Both Voyagers are more than 11 billion miles away from Earth, and are still communicating with NASA satellites. Very good bois, for sure.
Data currently being sent back is measurements of cosmic rays, magnetic fields, and particle data from interstellar space. The data helps us understand the boundary of the heliosphere, which is the protective bubble of particles from magnetic fields produced by the sun that envelops the planets as well as solar wind, and the transition from stellar space to interstellar.
The heliosphere is a shield for the solar system against cosmic radiation, and the data from its outer boundary may lead to an understanding into its size, shape, and structure, plus the interaction of particles entering or exiting the sphere.
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