01 / THE ENGINE
Fusion at the center
Hydrogen fuses into helium in the core, releasing energy that eventually escapes as sunlight.
← Solar SystemOur star.
SOLAR SYSTEM / THE SUN
Our star.
Everything begins with light.
A world of plasma, powered by fusion. Meet the star at the heart of our solar system.
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DRAG TO ROTATE
ARTISTIC MODEL · TEXTURE & ROTATION NOT TO SCALEDIAMETER~1.4 million km
CORE TEMPERATURE~15 million °C
AGE~4.6 billion years
02 / THE LAYERS
From core to corona
Energy travels through the radiative and convection zones. Above them lie the photosphere, chromosphere and corona.
03 / SPACE WEATHER
A restless star
Magnetic activity produces sunspots, flares and eruptions. Some eruptions can affect Earth’s space environment.
LOOK A LITTLE CLOSER
Small facts. Big discoveries.
No solid ground
The visible “surface” is a layer of hot plasma called the photosphere.
An unexpected temperature
The corona is much hotter than the visible surface.
Different speeds
The equator rotates in about 25 Earth days; the poles take about 36.