The Solar System

The Sun

Our star: a ball of hot gas so big that 109 Earths would fit across it. Never look at it without a proper solar filter.

The Sun in ultraviolet
Our star seen by NASA’s Solar Dynamics Observatory, showing hot, magnetically active regions. Never look at the Sun without a proper filter. Credit: NASA/GSFC/Solar Dynamics Observatory, Public domain (NASA).
Size
1,392,700 km across. About 109 times as wide as Earth.
One orbit
About 230 million years to circle the Milky Way
One day
About 25 days at its equator
Family
Eight planets, five named dwarf planets and countless comets
Spacecraft
Parker Solar Probe flies through its outer atmosphere; SOHO and the Solar Dynamics Observatory watch it every day.

Sizes and periods from NASA’s planetary fact sheets; moon counts from NASA Science.