No matter how persistently bad the weather may get in your vicinity, you can always comfort yourself with the knowledge that — at the very least — you aren’t trapped within the scope of an anticyclonic storm three times the size of planet Earth. That problem likely won’t inconvenience humans until we find a way to colonize Jupiter, because the ultra-storm we’re talking about is that planet’s Great Red Spot (GRS).

However, dealing with extraterrestrial cyclones is a problem that the colonists of many local planets will face, though no storm is so visible or as long-lived as the GRS. Several planets in our solar system have observable mega-storms, with the GRS merely the largest and most famous example.

Jupiter is also home to the rather unpoetically named Oval BA storm (sometimes called Red Spot, Jr.), which appears just south of the GRS and was formed when three smaller storms called White Ovals converged. While the GRS has been observed for three centuries, Oval BA was first noticed in 2000, and the White Ovals that formed it were first recorded in 1939. Oval BA is younger and smaller than the GRS, which is to say its average diameter is “only” equal to that of planet Earth.

Outside of Jupiter, Saturn probably hosts the most well known extraterrestrial cyclones. The ringed planet’s most notable storm is the Great White Spot (GWS) — or should we say, Great White Spots. The GWS is a periodic storm that appears at roughly 28.5 year intervals, when Saturn’s northern hemisphere is tilted in the direction of the sun. The GWS is usually a few thousand kilometers across when it first appears, then stretches out to a wide latitude, occasionally encircling the entire planet. Saturn is also home to the Dragon Storm, another periodic cyclone that glows a bright orange-pink when it appears.

Venus has two unnamed pairs of mega-anticyclones, one pair near each of its poles. Mars has also been shown to experience extremely brief (perhaps only hours-long) polar cyclones, some over a thousand miles wide. Neptune, meanwhile, has both the Great Dark Spot and the Wizard’s Eye, two megastorms observed in 1989 by Voyager 2, with the former varying in size from the diameter of Earth to no bigger than all of Europe and Asia.

These storms are not only massive but intense. The GRS alone boasts peak wind speeds in the vicinity of 267 miles per hour (430 kilometers per hour), and that’s not even close to the fastest wind in the solar system.


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Which of the various extraterrestrial cyclones found in our solar system — a list which includes both Jupiter’s Great Red Spot and Saturn’s Dragon Storm — produces the fastest winds?

The fastest winds ever observed in our solar system were created by Neptune’s Great Dark Spot (GDS), which produced wind speeds in excess of 1,500 mph (2,400 kph). That’s almost 10 times faster than the minimum wind speeds necessary for a terrestrial cyclone to qualify as a Category 5 Hurricane on the Saffir-Simpson Scale. 1,500 miles per hour is also five times faster than the highest wind speeds ever observed in a terrestrial tornado, which is to say five times faster than fastest winds ever seen on Earth.

It should be noted that the GDS’s solar system-best wind speeds occurred at the edge of the GDS. In fact, the highest wind speeds in all the great planetary “spot” storms occur on their edges, as the interiors of these spots are usually stagnant air masses. In the case of the GDS, scientists theorize this storm as a massive hole in the methane cloud deck of Neptune, literally a great empty spot in the atmosphere similar to the hole in Earth’s ozone layer. Those theories may never be confirmed, as the GDS disappeared before the Hubble Telescope was scheduled to observe it in 1994.

However, the GDS — and its record-setting winds — may still rage on Neptune as a “conventional” cyclone somewhere beneath the visible cloud layer, having dissipated its great empty center. Meanwhile, a very similar phenomenon has since appeared in Neptune’s northern hemisphere, creating an extraterrestrial cyclone known as the Northern Great Dark Spot.

Finally, when referring to the windy record-breaker, scientists would prefer you be specific and call it Neptune’s Great Dark Spot or, even more precisely, Neptune’s Great Dark Spot of 1989. That’s not just because Neptune has since developed a new GDS, but because Jupiter has one as well — and it might be bigger than the Great Red Spot.

Jupiter’s GDS was first observed in 2000 by the Cassini probe. It appears and disappears for months at a time, unlike the multi-century lifespan of the Great Red Spot. Moreover, Jupiter’s Great Dark Spot sits above the planet’s northern pole — where’s it’s not so easily observed. Also, it’s invisible to the naked eye, appearing only under ultraviolet inspection. But when you see Jupiter’s GDS, it’s usually twice the diameter of Earth and can grow even larger — to diameters that eclipse even the Great Red Spot.

That’s not just some astonishing astronomic observation; it’s a meteorologically mind-boggling moment of Geek Trivia.

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