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We finally figured out what’s been making a huge greek letters by the north and south
poles. My money’s on frat guys.
Hey there my shining beacons, Julian here for DNews. I’m sure you’ve all heard of
the Aurora Borealis, or if you’re a viewer south of the equator, the Aurora Australis.
They’re dazzling natural light shows that happen when charged particles like electrons
and protons from the solar wind excite oxygen and nitrogen in our upper atmosphere.
Normally the Aurorae can occur 65-70 degrees north or south of the equator but they can
happen at higher latitudes. Occasionally these take the shape of the greek letter theta and
we had no idea why.
You see, the earth is surrounded by a magnetic field thanks to its spinning iron core. These
magnetic field lines loop between the north and south pole and form the magnetosphere.
The magnetosphere deflects the charged particles of the solar wind, and it’s the reason we
have an atmosphere while poor little Mars has had its almost totally stripped away.
But the field lines don’t all connect, and plasma rides the broken ones down to the ionosphere,
getting faster and more dense. When it meets our air energizes the gases, which then radiate
that energy away as light. Normally the plasma that moves to the higher latitudes cools but
sometimes it gets more energetic and makes these theta auroras.
Combining data from the European Space Agency’s Cluster satellites and NASA’s IMAGE satellites,
the mystery of why this cold plasma heats up and forms this shape has been solved. As
it turns out this plasma gets trapped when broken field lines close, and it causes them
to become relatively hot again. See what you can do when you work together?
It’s another nifty trick of nature and I don’t care how good your fireworks are on
new years, nothing beats charged particles from 150 million kilometers away traveling
down a magnetic funnel to make green and red ribbon light shows in the sky.
If you’re a crazy person like Trace then you want to shoot rockets at everything. He
explains why the Aurora should be one of those things over here.
Is there another natural occurrence that boggles your mind? Do you want us to look into some
other mystery of nature? Let us know in the comments and I’ll see you next time on DNews.