Stars are giant balls of hot gas – mostly hydrogen, with some helium and small amounts of other elements. Every star has its own life cycle, ranging from a few million to trillions of years, and its properties change as it ages.
Many other stars are visible to the naked eye at night; their immense distances from Earth make them appear as fixed points of light. The most prominent stars have been categorised into constellations and asterisms, and many of the brightest stars have proper names.
A star is any massive self-luminous celestial body of gas that shines by radiation derived from its internal energy sources. Of the tens of billions of trillions of stars in the observable universe, only a very small percentage are visible to the naked eye. Why do stars twinkle?
Stars are luminous spheres made of plasma – a superheated gas threaded with a magnetic field. They are made mostly of hydrogen, which stars fuse in their cores. That process releases energy, which pushes against the weight of the outer layers of the star and keeps it stable.
Stars are massive, luminous spheres of gas, mainly composed of hydrogen, with smaller amounts of helium and other elements. The lifespan of a star varies widely, generally ranging from several million to several trillion years.
How are stars named? And what happens when they die? These star facts explain the science of the night sky.
What are stars, how do they form and die? Our guide packed with facts about stars and answers to some of the most commonly-asked questions.
Stars are spherical balls of hot, ionized gas (plasma) held together by their own gravity. Stars are the most fundamental building blocks of our universe.