Sphere of Neptune seen. Dark blue circle with two small dark spots on the Northern portion.

Neptune’s Monster Storm

This Hubble Space Telescope snapshot of the dynamic blue-green planet Neptune reveals a monstrous dark storm (top center) and the emergence of a smaller dark spot nearby (top right). The giant vortex, which is wider than the Atlantic Ocean, was traveling south toward certain doom by atmospheric forces at the equator when it suddenly made a U-turn and began drifting back northward. The large storm, which is 4,600 miles across, is the fourth dark spot Hubble has observed on Neptune since 1993. Two other dark storms were discovered by the Voyager 2 spacecraft in 1989 as it flew by the distant planet, but they had disappeared before Hubble could observe them. Since then, only Hubble has had the sharpness and sensitivity in visible light to track these elusive features, which have sequentially appeared and then faded away over a duration of about two years each. Hubble uncovered this latest storm in September 2018.

Credits: NASA, ESA, STScI, M.H. Wong (University of California, Berkeley), and L.A. Sromovsky and P.M. Fry (University of Wisconsin-Madison)