The Milky Way Galaxy: Stars, Center & Pictures

Instructor: Jeff Fennell

Jeff has a master's in engineering and has taught Earth science both domestically and internationally.

Our galaxy, the Milky Way, is home to our sun, along with around 250 billion other stars. This lesson will cover the features of our galaxy and provide a quiz at the end to test your knowledge.

The Milky Way is a barred spiral galaxy according to the HCS


The Milky Way is our home. It is also one of 170 billion galaxies in the known universe. Our star, the sun, is one of nearly 250 billion stars within the Milky Way galaxy. The Milky Way appears to have an average size of 100,000 light years across in diameter.

In 1921, Edwin Hubble began to classify the galaxies being observed. From his observations, two distinct types of galaxies were present: spiral and elliptical galaxies. Of the spiral galaxies, two subcategories exist: normal spiral and barred spiral. For almost 80 years, scientists were unsure what type of galaxy the Milky Way was, but advanced observation techniques and computer models show that our galaxy is most likely a barred spiral galaxy.

Older stars make up the galactic bulge


Our galaxy contains about 250 billion stars. After the sun, our next closest star neighbor is Proxima Centauri, which is located 4.242 light years away. This means if you were to travel at the speed of light, it would take 4.242 years to reach our closest neighbor.

Our neighborhood of stars is believed to reside on one of the spiral arms of the Milky Way. The stars on the arms of the spiral of the Milky Way are younger compared to those in the center. Towards the center of the galaxy is a halo of older, dim stars that make up what is known as the galactic bulge.

Galactic bulge of the Milky Way
milky way

Center of the Galaxy

Not too long ago, the centers of galaxies were a mystery. Over the past decade, however, scientists have found evidence that super massive black holes reside at the centers of galaxies. Even our own galaxy has a super massive black hole at the center that we rotate around. It is still unclear what the connection is between galaxies and black holes.

Milky Way
milky way

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