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CIE iGCSE Co-ordinated Sciences-P6.1 The Solar System- Study Notes- New Syllabus

CIE iGCSE Co-ordinated Sciences-P6.1 The Solar System – Study Notes

CIE iGCSE Co-ordinated Sciences-P6.1 The Solar System – Study Notes -CIE iGCSE Co-ordinated Sciences – per latest Syllabus.

Key Concepts:

Core

1. Describe the Solar System as containing:
(a) one star, the Sun
(b) the eight named planets and know their order from the Sun
(c) minor planets that orbit the Sun, including dwarf planets such as Pluto and asteroids in the asteroid belt
(d) moons, that orbit the planets

CIE iGCSE Co-Ordinated Sciences-Concise Summary Notes- All Topics

The Solar System

(a) The Sun:

    • The Solar System contains one star – the Sun.
    • The Sun is a medium-sized yellow star (G-type main-sequence).
    • Contains about 99.9% of the total mass of the Solar System.
    • Source of light and heat for all planets.
    • Provides the gravitational force that keeps planets and other bodies in orbit.
  •  

(b) The Eight Planets (in order from the Sun):

  • Mercury – smallest planet, closest to the Sun, no atmosphere.
  • Venus – thick carbon dioxide atmosphere, hottest planet.
  • Earth – only known planet with life, water in all three states.
  • Mars – the “Red Planet”, thin atmosphere, polar ice caps.
  • Jupiter – largest planet, gas giant, Great Red Spot storm.
  • Saturn – gas giant, famous for its ring system.
  • Uranus – ice giant, tilted axis (rotates on its side).
  • Neptune – farthest planet, strong winds, ice giant.

Mnemonic:My Very Educated Mother Just Served Us Noodles

(c) Minor Planets and Other Bodies:

    • Dwarf Planets: e.g., Pluto, Eris, Ceres – smaller bodies orbiting the Sun.
    • Asteroids: Rocky objects, mostly found in the asteroid belt between Mars and Jupiter.
    • Comets: Made of ice and rock; develop tails when near the Sun due to sublimation of ice.
    • Meteoroids: Small rocky fragments that can enter Earth’s atmosphere as meteors.

(d) Moons (Natural Satellites):

    • Moons orbit planets due to gravity.
    • Earth’s Moon stabilises Earth’s tilt and causes tides.
    • Jupiter has at least 79 moons (largest: Ganymede, Io, Europa, Callisto).
    • Saturn has over 80 moons (including Titan, larger than Mercury).
    • Moons vary in size from tiny asteroid-like rocks to planet-sized bodies.

Example

Which planet is the farthest from the Sun, and what are two of its key features?

▶️Answer/Explanation

Step (1): The farthest planet from the Sun is Neptune.

Step (2): Key features include:

  • It is an ice giant with a thick atmosphere of hydrogen, helium, and methane.
  • It has the strongest winds in the Solar System (up to 2000 km/h).

Final Answer: Neptune – farthest planet, ice giant with extreme winds.

Example 

Write down the eight planets of the Solar System in order, starting from the Sun.

▶️Answer/Explanation

Step (1): Recall the order using the mnemonic “My Very Educated Mother Just Served Us Noodles.”

Step (2): Planets in order:

Final Answer: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

Example 

Pluto is no longer classified as a major planet. State its current classification and one reason for this change.

▶️Answer/Explanation

Step (1): Pluto was reclassified in 2006 by the International Astronomical Union (IAU).

Step (2): Its current classification is a dwarf planet.

Step (3): Reason: Pluto does not clear its orbit of other debris, one of the conditions required to be called a planet.

Final Answer: Pluto is a dwarf planet because it shares its orbit with other objects in the Kuiper Belt.

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