⚙️ how
How do scientists know that the universe has dark energy?
SpaceCosmology
Quick Answer
They study how the expansion of the universe changes over time. Observations of distant supernovae showed that expansion is accelerating, which points to dark energy.
The Full Story
In the late 1990s, two teams studying Type Ia supernovae found that distant explosions were dimmer than expected, implying the universe’s expansion is speeding up. This discovery suggested the presence of a repulsive cosmic component now called dark energy. Measurements from the cosmic microwave background and large-scale structure support the same picture. Dark energy is currently thought to make up about 68% of the universe’s total energy content.
Key Facts
1.Accelerating expansion was announced in 1998
2.Dark energy is estimated to be about 68% of the universe
3.Type Ia supernovae are key standard candles
YouTube Angle
Suggested video title for this topic:
"How the universe learned to speed up"