the universe's galaxies have evolved since what point in time?
approximately 50 million years ago, after initial clumps of material were formed
800 million years ago, when gas concentration were optimal for galaxy formation
13.8 billion years ago, right after the universe formed
23.4 billion years ago, when the universe first formed
The universe's galaxies have evolved since approximately 13.8 billion years ago, right after the universe formed.
which of the following is an accurate description of cosmic microwave background radiation?
CMB is remnant radiation from the big bang
CMB increases across the universe
CMB is constantly generated by stars
CMB produces differing temperatures across the universe
The accurate description of cosmic microwave background (CMB) radiation is that it is remnant radiation from the big bang.
which proportion of the universe's galaxies can be seen from earth
25 percent
10 percent
lees than 1 percent
nearly half
Less than 1 percent of the universe's galaxies can be seen from Earth.
which was used to create the first image of a black hole?
ultraviolet light
visible light
x-rays
radio waves
Radio waves were used to create the first image of a black hole.
why are most stars not destroyed in a galaxy collision?
Most stars are not destroyed in a galaxy collision because the distances between individual stars are extremely vast compared to the size of the galaxies themselves. So, when galaxies collide, the chances of any two stars physically colliding with each other are very small. Additionally, the gravitational interactions between stars and other celestial bodies during a galaxy collision are usually not strong enough to cause the destruction of stars. Instead, the gravitational forces can cause stars to change their orbits or be ejected from their original galaxies, but actual stellar destruction is rare.
The universe's galaxies have evolved since approximately 13.8 billion years ago, right after the universe formed.
To determine this, we rely on scientific evidence gathered from various sources. One crucial piece of evidence is the measurement of the cosmic microwave background radiation, which is leftover radiation from the early stages of the universe. By analyzing this radiation, scientists have been able to determine the age of the universe, which is approximately 13.8 billion years.
Galaxies began forming shortly after the universe's inception. The initial clumps of material started to come together approximately 50 million years after the Big Bang, but the process of galaxy formation took much longer. It wasn't until around 800 million years after the Big Bang that the gas concentrations in the universe reached an optimal level, allowing for the efficient formation of galaxies.
Therefore, while there have been important milestones in the evolution of galaxies, such as the point when gas concentrations were optimal for galaxy formation around 800 million years ago, the overall evolution of the universe's galaxies has been ongoing since approximately 13.8 billion years ago.