Sun.
- Orion is a famous constellation.
- Sirius is a star and not a planet.
- Mars is known as the Red Planet because of its reddish surface.
FAQs
1. Why do we see different phases of the Moon?
We see different phases because different portions of the Moon illuminated by the Sun become visible from Earth as the Moon revolves around our planet.
2. Which is the nearest star to Earth?
The Sun is the nearest star to Earth. After the Sun, the nearest known star system is Alpha Centauri.
3. What is Orion?
Orion is a constellation, which is a group of stars forming a recognizable pattern in the night sky.
4. Is Sirius a planet?
No. Sirius is a star, not a planet.
5. Why is Mars called the Red Planet?
Mars appears reddish because its surface contains iron oxide (rust), which gives it a red colour.
NCERT Reference
Book: NCERT Science Class 8
Chapter: Chapter 17 – Stars and the Solar System
Based On: Latest NCERT Curriculum (CBSE)
Related links
- Class 8 Social Science Chapter 1 How, When and Where
- Class 8 Science Chapter 1 Crop Production and Management
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-13
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-12
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-11
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-9
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-8
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-7
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-6
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-5
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-4
- Class 8 Maths Chapter 3 Understanding Quadrilaterals part-3
- Class 8 Maths Chapter 2 Linear Equations in One Variable part-11
Latest Posts
- Class 9 Maths Chapter 5 Introduction to Euclid’s Geometry
- Class 10 Maths Chapter 5 -Arithmetic Progressions
- Class 7 Maths Chapter 5 – Parallel and Intersecting Lines
- Class 8 Maths Chapter 5 – Number Play
- Class 9 English Chapter 2 The Pot Maker
Join Our Other Communities
Instagram , Youtube , Facebook
