When Jupiter recently re-emerged into view, astronomers noticed that it was missing one of its dominant features: the southern band, a dark wide stripe on the gas giant.
This is not the first time it has done so while being observed. In 1973, the Pioneer space probe passed by and scientists noticed that it was missing then too. Later, in the 90s, it vanished temporarily.
It is theorized that white clouds in the upper atmosphere of the planet might be obscuring the darker belt region. Recently the planet has been experiencing numerous other sudden changes: bands changing colors, and random appearance of spots.