astronomy – How do stars evolve over time?

Stellar Evolution: The Physics of Cosmic Lifecycles Stars are not fixed beacons of light. They are high-pressure engines engaged in a constant tug-of-war between the inward crush of gravity and the outward push of nuclear fusion. To track how a star evolves, you must look at its birth mass as a predetermined destiny. Think of … Read more

astronomy – What is dark matter and how do we know it exists?

The Evidence for Dark Matter: Moving Beyond Theory Dark matter accounts for approximately 27% of the total mass-energy content of the universe, while ordinary matter—stars, planets, and gas—makes up less than 5%. We know this not through direct observation, but through precise gravitational measurements. Think of dark matter as the invisible scaffolding of a skyscraper; … Read more