What are Galactic tides?

About Galactic tides:

• It is a tidal force experienced by objects subject to the gravitational field of a galaxy such as the Milky Way. 
• They are caused by gravitational forces within a galaxy, arising in the interactions between celestial objects like stars and gas clouds.
• Effects of Galactic tides
  • These tidal forces influence various aspects of a galaxy’s evolution.
  • They can reshape a galaxy structure by creating tidal tails and bridges, promoting star formation, and disrupting smaller star systems.
  • They also disrupt the orbits of stars, leading to long-term changes in galactic structure.
  • Galactic tides also have a say in the ways in which proximate galaxies do and don’t interact.
  • Researchers have observed the closest galaxy to the Milky Way, the colossal Andromeda, and found that tidal streams near its edges could be signatures of dwarf galaxies that were later devoured.
  • Galactic tides also affect the supermassive black holes at galaxy centres, leading to events that change the ways in which these cosmic beasts interact with nearby stars. 

Q1) What is black hole?

A black hole is a region in space where the gravitational pull is so strong that nothing, not even light, can escape from it. This phenomenon occurs when a massive star collapses under its own gravitational forces or when two massive objects merge, creating a singularity – an infinitely dense point at the center of the black hole.

Source: Galactic tides: Pushing and pulling the heavens