Supernovae that are moving away at an accelerating rate.
The evidence for the existence of dark energy can be found in the observation of supernovae that are moving away at an accelerating rate. This phenomenon was discovered by studying distant supernovae and measuring their redshift, which is a shift in the wavelength of light caused by the expansion of the universe. By comparing the observed brightness of these supernovae to their expected brightness, scientists were able to determine that the rate of expansion of the universe is increasing over time. This suggests the existence of a mysterious form of energy known as dark energy, which is believed to be causing this accelerated expansion. Therefore, the correct answer is: Supernovae that are moving away at an accelerating rate.
The evidence for the existence of dark energy is supernovae that are moving away at an accelerating rate.
