Observations of a Radial Density Gradient in the Very Local Interstellar Medium by Voyager 2

  title={Observations of a Radial Density Gradient in the Very Local Interstellar Medium by Voyager 2},
  author={W. S. Kurth and D. A. Gurnett},
  journal={The Astrophysical Journal Letters},
Beginning on 2020 June 19, at a heliocentric distance of 124.2 au, the Voyager 2 Plasma Wave Science instrument began to observe radio emissions followed by electron plasma oscillations in its 3.11 kHz spectrum analyzer channel. Plasma oscillations at this frequency imply an electron density in the range of 0.12 cm−3 ± 15%, although some response in the 1.78 kHz channel near the peak of the plasma oscillations suggest a density of 0.087 cm−3 ± 8%. Shortly after Voyager 2 crossed the heliopause… 

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