Stars are enormous balls of hot gas that produce their own light and energy. They are among the most important objects in the universe.
According to NASA, stars shine because of a process called nuclear fusion, where hydrogen atoms combine to form helium and release huge amounts of energy. This energy travels through space as light and heat.
The Sun is the closest star to Earth and the center of our Solar System. It provides the light and warmth needed for life on our planet.
Like other stars, the Sun is made mostly of hydrogen and helium gases.
Stars begin their lives in large clouds of gas and dust called nebulae.
Gravity pulls the gas and dust together until the center becomes hot enough for nuclear fusion to start.
When fusion begins, a new star is born.
The life of a star depends on its size:
Stars are grouped together in galaxies.
Our Solar System is located in the Milky Way Galaxy, which contains billions of stars.
Galaxies come in different shapes, including spiral, elliptical, and irregular galaxies.
Stars vary in size, color, and temperature:
Stars create many of the elements found in the universe.
They help scientists understand the age, structure, and evolution of galaxies.
Without stars, planets and life as we know it would not exist.
Stars are giant glowing spheres of hot gas that light up the universe. They are born in nebulae, produce energy through nuclear fusion, and go through different stages during their lives.
The Sun, our nearest star, is just one of the billions of stars in the Milky Way Galaxy.
By studying stars, NASA learns more about the history and future of the universe.
Source: NASA Science - Stars