Home » Outer Space » Stars, Galaxies and Universe » Milky Way Galaxy: 200 Billion Stars and Our Solar System

Milky Way Galaxy: 200 Billion Stars and Our Solar System

|
Milky Way Galaxy

“Earth is in the Milky Way galaxy. It’s home to over 200 billion stars with ours being the sun.”


Not only is the Milky Way a huge accumulation of stars, but it holds planets, asteroids, meteors, comets and other solar remnants.

Most stars are at the center of the galaxy with few at the outer edges. A supermassive black hole is at the galactic center.

On the grand scale, the universe holds a mammoth collection of galaxies like the Milky Way. We know this because we observe them using the Hubble Telescope. Galaxies like the Milky Way are rotating around some point in space likely where the Big Bang occurred.

What shape is the Milky Way galaxy?

Milky Way Galaxy

Galaxies are flat because things that rotate flatten out on the rotational access. For example, Earth is longer at the equator axis because of its rotation. Similarly, most galaxies are similar to the shape of a discus.

Based on their visual appearance, Edwin Hubble developed a classification scheme for galaxies. The three classes of galaxies are:

  • Ellipticals
  • Lenticulars
  • Spirals

In a clockwise direction, the entire galaxy is rotating as a barred spiral galaxy. The Milky Way is a flattened disk with spiral arms. This disk contains dust, stars, and gas rotating from a center point.

According to the Hubble Galaxy classification scheme, the Milky Way is an SBc barred spiral galaxy. This means that it’s partway between SBb and SBc.

Who are our neighboring galaxies?

Suns Closest Neighbor

We know the closest neighboring star is Alpha Centauri (Rigil Kentaurus)

ANDROMEDA GALAXY: But the closest galaxy to us is the Andromeda galaxy. This spiral galaxy houses about 1 trillion stars.

So this makes it more than double or even triple the stars compared to the Milky Way.

This galaxy is on a crash course with the Earth due to its gravitational pulls. But no need to panic because this won’t happen for another 4 billion years.

Are there other habitable planets in the Milky Way?

Goldilocks Zone

Lucky for us, Earth is in the Goldilocks zone. This means that it’s within the range where liquid water can persist.

In other words, because Earth receives a hearty portion of the sun’s rays, these conditions are “just right” to sustain water and forms of life. Even here in our Milky Way galaxy, at least 10 habitable planets are within the Goldilocks zone.


“Earth’s Doppelgänger might just be in our neighboring star system Alpha Centauri. This means that only light-years away, there is a glimmer of hope that other life can exist.”


The Milky Way galaxy

Earth is located in the Milky Way galaxy, which has an estimated 200 billion stars. Our sun is one of these many stars and it includes our solar system as well.

Do you want to study the cosmos and beyond? Take a look at some of these online courses offered by universities to help you make your education goals.

If you have any questions or comments about the Milky Way galaxy, please do not hesitate to let us know what’s on your mind. We would love to hear from you!

USM Logo
Become an environmental steward

Professional Certificate in Environmental Management for Sustainability

Enroll in the online program from the UMCES and USMx’s Environmental Management for Sustainability.

2 Comments

  1. Does the 200 – 300 billion stars in the Milky Way account for double and triple systems? E.g. Alpha Centauri with its three stars is accounted as one or as three?

  2. A couple of things:
    1. You classified the MW galaxy as SBc, when the chart says SBb.
    2. The est. size of the MW galaxy ranges from 100 – 200 thousand light-years across. The est. number of stars ranges from 100 – 300 billion.
    3. Proxima Centauri is slightly closer to Earth than Alpha, 4.22 – 4.25 for Proxima; 4.35 for Alpha.
    4. Our doppelganger (?) orbits Proxima, not Alpha, I understand.

Leave a Reply

Your email address will not be published.