A star is a luminous spheroid of plasma held together by self-gravity. [1] The nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night; their immense distances from Earth …

Apr 29, 2026 · What is a star? 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 …

Mar 11, 2026 · A star’s gas provides its fuel, and its mass determines how rapidly it runs through its supply, with lower-mass stars burning longer, dimmer, and cooler than very massive stars.

Nov 13, 2025 · Learn how stars form from collapsing gas clouds and evolve through stages like the main sequence, red giant, and supernova in this guide to stellar evolution.

May 8, 2025 · How does a star work? How do they form, live, and eventually die? Learn more about these distant objects and their major importance in the universe.

Sep 21, 2024 · As a star approaches the end of its lifespan, it no longer has hydrogen to transform into helium in its core. Unable to complete the nuclear fusion process, the star begins to succumb to …

6 days ago · Capella, Alpha Aurigae (α Aur), is a quadruple star system composed of two pairs of binary stars located 41.929 light-years away in the northern constellation Auriga…

Though stars may appear static, they rotate and vary in luminosity. There are hundreds of billions of stars in the Milky Way Galaxy alone. Among them is our Sun, the closest star to Earth.

Sep 26, 2022 · How are stars named? And what happens when they die? These star facts explain the science of the night sky.

The apparent brightness of a star is measured by its apparent magnitude, which is the brightness of a star with respect to the star’s luminosity, distance from Earth, and the altering of the star’s light as it …