A star is a celestial body that produces its own light through nuclear reactions occurring in its core. The Sun is the closest and most familiar example, but there are billions of other stars in our galaxy, each with its own physical characteristics and evolutionary history.
The closest star to us, Proxima Centauri, is a small red dwarf located about 4 light-years away, which is nearly 250,000 times farther than the Sun. Other remarkable stars populate our sky, such as Sirius, a binary system composed of Sirius A and Sirius B, or Betelgeuse, a massive red supergiant with a radius about 900 times that of the Sun.
Observing stars means exploring a diversity of sizes, colors, temperatures, and evolutionary stages. Some are young and massive, while others are old and nearing the end of their lives. Studying them helps us understand the formation of galaxies, the evolution of matter, and the fundamental mechanisms that shape the universe. Each star tells part of the cosmic story.
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Carbon Stars: Dying Stars that Sow the Seeds of Life 
Magnetars: When a Neutron Star Becomes a Magnetic Bomb 
The Immortals of the Cosmos: When the Universe Goes Dark, They Will Still Shine 
Antikythera Mechanism: The Gears of the Cosmos 
The Stars, Legacy of a Golden Age: Arabic Astronomy 
Stars: Cosmic Forges of Chemical Elements 
Adaptive Optics and Laser Guide Stars 
Habitable Zones: The Sweet Spot for Living Near Stars 
Pulsar: A Beating Stellar Heart 
Giants of the Milky Way: Top of the Most Massive, Largest, and Brightest Stars 
The First Minerals of Stellar Systems 
What is a Collapsar? 
The life of the stars: From the collapse of the nebula to the cataclysmic explosion 
When a Star Dies: Birth of a Black Hole 
Neutron Stars: When Atoms No Longer Exist 
Blue Giant Stars and Red Supergiants: The Fate of Massive Stars 
Gravitational Collapse: Formation and Birth of Stars 
The mystery of gamma-ray bursts 
White Dwarfs: Stars at the End of Their Life 
Brown Dwarfs: Between Stars and Giant Planets 
The Wind of Stars: Interaction between Light and Cosmic Dust 
The Brightest Stars in the Sky: Top 50 
The Cigar Explosion 
Escape velocity of small objects from black holes 
Gould's belt, a stellar firework 
The Death of Stars: How Their Mass Decides Their Final Fate 
Blue, white, yellow, orange stars 
The Pleiades: The Seven Sisters and Hundreds of Stars 
The Star Fomalhaut: The Mouth of the Fish 
Yellow Dwarfs: The Sun and Its Stellar Cousins 
Star Clusters: Jewels of the Deep Sky 
What is a Cepheid? 
Turn off the stars to see exoplanets 
Betelgeuse: Giant Star on the Edge of Chaos in Orion 
Bright Planets, Twinkling Stars: The Art of Recognizing Them 
From the Naked Eye to the Space Telescope: What Methods Evaluate the Distance of Stars? 
U Camelopardalis: The Carbon Star Losing Its Envelope 
Red Dwarfs: The Smallest Stars 
V838 Monocerotis: The Star That Lit Up Like a Supernova Without Collapsing 
Stars near Alpha Centauri 
Super explosion and supernova SN 1572 
Coatlicue, the star at the origin of our Sun