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Course: Middle school Earth and space science - NGSS > Unit 1
Lesson 2: Galaxies and gravityGalaxies and gravity
Review your understanding of galaxies and gravity in this free article aligned to NGSS standards.
Key points:
- A galaxy is a huge collection of gas, dust, and stars. Earth and its solar system are part of a galaxy called the Milky Way.
- Most galaxies are organized into galaxy groups or clusters. The Milky Way is part of a group of galaxies called the Local Group.
- All of these systems are held together by a force called gravity. Gravity is an attractive, or pulling, force that exists between all objects in the universe.
- The force of gravity between two objects depends on their masses and the distance between them. The greater the masses and the shorter the distance, the stronger the force of gravity.
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What will happen if you get suck in a milky way.(27 votes)
We are in the Milky Way.(128 votes)
What will happen when the galaxies collide?(25 votes)
Because there is so much space between the stars in galaxies, it’s not very likely that any one star (or our solar system) would be significantly messed up from this happening. The galaxies would effectively pass through each other (imagine ghosts going through each other) while deforming a bit. Then the galaxies would gravitationally attract each other again and keep going back and forth a few times until they merged to form a new, bigger galaxy. You can actually look up pictures of spiral galaxies in various stages of merging to get an idea of what this might look like.
Does that help?(67 votes)
How Big Is Sagittarius A*?(16 votes)- Its radius is about 13.67 million miles, 46 million km, or 100 AU. Its mass is around 4 million times the mass of our sun.(28 votes)
What will happen when the Andromeda Galaxy and our Milky Way Galaxy collide? Will our galaxy survive the collision?(14 votes)
how were the planits made(12 votes)
Our solar system formed 4.6 billion years ago from a solar nebula, which is a cloud of gas and dust. A nearby supernova explosion caused a shock wave, which likely led to the collapse of the solar nebula. The Sun formed in the center with the planets in orbit around it. Moons also formed in orbit around several of the gas giants.(21 votes)
If we didn't have Gravity and it rain would the rain stay up in air ?(11 votes)
we would probably be floating and i dont think the rain would even come down(19 votes)
- Are gallixes rotading a blakholl(8 votes)
yes it is rotading a blakholl(9 votes)
hello there i want friend(8 votes)
What are some other galaxies in our local group other than the milky way and andromeda?(5 votes)- The three big ones in our local group are the Milky Way, Andromeda, and Triangulum. There are many dwarf galaxies there, too, including: Tucana Dwarf, Phoenix Dwarf, Cetus Dwarf, and NGC 3109. EarthSky’s article “The Local Group is our galactic neighborhood” has a nice graphic with more names, if you want.(14 votes)
- what happen if black hole suddenly was in our solar system??🤔(4 votes)
If a black hole suddenly appeared in our solar system, it would have devastating effects on everything in the solar system. The gravity of the black hole would disrupt the orbits of the planets, and the high-energy radiation emitted by the black hole would harm any living organisms in the solar system. The black hole would eventually consume all the material in the solar system, including planets and other bodies. However, the likelihood of a black hole suddenly appearing in our solar system is very low, so this is not something that we need to worry about.(10 votes)
