Study Guide: The Sun

Key Facts

• The sun is a star located at the center of the solar system.
• It is a massive sphere of hot plasma.
• The sun's energy is produced by nuclear fusion reactions.
• The sun's gravitational pull keeps the planets in orbit around it.

Structure of the Sun

• Core: The central region where nuclear fusion occurs, producing energy.
• Radiative Zone: Energy from the core moves outward through this layer.
• Convective Zone: Hot plasma rises and cools, creating convection currents.
• Photosphere: The visible surface of the sun.
• Chromosphere: The layer above the photosphere, where solar flares and prominences occur.
• Corona: The outermost layer of the sun's atmosphere.

Importance of the Sun

• Provides energy for photosynthesis in plants.
• Influences climate and weather patterns on Earth.
• Maintains the orbits of the planets in the solar system.

Interesting Facts

• The sun is about 4.6 billion years old and is roughly halfway through its life cycle.
• Its diameter is about 109 times that of Earth.
• The sun's mass accounts for about 99.86% of the total mass of the solar system.

Fun Activity

To understand the concept of solar energy, try using a magnifying glass to focus sunlight onto a piece of paper and observe how it creates heat. This demonstrates the concentration of solar energy and its potential for practical use.