7. Precise Day-Night Cycle Measurements
Webb’s uninterrupted observations have enabled astronomers to determine that WASP-43b spins incredibly fast, with a complete day lasting less than 20 hours. These rapid orbital and rotational speeds are a key factor behind the planet’s dramatic temperature swings. Such precise measurements deepen our understanding of how hot Jupiters evolve and respond to their harsh stellar environments. Read more in the ESA’s exoplanet rotation summary.