Description

The Sun is the star at the center of our solar system. It’s a nearly perfect sphere composed primarily of hydrogen and helium, with traces of other elements. The Sun’s influence extends far beyond Pluto, influencing the orbits of planets and smaller bodies in the solar system.

Composition
Hydrogen: ~73%
Helium: ~25%
Other elements (oxygen, carbon, neon, and iron): ~2%
Main Features
Core: This is where nuclear fusion occurs, converting hydrogen into helium and producing an enormous amount of energy.
Radiative Zone: Energy produced in the core moves outward through this zone via radiation.
Convective Zone: In this outermost layer of the Sun’s interior, energy is transported towards the surface via convection currents.
Photosphere: This is the visible surface of the Sun that we see from Earth. Its temperature is about 5,500 degrees Celsius.
Chromosphere: Located above the photosphere, this thin layer becomes visible during total solar eclipses as a reddish rim.
Corona: The Sun’s outer atmosphere, visible during a total solar eclipse. It extends millions of kilometers into space.

Notably, the Sun also produces a solar wind, a stream of charged particles that flow outwards from the Sun’s upper atmosphere.

Importance to Life on Earth

The Sun plays a crucial role in supporting life on earth. It provides light and heat, driving weather patterns and enabling photosynthesis in plants, which in turn produce oxygen – a critical component for most life forms on Earth.

Studying the Sun

Scientists use various methods to study the Sun, including observatories on Earth, satellites, and even spacecraft. For instance, NASA’s Parker Solar Probe was launched in 2018 to directly explore the Sun’s corona.

Other Suns

In astronomical terms, any celestial body that can conduct nuclear fusion of hydrogen in its core, much like our Sun, is classified as a “star” or “sun.” There are billions of such stars in our galaxy alone, each one unique in its size, brightness, lifespan, and composition.

Note: Although “Sun” refers specifically to the star at the center of our own solar system, it is sometimes used colloquially to refer to any star that might have its own orbiting planets.