It happens all over the universe, but close to home, it occurs during solar flares, coronal mass ejections and when solar winds interact with the Earth's magnetic field, causing aurorae. In order to study and create a 3D map of the mysterious phenomenon, NASA's Magnetospheric Multiscale mission will send four spacecraft to space, which will position themselves in a pyramid.
A single rocket will carry all four (stacked on top of each other) to their destination, as you can see in the demo video of the launch below. Each one is designed to break free from the stack once the rocket reaches orbit, and to deploy its "booms" (or foldable, extendable limbs equipped with sensors needed for the study) once it gets in position. Barring delays, these spacecraft will launch in March 2015 to seek out parts near our planet where magnetic reconnection typically occurs, so that we may understand it better.
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