One model of galaxy formation occurs when sections of gas clouds collapse into small pieces and then merge into larger pieces due to gravity. The Milky Way is an example of the _____ model or the ______ model.
inside-out bottom-up
outside-in top-down
One model of galaxy formation occurs when sections of gas clouds collapse into small pieces and then merge into larger pieces due to gravity. The Milky Way is an example of the inside-out model or the bottom-up model.
The Milky Way is an example of the inside-out or top-down model of galaxy formation.
The Milky Way is an example of the inside-out model or the bottom-up model of galaxy formation.
To understand why, let's break down the two options:
1. Inside-out model: In this model, galaxy formation starts from the inside and expands outward. It suggests that the central regions of a galaxy form first, followed by the gradual addition of material to the outer regions. This model explains the formation of a galaxy like the Milky Way, where the central bulge and the older stellar population were formed earlier than the spiral arms and the disk structure.
2. Bottom-up model: In this model, smaller structures such as dwarf galaxies form first, and then they merge together to form larger galaxies. This model suggests that galaxy formation begins with the aggregation of smaller building blocks, which eventually build up the main galaxy. The Milky Way has indeed undergone multiple merger events with smaller satellite galaxies, which aligns with the bottom-up model.
Therefore, the Milky Way is an example of both the inside-out and the bottom-up models of galaxy formation.