美国国家公共电台 NPR--An explanation of reports that part of the sun has broken off（在线收听）

An explanation of reports that part of the sun has broken off

Transcript

A part of the sun has broken off and was swept up in a polar vortex. Scientists say it's not as dangerous as it sounds.

ASMA KHALID, HOST:

Did a piece of the sun really break off recently? A massive solar flare has raised that question, and Scott McIntosh took it on. He's deputy director at the National Center for Atmospheric Research, and he says the answer is yes.

SCOTT MCINTOSH: Bits of the sun of various sizes break off all the time. You know, the sun's outer atmosphere is like a churning, bubbling cauldron, right? And occasionally, stuff heats and cools and gets ejected out of the atmosphere. Some of it falls back down and cools, and some of it goes off into interplanetary space.

STEVE INSKEEP, HOST:

McIntosh says plasma can form a large loop on the sun's surface. When that happens, it's called a solar prominence, and they are common. Although, this recent one that's getting all the attention was different.

MCINTOSH: Sure, we see lots of these guys on the edge of the sun, and we see them doing their little circular dance. But this guy, it was the whole thing, right? The whole thing lifted off and went around.

INSKEEP: I love the personification. This guy lifted off. Now McIntosh is wondering what caused this unique solar vortex.

MCINTOSH: We have a strong suspicion that what happens at the sun's poles - because it reverses its magnetic field every 22 years, about every 11 years, there's a sign change at the poles. Something in that polar reversal process, we call it, is tied to how the sun's magnetic field works, which is the thing that propagates through the whole solar system.

KHALID: While scientists keep looking for answers, do not be alarmed. McIntosh assures us this stuff poses no risk to us people down here on Earth.

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