A dark storm on Neptune suddenly changed direction and began to move away from almost certain death, puzzling astronomers.
NASA’s Hubble Space Telescope first saw the vortex in 2018. A year later, the storm began to head south toward Neptune’s equator, following the path of several storms in front of it. Usually, these dark spots on Neptune live for a few years before disappearing or disappearing. However, the storm mysteriously stopped south and made a sudden turn, drifting back north. At the same time, astronomers have observed a second smaller dark spot on the planet.
They theorize that this smaller “cousin” storm may be a piece of the original vortex that has broken and gone.
Related: The birth of the storm “The Great Dark Spot” on Neptune seen for the first time (Photo)
“We are excited about these observations because this smaller dark fragment is part of the process of breaking the dark spot,” said Michael H. Wong of the University of California at Berkeley. a NASA statement. “This is a process that has never been noticed. I’ve seen a few other dark spots disappear and disappear, but I’ve never seen anything disturbing, even if it’s predicted in computer simulations.”
Although Hubble has watched similar storms on Neptune for the past 30 years, astronomers have never seen such unpredictable atmospheric behavior.
The current storm, which has a distance of 7,403 kilometers (greater than the Atlantic Ocean), is the fourth dark spot Hubble has watched since 1993. These storms are high-pressure systems that rotate clockwise due to rotation of the planet (as opposed to hurricanes on Earth, which are low-pressure systems that rotate counterclockwise).
Usually, as the storms head for Neptune’s equator, the Coriolis effect, which keeps them stable, begins to weaken and the storm disintegrates. However, unlike past storms and computer simulations showing storms following a more or less straight path to the equator, the latter vortex did not migrate to this “killing zone”.
“It was really interesting to see him act the way he should, and then suddenly he stops and goes back,” Wong said in the same NASA statement. – It was surprising.
It was also surprising to find a smaller storm, which potentially erupted from the larger vortex. Astronomers informally call the smaller storm “dark spot jr”. This “jr”. it is still quite large, with a length of 6,276 km. Although researchers cannot prove that the smaller storm broke away from the larger one, Wong said that the shedding of that fragment may be enough to stop the larger storm from continuing to the equator.
This last giant storm on Neptune is the best studied so far on the planet. For example, when Hubble first saw the storm in 2018, the telescope saw bright clouds around the vortex. These clouds have now disappeared after they disappeared when the storm stopped floating south. It is possible that the lack of these clouds reveals some secrets about how dark spots evolve.
There are still a lot of mysteries surrounding the storms on Neptune, but NASA’s Outer Planet Atmospheres Legacy (OPAL) program stands to unravel these mysteries. But for now, astronomers will keep an eye on this mysterious dark spot on Neptune.
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