Structure of the Sun

Overview of the Sun's Structure

  • Core

    • Composition: 10% of the Sun's mass; primarily hydrogen and helium.
    • Process: Fusion of hydrogen into helium, releasing energy.
    • State of Matter: Plasma (liquid gaseous mixture).
    • Temperature: 15,000,000 °K (27,000,000 °F).
    • Density: 160 tons per cubic meter.

  • Radiative Zone

    • Location: Surrounds the core.
    • Function: Insulates the core and allows heat to escape slowly (approximately 1 million years to transfer heat to the next zone).

  • Convective Zone

    • Location: Just outside the radiative zone.
    • Temperature: Cooler than the radiative zone.
    • Density: Less dense compared to inner zones.
    • Process: Convection, where hot plasma rises and cooler plasma sinks, effectively bringing heat to the sun's surface.

Outer Layers of the Sun

  • Photosphere

    • The visible surface of the Sun.

  • Chromosphere

    • A layer above the photosphere, observable during solar eclipses.

  • Corona

    • The outer atmosphere of the Sun, extending millions of kilometers into space.

Solar Phenomena

  • Solar Flares

    • Sudden eruptions of energy on the surface of the Sun.

  • Prominences

    • Large, bright features extending outward from the Sun's surface, often in the form of arches.

  • Coronal Mass Ejections (CMEs)

    • Massive bursts of solar wind and magnetic fields rising above the solar corona.

  • Sunspots

    • Temporary phenomena on the photosphere that appear as spots darker than the surrounding areas.

  • Coronal Holes

    • Areas on the solar corona with low density, allowing solar wind to escape more easily.

Composition of the Sun

  • Hydrogen: Approximately 92% of the Sun's composition.
  • Helium: Roughly 8% of the Sun's composition.
  • Note: The composition has remained relatively stable since formation, with ongoing fusion changing hydrogen to helium.