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Milky Way
Milky Way Galaxy
Most accurate simulated view of the Milky Way galaxy

The Milky Way galaxy is part of the Local Group, in the Local Sheet, in the Virgo Supercluster, in the Laniakea Supercluster, in the Pisces-Cetus Supercluster Complex.

Milky Way section view

Showing our Sun's location in the Orion (Local) Arm and some of the more notable nebulae in the Sagittarius Arm and Perseus Arm. See detailed Orion Arm views showing Loop Bubbles, Local Bubble, Local Fluff, and more.

Milky Way section view


Milky Way Facts
      1. Type
      2. barred spiral
      1. Age
      2. 13.6 billion years
      1. Mass
      2. 1-1.5 trillion suns
      1. Number of stars
      2. 250-400 billion
      1. Diameter
      2. 170-200,000 light years
      1. Thickness (arms)
      2. 2,000 light years
      1. Bar rotation period
      2. 100-120 million years
      1. Spiral rotation period
      2. 200-360 million years
      1. Escape velocity
      2. 500 km/s
      1. Supermassive black hole
      2. Sagittarius A*

    Milky Way structure

    Galactic Center


    Sagittarius A* Cluster
    Sagittarius A* (supermassive black hole)



    Spiral arms


    Near 3kpc Arm
    Far 3kpc Arm
    Scutum-Centarus Arm
    Sagittarius Arm
    Orion (Local) Arm
    Perseus Arm
    Norma Outer Arm



    Halos


    Fermi Bubbles
    Stellar halo
    Gaseous halo
    Dark matter halo



    Stellar streams


    Monoceros Ring
    Virgo Stream
    Sagittarius Stream
    Magellanic Stream



    Collision objects


    Gaia Sausage
    Smith's Cloud



    Satellite galaxies

    Large Magellanic Cloud, Small Magellanic Cloud, and 50 other dwarf satellite galaxies.