Recent observations of the very high-redshift Universe, using Supernovae Type Ia as standard candles, have revealed what ground-breaking discovery?

Recent observations of the very high-redshift Universe using Supernovae Type Ia as standard candles have revealed the accelerating expansion of the Universe. This groundbreaking discovery, made in the late 1990s, provided strong evidence for the existence of dark energy, an unknown form of energy responsible for this acceleration. It revolutionized our understanding of the universe's expansion and raised new questions about the fundamental properties of space, time, and energy.