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What force holds galaxies together?
Question Date: 2019-10-16
Answer 1:

The same force the keeps you on the earth- gravity!

Anything that has a mass will exert/experience a force of gravity. So while the stars and planets in a galaxy are very far away, they are very large and can still exert enough gravitational force on one another to keep the galaxy together. In theory, a faraway star exerts a force of gravity on you, it is just so small compared to the force that earth exerts that you do not notice it.

Answer 2:

Galaxies are held together by gravity. However, the matter that exerts this gravity is mostly dark matter rather than stellar matter.

Answer 3:

I'm reading a book that says Kepler thought gravity held stars and planets together, and Galileo thought Kepler's idea was crazy. They didn't have the word for gravity yet, but Kepler understood that force.

From ScienceLine:
What holds galaxies together? Gravity. All of the stars of a galaxy are all attracted to each other. This attraction is weak because the stars are very far apart, but it is enough to keep the galaxies together.

Answer 4:

Gravity. Anything with mass has gravity. Gravity gets stronger with mass and weaker with distance. The Earth pulls on our bodies, keeping us from floating away. Much in the same way the Sun pulls on the planets. This keeps the planets in orbit. Fun fact, the moon's gravity causes the tides.

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