Jupiter’s Great Red Spot, a storm larger than Earth, has raged for at least 350 years—but it’s slowly shrinking. In the 1800s, it was over 40,000 km wide; today, it’s less than half that size. Scientists don’t know if it will disappear entirely or stabilize at a smaller size. Either way, the planet’s atmosphere is constantly shifting, meaning future astronomers may see a very different Jupiter.