In Situ Observations of Interstellar Plasma with Voyager 1

@article{Gurnett2013InSO,
  title={In Situ Observations of Interstellar Plasma with Voyager 1},
  author={Donald A. Gurnett and William S. Kurth and Leonard F. Burlaga and Norman F. Ness},
  journal={Science},
  year={2013},
  volume={341},
  pages={1489 - 1492}
}
Finally Out Last summer, it was not clear if the Voyager 1 spacecraft had finally crossed the heliopause—the boundary between the heliosphere and interstellar space. Gurnett et al. (p. 1489, published online 12 September) present results from the Plasma Wave instrument on Voyager 1 that provide evidence that the spacecraft was in the interstellar plasma during two periods, October to November 2012 and April to May 2013, and very likely in the interstellar plasma continuously since the series of… 

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