In Situ Observations of Interstellar Plasma with Voyager 1

2013/09/13 by D. A. Gurnett, W. S. Kŭrth, L. F. Burlaga +1 · 10 citations
Physics and Astronomy · #Solar and Space Plasma Dynamics #Ionosphere and magnetosphere dynamics #Astro and Planetary Science

paper · doi:10.1126/science.1241681

openalex publication_date 2013/09/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/31

Abstract

Launched over 35 years ago, Voyagers 1 and 2 are on an epic journey outward from the Sun to reach the boundary between the solar plasma and the much cooler interstellar medium. The boundary, called the heliopause, is expected to be marked by a large increase in plasma density, from about 0.002 per cubic centimeter (cm(-3)) in the outer heliosphere, to about 0.1 cm(-3) in the interstellar medium. On 9 April 2013, the Voyager 1 plasma wave instrument began detecting locally generated electron plasma oscillations at a frequency of about 2.6 kilohertz. This oscillation frequency corresponds to an electron density of about 0.08 cm(-3), very close to the value expected in the interstellar medium. These and other observations provide strong evidence that Voyager 1 has crossed the heliopause into the nearby interstellar plasma.

Citations

• Oscillations in Ionized Gases

Cited by

• THE ENERGY-DEPENDENT POSITION OF THE IBEX RIBBON DUE TO THE SOLAR WIND STRUCTURE
• Persistent Plasma Waves in Interstellar Space Detected by Voyager 1
• Observations of a Radial Density Gradient in the Very Local Interstellar Medium by Voyager 2
• THREE-DIMENSIONAL KINETIC-MHD MODEL OF THE GLOBAL HELIOSPHERE WITH THE HELIOPAUSE-SURFACE FITTING
• Three-dimensional Features of the Outer Heliosphere Due to Coupling between the Interstellar and Heliospheric Magnetic Field. V. The Bow Wave, Heliospheric Boundary Layer, Instabilities, and Magnetic Reconnection
• Magnetic Turbulence Spectra and Intermittency in the Heliosheath and in the Local Interstellar Medium
• Modeling Shocks Detected by Voyager 1 in the Local Interstellar Medium
• Time-dependent solar modulation of cosmic rays from solar minimum to solar maximum
• Donald Gurnett [wikipedia]
• Voyager 1 [wikipedia]

Related

• Observations of a Radial Density Gradient in the Very Local Interstellar Medium by Voyager 2
• Two recent kHz outer heliospheric radio emissions seen at Voyager 1-What are the interplanetary events that trigger them and where are these events when the radio emissions start?
• A Galactic Cosmic Ray Electron Intensity Increase of a factor of up to 100 At Energies between 3 and 50 MeV in the Heliosheath between the Termination Shock and the Heliopause Due to Solar Modulation As Measured by Voyager 1
• A Very Local Interstellar Spectrum for Galactic Electrons
• Cosmic electron spectra by the Voyager instruments and the Galactic electrostatic field