Mondo Knows Facts
The expansion of the universe is accelerating over cosmic time
Dark energy pushes distant galaxies apart at ever-increasing speeds
In 1998, observations of distant Type Ia supernovae revealed that the expansion rate of the universe is not slowing down under gravity but accelerating. Astrophysicists attribute this cosmic acceleration to dark energy, a pervasive repulsive pressure that accounts for roughly 68 percent of cosmic energy density.
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Tags: dark energy, expansion, universe
The expansion of the universe is accelerating over cosmic time: the short answers
- Where does this come from, and can I check it?
- Dark energy pushes distant galaxies apart at ever-increasing speeds. The figure is taken from ESA, which is linked in full on this page. Every fact on Mondo Knows names its source rather than repeating an unsourced claim.
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