Difference between Galaxy and Universe
When the discussion of ‘how the world came to be’ arises, including our solar system and beyond, we ponder our evolution and why we evolved so differently from the myriad of plants and animals on Earth. Some of us look up to the stars and ask poignant questions that have yet to be definitively answered. What is our place in the ‘galaxy’ and in the ‘universe’? What are these heavenly bodies and are there others out there who look like us? Are the same principles true in our galaxy supported in other galaxies and universes? The terms have been casually interchanged so often that people now seem to have a hard time differentiating between them. Are these two terms really one and the same? Read on.
Definition
A galaxy is great system of stars, asteroids, gas, dust and dark matter, all held together by a central star which exerts an immense gravitational pull. Galaxies can have trillions of stars called giants, or may have tens of million stars and are therefore called dwarfs. These stars orbit around the mass at the center. There are many galaxies in outer space.
The word “universe” is composed of all forms of matter around us. It is the earth, sky, energy and everything we can perceive. Cosmologists have clarified the term to mean the space beyond ours and the space-as-we-know-it. There are theories that state that there are other universes that we don’t know of that other universes are not visible to our eyes or instruments and can be considered to be in separate dimensions. According to scientists, these universes beyond ours are detached completely from our own and even though interdimensional or even mulitdimensional travel is hinted at in science fiction TV, movies and books, it is not a known phenomenon. Speculation of life outside of the planet Earth is fueled by those who purport that there may be or are beings who can travel interdimensionally.
Similar Terms
The term “galaxy”, having come from the greek word for “milky” is also commonly called “Milky Way galaxy” because it is basically a cluster of stars, gas and dust and unidentified matter that flows into a pattern that looks milky from our point of view when looking towards to center of it. A galaxy is also often termed “star cluster” or “star system”.
Some people erringly use these terms to refer to “the Solar System” of which the Sun is the center pulling planets into an orderly orbit.
The word universe comes from the Old French word Univers, which then came from the Latin universum, believed to mean “everything combined into one”. The word can be compared to words like “world”, “nature” or “cosmos” because it basically is represented by everything around us, including gases and energy. The everyday word “everything” has also been associated with the word universe.
Composition
Galaxies are believed to be composed of stars, star fragments, gas, dust, dark matter, and a center force known as a black hole. A single galaxy could comprise several star clusters and different interstellar clouds.
The universe, on the other hand, is composed of the earth and everything we see around it and the outer space including all observable galaxies. The solar system is but part of our universe. The universe is believed to contain constantly evolving matter. It is composed of atoms, molecules, energies, and gases that all make up this entire cosmos.
Summary
- Galaxy refers to clusters to starry matter and gases. Universe refers to space and matter as we know it and includes all observable galaxies.
- Galaxy’s synonyms are star clusters and Milky Way. Universe’s synonyms are world, cosmos and everything.
- Galaxy is composed of stars, gases, dust and dark matter. Universe comprises all forms of matter around us and in space.
