If on a clear and starry night in mid-May you had trained a high-powered telescope on just the right part of Jupiter, you would have seen something very, very strange. The Great Red Spot, one of our solar system’s most famous features, would have appeared to be slowly unraveling. You would have seen the swirling storm system casting off ribbons of rose-colored gas like petals in the wind. It would have been beautiful.
Earlier this year, dozens of die-hard amateur astronomers across the globe began noticing that the Great Red Spot’s ordinarily ovoid figure looked distorted. By April, it seemed to be shedding red flakes. In May, that flaking grew so extreme that the spot looked as though it might disintegrate.
The amateur community, a tight-knit group that regularly communicates and shares photos over social media, was charged with excitement and anxiety. It had never seen anything like this before, and members worried what it might mean. On a warm Australian night in early May, the longtime amateur and software engineer Anthony Wesley was floored when his telescope captured an image of a bright streamer curling away from the spot. That, he thought, is not something you see every day.
Humans have been observing the Great Red Spot since the invention of the telescope in the 1600s, and at its peak, the storm was three times wider than the Earth. Since the late 19th century, though, it has been shrinking, slowly but steadily. In 2012, amateur astronomers noticed that its diminution had accelerated. And in May, when they saw it flaking, they feared that it might be on the verge of extinction.