Neptune dark spot: inarguably the galaxy’s most beautiful

I tend to feel sorry for the ice giants. When it comes to the outer solar system, its gas giants, from the colossal, comet-perturbing Jupiter and Saturn, inarguably the galaxy’s most beautiful seismometer, understandably soak up plenty of the media’s attention. Neptune, and to a lesser extent Uranus – largely thanks to its own name and convenient atmospheric composition – are comparatively underappreciated.

Fortunately, a new study serves to remind us just how enthralling these distant planets can be. As reported in today’s edition of Geophysical Research Letters, scientists from NASA’s Goddard Space Flight Center and the University of California Berkeley have used Hubble’s images to chronicle the formation of a new dark vortex on Neptune, which became fully visible in 2018.

Although Hubble has observed spots travelling around Neptune before, this is the first time that the space telescope has documented the birth and development of one, which began in 2016. This work will catalyse our comprehension of one of the least understood planets in our cosmic backwater, while also readying us for encountering exoplanets a little bit like it far out there in the dark, strange beyond.

Neptune, like its gas giant comrades, is no stranger to giant storms. When Voyager 2 flew past Neptune in 1989, it spotted an Earth-sized vortex in its southern hemisphere. The so-called Great Dark Spot was accompanied by a somewhat smaller vortex in the same part of the planet, which was dubbed Dark Spot 2.