Milky Way

The Milky Way Key words black hole galactic center galactic plane galaxy globular cluster

Local Arm Milky Way spiral galaxy supermassive black hole

Components of the Milky Way 1 2 3 4

A dense bulging center with a high concentration of stars. A surrounding halo of stars. Trailing arms with less concentration of stars. Our Sun, about 30,000 ly from the center.

The Milky Way Milky Way is visible as an irregular band of faint light across the night sky. ● This band is the arm of our galaxy in which the Sun is located. ● Astronomers refer to our galaxy as a whole as the Milky Way.

2,000 light years

● The

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100,000 light years

Our galaxy ● Our

galaxy is a spiral galaxy with four major arms. ● It is thought to be unusually large. ● It contains about 100 billion stars. ● The central bulge is densely populated with old red stars. ● The arms are mostly populated by young blue stars. ● A spherical halo of old dull stars surrounds the main disc. ● Clusters of old stars (between 10,000 and a million) known as globular clusters also surround the main disc. ● Some astronomers believe there may be a supermassive black hole at the galactic center.

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The Sun’s place ● The

Sun is situated in one of the Milky Way’s spiral arms known as the Orion or Local Arm. ● It is about 28,000 light years from the galactic center and about 20 light years above the center of the galactic plane.

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