R
Rishtaara
Science · Class 8

Stars and the Solar System

Moon phases, constellations, and structure of the solar system.

4 sections15–25 min read6 MCQs · 2 examples

Chapter Overview

The solar system has the Sun, eight planets, dwarf planets, asteroids, and comets. This chapter covers constellations, phases of Moon, eclipses, and artificial satellites.

Solar System

  • Planets orbit Sun; order: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune
  • Inner rocky planets; outer gas giants
  • Pluto reclassified dwarf planet

Moon and Eclipses

  • Moon phases: new moon → waxing → full → waning (29.5 days)
  • Solar eclipse: Moon blocks Sun (day becomes dark)
  • Lunar eclipse: Earth blocks Sun's light to Moon

Stars and Constellations

  • Stars emit own light; planets reflect sunlight
  • Constellations: Ursa Major (Saptarishi), Orion, Cassiopeia
  • Pole Star (Dhruv) near north celestial pole

Solved Examples

Step-by-step solutions — read each step before checking the final answer.

Moon phases

Why do we see different Moon shapes?

  1. 1Moon orbits Earth — we see lit portion
  2. 2Sunlight illuminates half of Moon always
  3. 3Angle changes daily

Answer

Changing angle of sunlit half

Solar eclipse

When does solar eclipse occur?

  1. 1New moon — Moon between Earth and Sun
  2. 2Moon's shadow on Earth
  3. 3Never look directly at Sun

Answer

New moon phase; Moon blocks Sun

Key Points to Remember

  • ISRO launches artificial satellites (Aryabhata, Chandrayaan)
  • Light-year is distance not time
  • Comets have tail pointing away from Sun

Exam Tips

  • Draw solar system with planet order
  • Explain phases of Moon
  • Distinguish solar and lunar eclipse

Practice MCQs — Stars and the Solar System

Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.

Question 1 of 6Score: 0/0

Planets revolve around: