A DISCOVERY WORTH SHARING✧Science↗ A star with a regular 5.4-day rhythm John Goodricke discovered the changing brightness of Delta Cephei in 1784. The star brightens relatively quickly and fades more slowly, completing a cycle in about 5.4 days. Its changing light is a regular pattern rather than random flickering. THERE’S MORE TO DISCOVERReady for another?One small break. A fresh perspective.Get today's Breakfact ↗ OpenStax · Astronomy 2e · Variable Stars: One Key to Cosmic Distances ↗ (opens in a new tab)Share ↗