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Course: American Museum of Natural History > Unit 2
Lesson 3: GalaxiesFormation and Evolution of Galaxies
In the early universe, there were no galaxies. Today, there are many billions. How did they form? Astronomers use the fundamental laws of physics to deduce the basic story of galaxy formation. Galaxies form out of immense clouds of gas that collapse and rotate. As they evolve, stars form within them. Entire galaxies can collide, changing their appearance. Looking deep into space, we see galaxies at earlier stages in their lives, and learn more about their evolution. They are more numerous, display unusual shapes, and have episodes of energetic outbursts. Galaxies can be seen back to more than 10 billion years ago.
Processes in Galaxy Formation
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- What is the average size of a galaxy?(6 votes)
- The Milky Way is 100,000 to 120,000 light years across.(1 vote)
- Where do the spirals come from? And what causes the waves to glow?(6 votes)
- question if the gravity stopped working even in space to what would happen?Where would all the planets go?(3 votes)
- If gravity stopped working, there would be two possible outcomes. Firstly, if the galaxy's gravity stopped working, and nothing else did, then all the star systems that make up the galaxy would fly away in a perfectly straight line, carrying anything orbiting with them. However, if all gravity suddenly turned off, galaxies, star systems, nebulae, everything, would fall apart, and the universe would become a giant element soup.(1 vote)
- are there exoplanets in other galaxies?(3 votes)
- Yes, all galaxies are made up primarily of stars, may of which have exoplanets orbiting them.(1 vote)
- How old is the Milky Way, and how many rotations has it made until now?(4 votes)
- A few thousand years old - just look at the genealogy in the Bible.(0 votes)
- how do they explode(2 votes)
- Does gravity play a role in the formation of galaxies?(1 vote)
- Yes, gravity is the reason galaxies form, and is what keeps them together in the first place.(1 vote)
- why does the first one look like someone zoomed in on veins in the human eye😆(0 votes)