The standard model of cosmology – our leading theory of cosmic evolution – suggests that dark energy is constant throughout the universe and over time, making it a fundamental property of space. If it were constant, the mysterious dark energy, which makes up as much as 70 percent of the universe, would push away all stars and galaxies. However, the most comprehensive survey of the universe’s cosmic history suggests that dark energy, also known as the hypothetical “antigravity” force, may evolve over time rather than remain constant, pointing to a less lonely future for the universe’s inhabitants.