Enlarge / Enhanced Juno image of Jupiter’s Great Red Spot in 2018. It is likely not the same one observed by Cassini in the 1600s. (credit: Gerald Eichstadt and Sean Doran/CC BY-NC-SA) The planet Jupiter is particularly known for its so-called Great Red Spot, a swirling vortex in the gas giant's atmosphere that has been around since at least 1831.