Kepler-21: A PlanetaryKepler-21: A PlanetaryStudyKepler-21 b.Exploring Kepler-21 and its exoplanetEarth and Planetary AstrophysicsInsights into Kepler-21 and Its ExoplanetA look at the unique features of Kepler-21 and Kepler-21 b.2025-06-28T03:03:48+00:00 ― 5 min read