Observations of white dwarf supernovae, particularly Type Ia supernovae, provide the primary evidence for the accelerating expansion of the universe. The unexpectedly faint brightness of distant supernovae suggests the influence of dark energy, driving the accelerated cosmic expansion. This evidence has been crucial in shaping our understanding of the universe's dynamics.
The primary form of evidence that has led astronomers to conclude that the expansion of the universe is accelerating is observations of white dwarf supernovae. Specifically, studies of Type Ia supernovae at large distances have revealed that their observed brightness is fainter than expected, indicating an accelerated expansion rate. This unexpected dimness is attributed to dark energy, a mysterious force driving the accelerated expansion of the universe.