1. Initial Close Encounter:
As two galaxies approach each other, their gravitational interactions begin to affect each other's structure. Gas clouds can start getting pulled from one galaxy into the other. This can trigger bursts of star formation along the tidal tails created during the encounter.
2. Gas Compression and Starbursts:
As the galaxies continue to come closer, gas clouds from both galaxies collide, causing compression. This compression leads to enhanced star formation regions within the galaxies, resulting in the formation of new stars.
3. Gravitational Interactions and Merging:
The gravitational interactions between the two galaxies can lead to distortions in their shapes and structures. Gas, stars, and dark matter within the galaxies may redistribute and mix. Over time, the galaxies can merge into a single, larger galaxy or form a complex structure.
4. Tidal Disruptions and Formations:
The strong gravitational forces during the collision can cause tidal disruptions in both galaxies. Stars might be pulled out of their original orbits, leading to the formation of star streams and tidal tails that extend far from the main body of the galaxies.
5. Supermassive Black Holes:
If both galaxies have supermassive black holes at their centers, they may also interact with each other. In the event of a merger, the two black holes may form a binary system or even eventually merge into a single, more massive black hole.
6. Morphological Transformation:
The collision can lead to significant changes in the galaxies' morphologies. The resulting galaxy might have a peculiar shape, such as an elliptical, lenticular, or irregular form, depending on the details of the collision.
7. Stellar Encounters and Gravitational Scattering:
During the collision, stars from one galaxy can encounter stars from the other. Close stellar encounters can lead to gravitational interactions that can alter the stars' trajectories, velocities, and energies.
8. Merger Remnant:
After the collision and merging process, the end result could be a new, larger galaxy with combined mass and properties from the original two galaxies. The structure, dynamics, and star formation history of the merger remnant depend on the specific details of the collision.
It's worth noting that galactic collisions are complex events, and the exact outcome can be influenced by numerous factors. Observations of merging galaxies and simulations play a vital role in understanding the processes involved in such collisions and the evolution of galaxies over cosmic time.
