An international team of researchers has announced the discovery of a new type of space phenomenon. For the first time, a hurricane has been detected in Earth’s upper atmosphere. The discovery of these space hurricanes was published in Nature Communications.
Hurricanes are common features of the planets of the solar system. When particles rise or fall, a low-pressure zone can form – hurricanes form around them. This is how tropical storms in the Earth’s lower atmosphere occur. It turns out that electrically charged particles in the ionosphere can behave in the same way.
In 2014, satellites recorded a huge flowing swirl of plasma extending high into the magnetosphere. This peculiar aurora happened on August 20, 2014, lasting for about eight hours. The event took place during a period of extremely calm geomagnetic conditions, and much closer to the magnetic North Pole than the average northern lights.
It reached from 110 kilometers to 860 kilometers in altitude, and consisted of plasma with multiple spiral arms, swirling in an anti-clockwise direction at speeds up to 2,100 meters per second (6,900 feet per second). The centre, however, was almost still, just like in hurricanes at lower altitudes.
Unlike other hurricanes, however, the space hurricane rains electrons in the ionosphere. This had a stunning effect: a huge cyclone-shaped aurora borealis under the hurricane. All this lasted almost eight hours, depositing huge amounts of energy in the ionosphere.
Although we’ve never seen anything like this before, its detection suggests that space hurricanes, as they are known, could be a common planetary phenomenon.
“Until now, it was uncertain that space plasma hurricanes even existed, so to prove this with such a striking observation is incredible,” said space environment physicist Mike Lockwood of the University of Reading in the UK.
“Tropical storms are associated with huge amounts of energy, and these space hurricanes must be created by unusually large and rapid transfer of solar wind energy and charged particles into the Earth’s upper atmosphere,” Lockwood explained.
“Plasma and magnetic fields in the atmosphere of planets exist throughout the universe, so the findings suggest space hurricanes should be a widespread phenomena,” Lockwood said.
There are implications for Earth, too. Knowing that aurorae can be the product of space hurricanes, and what these aurorae look like, could help us identify other such storms in the future.
It also shows that, even when geomagnetic conditions are relatively quiet, space can whip up extreme weather that can impact life on Earth, and the skies above it.
