The birth and growth of a solar wind cavity around a comet -- Rosetta observations

Abstract

The Rosetta mission provided detailed observations of the growth of a cavity in the solar wind around comet 67P/CG. As the comet approached the Sun, the plasma of cometary origin grew enough in density and size to present an obstacle to the solar wind. Our results demonstrate how the initial slight perturbations of the solar wind prefigure the formation of a solar wind cavity, with a particular interest placed on the discontinuity (solar wind cavity boundary) passing over the spacecraft. The slowing down and heating of the solar wind can be followed and understood in terms of single particle motion. We propose a simple geometric illustration that accounts for the observations, and shows how a cometary magnetosphere is seeded from the gradual steepening of an initially slight solar wind perturbation. A perspective is given concerning the difference between the diamagnetic cavity and the solar wind cavity.

8 pages, 3 figures

References in corpus (5)

• The microphysics of collisionless shock waves
• Observation of a New Type of Low Frequency Waves at Comet 67P/Churyumov-Gerasimenko
• Mass loading at 67P/Churyumov-Gerasimenko: a case study
• CME impact on comet 67P/Churyumov-Gerasimenko
• Mass-loading of the solar wind at 67P/Churyumov-Gerasimenko -- Observations and modelling

Cited by in corpus (12)

• Measurements of the electrostatic potential of Rosetta at comet 67P
• Solar wind dynamics around a comet - A 2D semi-analytical kinetic model
• Solar wind charge exchange in cometary atmospheres. I. Charge-changing and ionization cross sections for He and H particles in H${}_2$O
• ROSINA ion zoo at Comet 67P
• The root of a comet tail - Rosetta ion observations at comet 67P/Churyumov--Gerasimenko
• Solar wind charge exchange in cometary atmospheres. II. Analytical model
• Momentum and pressure balance of a comet ionosphere
• Development of a cometosheath at comet 67P/Churuyumov-Gerasimenko: A case study comparison of Rosetta observations
• Solar wind dynamics around a comet: The paradigmatic inverse-square-law model
• Dawn-dusk asymmetry induced by the Parker spiral angle in the plasma dynamics around comet 67P/Churyumov-Gerasimenko
• Refractory elements in the gas phase for comet 67P/Churyumov-Gerasimenko
• Upper Limits for Emissions in the Coma of Comet 67P/Churyumov-Gerasimenko Near Perihelion as Measured by Rosetta's Alice Far-Ultraviolet Spectrograph