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Light Tails and Magnetic Fields

Back after a three-day weekend! What better way to start off the week than with cool animations? The video above shows the Earth's magnetic field lines reconnecting with the magnetotail, a magnetic region with a shape similar to an empty sock filled with air on a windy day. The reconnection causes a vehement release of magnetic energy into the atmosphere, creating the famous display of color in the night sky known as the Northern Lights or polar auroras.

Scientists recently observed the event for the first time, using a network of 5 satellites known as THEMIS. They discovered that the reconnection is caused by a build-up of magnetic energy into kinetic energy and heat inside the Earth's atmosphere. Charged particles then speed down the magnetosphere headed for Earth, where they collide with the atmosphere, bursting into bright flares.


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