NASA's MMS (Magnetospheric Multiscale spacecraft) encountered a surprising phenomenon reported in a 2018 article in Nature. As the videos below explain, magnetic reconnection occurs when crossed magnetic field lines "snap", slinging nearby particles away at high speeds. Reconnection events are associated with allowing ionized particles to leak into Earth's poles, causing auroras. But in 2018, scientists uncovered a new region where reconnection can occur -- in turbulent plasma in the magnetosheath (boundary between the magnetosphere and the solar wind). This chaotic region in near-Earth space undergoes magnetic reconnection, as confirmed by the MMS spacecraft. So why is this news? Compared to standard reconnection observed in prior years, this newly-observed process spans only a couple of miles within turbulent plasma -- much different from reconnection in the magnetotail, shown in videos directly below.

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The phenomenon called magnetic reconnection was confirmed for the first time in the 2010's by NASA's THEMIS project (Time History of Events and Macroscale Interactions during Substorms). The phenomenon was observed in the magnetotail, the elongated extension of Earth's magnetosphere -- where violent eruptions release trapped energy. In the process, high energy ionized particles can be released and "leak" into Earth's poles, the main source of the polar aurora.

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This 45 second video from NASA is a very effective animation showing ionized solar wind (generated by the sun) barreling toward Earth, being deflected by Earth's magnetic field, and undergoing a magnetic reconnection event as the ionized particles move along the radiation belts that flow around Earth's magnetosphere. The video does an especially good job of modeling how the high-energy ionized particles "leak" into Earth's poles to produce auroras.

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This 5-minute video is the clearest explanation/illustration we've found of the three right hand rules. It shows how to predict direction of a magnetic field in a current-carrying wire, in free-moving charges, and in a solenoid. Veteran physics instructor James Lincoln is known for supporting concepts with creative demonstrations and this video is no exception. He shows us a strong magnet interacting with aluminum foil, an electric "swing", AC and DC current, and a magnet falling through a copper tube as viewed with magnetic viewing film. At each step, he shows how to place your right hand correctly.

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This 8 minute video could be ideal for students who are struggling with how to correctly twist their thumb and fingers to use the right-hand rule......but are too embarrassed to admit it in class. Veteran HS teacher Paul Anderson does a great job in this short tutorial, which combines verbal explanations with sketches, video, and magnetic force diagrams. Students can practice alongside Mr. Anderson to get it right as they view different representations of a particle moving through a magnetic field.

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This 4-minute video explores the work of plasma physicist Jack Scudder, who figured out how spacecraft can hunt down gateways (portals) that link the magnetic field of Earth to that of the sun. These portals create an "uninterrupted" path between our planet and the sun's atmosphere. They open and close several dozen times a day. So, where ARE these portals? Watch the video to learn how NASA utilized Scudder's discovery to pinpoint them. Solar energetic particles can flow through these portals, causing geomagnetic events. Without them, there would be no auroras. Note to Instructors: Scudder's work was instrumental in guiding the NASA Magnetospheric Multiscale mission (MMS), which used special spacecraft to discover that portals form via the process of magnetic reconnection. View two MMS videos in links above. Our understanding of this phenomenon continues to evolve.

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