science facts

Galaxies are vast systems of stars, gas, dust, and dark matter bound together by gravity. Our galaxy, the Milky Way, contains over 100 billion stars. Galaxies come in different shapes—spiral, elliptical, and irregular. They can merge and interact, triggering new star formation. Most galaxies have a supermassive black hole at their center. The universe holds over 2 trillion galaxies, each millions to trillions of light-years apart, constantly moving and evolving due to cosmic expansion.