A team of researchers has just detected on the Sun a strange and huge circular filament of solar plasma breaking off its surface and circling its north pole like a powerful tornado. Something never seen until now and whose origin is completely unknown.
“Let’s talk about the polar vortex – said the space meteorologist Tamitha Forest on Twitter by sharing some video sequences taken by NASA’s Solar Dynamics Observatory (SDO).
Talk about Polar Vortex! Material from a northern prominence just broke away from the main filament & is now circulating in a massive polar vortex around the north pole of our Star. Implications for understanding the Sun’s atmospheric dynamics above 55° here cannot be overstated! pic.twitter.com/1SKhunaXvP
— Dr. Tamitha Skov (@TamithaSkov) February 2, 2023
Material from a northern bulge has just broken away from the main filament and is now circling in a large vortex around our star’s north pole. The implications for understanding the atmospheric dynamics of the Sun above 55° latitude here cannot be overstated.”
Other solar physicists have shared Skov’s enthusiasm about this unusual phenomenon. But what exactly is it, and why might it be important? Asked by Space.com, the solar physicist Scott McIntoshdeputy director of the National Center for Atmospheric Research in Boulder, Colorado, said that while he had never seen a vortex like this, “something strange is happening” at 55 degrees latitude from the Sun on a clockwork basis once every cycle. solar, the 11-year period characterized by the ebb and flow in the generation of eruptions and sunspots.
It therefore seems no coincidence that the strange filament mentioned by Skov, which McIntosh describes as ‘a hedge in the solar plasma’, appears at exactly 55º latitude around the Sun’s polar coronas every 11 years. Scientists know that the phenomenon is somehow related to the reversal of the solar magnetic field (which happens once every cycle), but they have no idea what is driving it.
“Once in every solar cycle,” explains McIntosh, “this ‘plasma hedge’ forms at 55 degree latitude and begins to march toward the solar poles. It is something very curious. But a big question hangs over him. Why does it only move towards the pole once and then disappear and then magically return three or four years later in exactly the same region?”
Scientists have regularly watched filaments break away from this pole-hugging ‘plasma hedge’, but never before have they seen it form such a polar vortex. The Sun’s polar regions are known to play an important role in generating the star’s magnetic field, which in turn drives the 11-year activity cycles.
The downside is that our spacecraft can’t study what’s going on there in detail because, McIntosh explains, “we can only observe the »Sun from the plane of the ecliptic (the plane in which the planets orbit)«. The European Space Agency’s Solar Orbiter mission may be able to shed some more light on this strange phenomenon, as it is taking images of the Sun from inside the orbit of Mercury and its orbit will be tilted by as much as 33 degrees over the next few years. next years. Possibly enough to clear up the mystery of the polar vortex, although it will most likely take an entirely new mission to get it done.