Yes, all galaxies have gravity. Gravity is a fundamental force that exists everywhere in the universe, including within and between galaxies. It is responsible for holding galaxies together, as well as determining their structure and motion.
That is what has been observed, except that spiral galaxies rotate faster than would be expected based on the matter we can see. Thus we infer the existence of dark matter in the rims of these galaxies. An alternative hypothesis is that something is terribly wrong with our theory of gravity. To the best of our knowledge the rules of physics are the same no matter where you go.
Galaxies are held together by gravity. So are Solar Systems. In the case of galaxies, and galaxy clusters, it isn't entirely clear what type of masses provide this gravity - the amount of known matter is simply too small, by a factor of 5-10. For more information, do some reading on "dark matter".
Gravity is the primary force involved in the formation of galaxies after the big bang. Over time, the gravitational attraction between matter caused it to clump together, forming structures like galaxies and clusters of galaxies.
The big idea for space and time is that the universe contains matter. Gravity and energy influence the formation of galaxies, and all matter of the universe.
Yes, all galaxies have gravity. Gravity is a fundamental force that exists everywhere in the universe, including within and between galaxies. It is responsible for holding galaxies together, as well as determining their structure and motion.
That is what has been observed, except that spiral galaxies rotate faster than would be expected based on the matter we can see. Thus we infer the existence of dark matter in the rims of these galaxies. An alternative hypothesis is that something is terribly wrong with our theory of gravity. To the best of our knowledge the rules of physics are the same no matter where you go.
By definiton, "dark" matter neither emits or absorbs light. Thus, it does not effect the brightness of galaxies.
For starters, if there were no separation between two (or more) galaxies, it would be considered a single galaxies, not two or more. The reason matter is clumped together into galaxies at all (with separations in between) is because of gravity - gravity tends to do that, i.e., to clump things together.
Yes.
Galaxies are held together by gravity. So are Solar Systems. In the case of galaxies, and galaxy clusters, it isn't entirely clear what type of masses provide this gravity - the amount of known matter is simply too small, by a factor of 5-10. For more information, do some reading on "dark matter".
Gravity is the primary force involved in the formation of galaxies after the big bang. Over time, the gravitational attraction between matter caused it to clump together, forming structures like galaxies and clusters of galaxies.
Gravity is the force that attracts all matter to other matter. It is responsible for keeping the planets in orbit around the sun and holding galaxies together.
Gravity is a force between any two masses.
A crucial role. Without gravity, matter would never have gathered together, to form galaxies and stars.
Galaxies clump together in clusters and superclusters due to the force of gravity. Gravity pulls galaxies towards each other, causing them to form groups and larger structures. This clustering is a natural result of the way matter is distributed in the universe.
In theory, all galaxies originate from the Big Bang, which is the name that describes the explosion that propelled all matter into the cosmos. All galaxies are moving. All galaxies produce energy like light and gravity. Think of galaxies like you would human beings. Although very different in some ways, they are mostly the same.