Spiral Galaxies
Characterized by a central bulge surrounded by a flat, rotating disk of stars. Their striking spiral arms are regions of active star formation.
What is a Galaxy?
A galaxy is a sprawling space system composed of dust, gas, and countless stars, all held together by gravity. Our own planet Earth is located within a spiral galaxy known as the Milky Way, just one of billions of galaxies in the observable universe.
Classifications of Galaxies
Elliptical Galaxies
Ranging from nearly spherical to elongated shapes, these galaxies contain older stars and very little gas and dust, meaning new star formation is rare.
Irregular Galaxies
Lacking a distinct shape, these chaotic structures are often the result of gravitational interactions or collisions with other galaxies.
The Milky Way
Our cosmic neighborhood. It measures about 100,000 light-years across and contains roughly 100 to 400 billion stars. At its core lies Sagittarius A*, a supermassive black hole.