stjörnurnar

Stjörnurnar is the Icelandic word for stars. In astronomy, stars are massive, luminous spheres of plasma held together by their own gravity. The Sun, our own star, is an example of a typical star. Stars are born from vast clouds of gas and dust called nebulae. Within these nebulae, gravity causes denser regions to collapse, forming protostars. As a protostar accumulates mass, its core temperature and pressure increase until nuclear fusion begins. This process, where lighter atomic nuclei combine to form heavier ones, releases immense amounts of energy, causing the star to shine.

The life cycle of a star depends primarily on its mass. Smaller stars, like red dwarfs, burn their fuel slowly and can live for trillions of years. More massive stars burn brighter and hotter, but have much shorter lifespans, typically millions or billions of years. When stars exhaust their nuclear fuel, they undergo significant changes. Lower-mass stars may eventually become white dwarfs, which are dense, hot remnants that slowly cool over time. Massive stars can end their lives in spectacular supernova explosions, leaving behind either neutron stars or black holes. Stars are fundamental components of galaxies, and their collective light forms the starlit sky visible from Earth.