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Two single pixel cameras, using revolutionary technology, have been used to give "live" images of a large portion of the Earth's magnetosphere.
The magnetosphere is the result of the interaction of the Earth's magnetic field, generated by the dynamo effect of the rotating core, with charged particles coming from cosmic sources; mainly the solar wind.
Most of what we know about the shape and makeup of the magnetosphere (reminiscent of a jelly fish with its head towards the Sun) comes from the comparison of theoretical calculations with local measurements made by various satellites. However, its large scale structure at any given moment has always been hidden, largely due to the fact that it does not emit visible light and that we are located within the structure itself.
To overcome this, the Interstellar Boundary Explorer (IBEX) was built, a satellite with sensors able to detect so-called Energetic Neutral Atoms. These are atoms at extreme altitude in the terrestrial atmosphere that are accelerated to large velocities by collisions with energetic charged particles in the solar wind.
By using the Energetic Neutral Atoms as tracers of the charged particles trapped in the magnetosphere, IBEX can map what is happening at any given time.
Changes in the solar wind can have large effects on the shape of the tail of the magnetosphere, where the magnetic field lines are more extended and sensitive to asymmetries in the wind.
One such effect is the explosive disconnection of parts of the plasma tail, causing the release of energy and high energy particles when the magnetic field lines reconnect.
One of these events, resulting in the formation of a "plasmoid", actually appears to be visible in the first IBEX image of the magnetosphere (above). The image was made by a team of researchers led by David McComas, principal investigator of the mission.
The ability to systematically observe events such as these takes us one step closer to forecasting so-called space weather, and therefore make any space based activity much safer.
The results of the work of McComas and co-workers were published 2 days ago in the Journal of Geophysical Research.
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