Which factor is essential to the initial formation of galaxies, for either of the theories describing galaxy evolution? (1 point)
O The force of orbiting stars generates collisions.
O Gravity acts on existing material, shaping it into a new form.
O Small lumps of material merge into larger clumps.
O Massive gas and dust clouds collapse.
O Massive gas and dust clouds collapse.
The factor that is essential to the initial formation of galaxies, according to both theories describing galaxy evolution, is "Massive gas and dust clouds collapse."
The factor that is essential to the initial formation of galaxies, according to both theories describing galaxy evolution, is the collapse of massive gas and dust clouds. To understand this, we can look at the process of galaxy formation.
In the early universe, shortly after the Big Bang, there were slight density variations in the distribution of matter. These density variations were the result of quantum fluctuations during the inflationary period. Over time, these fluctuations grew larger due to the force of gravity.
As gravity pulled matter together, the regions with slightly higher density attracted more matter towards them, forming dense pockets. These pockets eventually collapsed under their own gravitational pull, causing the gas and dust within them to come together even more tightly.
As the collapse continued, the gas and dust clouds grew denser and hotter at their centers. Eventually, the core of these clouds became hot enough to trigger nuclear fusion, which led to the formation of stars. The surrounding material also began to settle into a rotating disk around the central mass, which is known as a protogalactic disk.
Within this protogalactic disk, small lumps of material, such as gas clouds and stars, merged together due to the force of gravity. Over time, these mergers continued, resulting in the growth of larger clumps of material, including galaxies.
Therefore, the essential factor in the initial formation of galaxies is the collapse of massive gas and dust clouds, which eventually leads to the merging of smaller clumps and the formation of galaxies.