What Is a Galaxy?

Galaxies are concentrations of stars, gas, dust, and dark matter. They come in a variety of shapes and sizes. Some are fated to collide, like the Milky Way and Andromeda. Credits Video: NASA, ESA, CSA, Joseph Olmsted (STScI)

Topics

  • nebula
  • cosmology
  • Andromeda
  • dark matter
  • gravity
  • spiral galaxies
  • elliptical galaxies
  • irregular galaxies
  • supermassive black hole
  • galaxy interactions
  • Andromeda Galaxy
  • Henrietta Swan Leavitt
  • Edwin Hubble
  • Milky Way
  • galaxies
  • astronomy
  • cosmic interactions
  • galaxy types