Our Star-The Sun main content.

Our Star-The Sun

Part of Hall of the Universe.

A circular exhibit table in the Cullman Hall of the Universe that features information about the Sun. AMNH/D. Finnin

Our Sun is an ordinary star, just one among hundreds of billions of stars in the Milky Way Galaxy. As the only star we can observe in detail, it provides a basis for our understanding of all stars. The Sun is composed almost entirely of hydrogen and helium gas. Multimillion-degree temperatures in its dense core sustain nuclear fusion, providing the energy source for sunlight. The surface of the Sun is marked by colossal magnetic storms. The Sun’s gravity holds in orbit a family of planets, moons, asteroids, and comets - the solar system.

Sun Wavelengths

These images are observations of the Sun in many wavelengths of light. Seething activity and tremendous outbursts are everyday occurrences.

Sunspots

The Sun usually displays a few dark splotches. These sunspots are regions of concentrated magnetic fields. They are slightly cooler than their surroundings, and so appear dark only by contrast.

Solar Flares and Eruptions

Small areas on the Sun’s surface can suddenly heat to millions of degrees and erupt. Such explosions release x-rays and spew vast clouds of energetic subatomic particles out into space.