Which is evidence for the existence of dark energy?(1 point)
Responses
Pulsars that seem to be moving closer at an accelerating rate.
Supernovae that are moving away at an accelerating rate.
Black holes that are expanding at a constant rate.
Galaxies that are rotating at a constant rate.
Supernovae that are moving away at an accelerating rate.
The evidence for the existence of dark energy is provided by Option 2: Supernovae that are moving away at an accelerating rate.
To understand why this is evidence for dark energy, we need to look at the concept of the expansion of the universe. Scientists have observed that the universe is expanding, meaning that galaxies and other celestial objects are moving away from each other. They initially thought that this expansion was slowing down due to the gravitational pull between galaxies. However, observations of distant supernovae revealed a surprising result - these supernovae were moving away at an accelerating rate, which implies that there must be some unknown force counteracting the gravitational attraction and causing the expansion to accelerate.
This unknown force is called dark energy. Dark energy is a hypothetical form of energy that is thought to make up about 68% of the total energy content of the universe. It is believed to be responsible for the accelerating expansion of the universe. Although not directly detected, its existence is inferred based on the observations of the accelerating movement of distant supernovae.
Therefore, the observation of supernovae moving away at an accelerating rate provides evidence for the existence of dark energy.