Physics of Cometary Magnetospheres

  title={Physics of Cometary Magnetospheres},
  author={Tamas I. I. Gombosi},
This tutorial summarizes our present, pre-Rosetta understanding of the basic physical processes operating in cometary environments with particular attention to cometary magnetotails. Ionization of cometary gases is responsible for most plasma processes in the magnetospheres of active comets. The interaction between the superalfvenic, magnetized solar wind and cometary ions forms a number of plasma boundaries starting with the weak bow shock and continuing with the contact surface (diamagnetic… 
Hybrid modelling of cometary plasma environments - I. Impact of photoionisation, charge exchange, and electron ionisation on bow shock and cometopause at 67P/Churyumov-Gerasimenko
Context. The ESA/Rosetta mission made it possible to monitor the plasma environment of a comet, from near aphelion to perihelion conditions. To understand the complex dynamics and plasma structures
Modeled Interaction of Comet 67P/Churyumov-Gerasimenko with the Solar Wind Inside 2 AU
Periodic comets move around the Sun on elliptical orbits. As such comet 67P/Churyumov-Gerasimenko (hereafter 67P) spends a portion of time in the inner solar system where it is exposed to increased
Solar wind dynamics around a comet
Aims. We aim at analytically modelling the solar wind proton trajectories during their interaction with a partially ionised cometary atmosphere, not in terms of bulk properties of the flow but in
Hall effect in the coma of 67P/Churyumov–Gerasimenko
Magnetohydrodynamics simulations have been carried out in studying the solar wind and cometary plasma interactions for decades. Various plasma boundaries have been simulated and compared well with
Properties of the singing comet waves in the 67P/Churyumov-Gerasimenko plasma environment as observed by the Rosetta mission
Using in situ measurements from different instruments on board the Rosetta spacecraft, we investigate the properties of the newly discovered low-frequency oscillations, known as singing comet waves,
Plasma and Dust around Icy Moon Enceladus and Comet 67P/Churyumov-Gerasimenko
Saturn's moon Enceladus and comet 67P/Churyumov-Gerasimenko both are examples of icy solar system objects from which gas and dust flow into space. At both bodies, the gas becomes partly ionized and
Suprathermal electrons near the nucleus of comet 67P/Churyumov‐Gerasimenko at 3 AU: Model comparisons with Rosetta data
Observations of the coma near the nucleus of comet 67P/Churyumov‐Gerasimenko (67P) made by the IES (Ion and Electron Sensor) instrument onboard the Rosetta Orbiter during late 2014 showed that
The Evolution of the Electron Number Density in the Coma of Comet 67P at the Location of Rosetta from 2015 November through 2016 March
A comet ionospheric model assuming the plasma moves radially outward with the same bulk speed as the neutral gas and not being subject to severe reduction through dissociative recombination has pre
Comparative study of photo-produced ionosphere in the close environment of comets
Context. The Giotto and Rosetta missions gave us the unique opportunity of probing the close environment of cometary ionospheres of 1P/Halley (1P) and 67P/Churyumov-Gerasimenko (67P). The plasma


The Structure of Comets' Induced Magnetotails: Remote and in situ Observations
Ions created from the neutral comae of active comets are picked up by the solar wind and carried downstream to form induced magnetotails. These are observed remotely as comets’ ion or plasma tails.
The physics of the cometary contact surface
The contact surface, which separates outflowing cometary plasma from solar wind controlled cometary plasma, is explained in terms of a balance between the magnetic pressure gradient force and
International Cometary Explorer Encounter with Giacobini-Zinner: Magnetic Field Observations
The vector helium magnetometer on the International Cometary Explorer observed the magnetic fields induced by the interaction of comet Giacobini-Zinner with the solar wind, which consisted of two lobes, containing oppositely directed fields with strengths up to 60 nanoteslas.
Energetic ions in the environment of comet Halley
The energetic particle experiment, EPONA/EPA, carried aboard the Giotto spacecraft recorded in situ measurements of energetic charged particles on the sunward side of comet Halley, from a trajectory
A new model of cometary ionospheres
The coupled continuity, momentum, and energy equations were solved for ionospheric conditions appropriate for comet Halley at 1 AU. The numerical scheme used is such that any shock transition appears
A sharp (<104 km thick) transition from a solar wind proton dominated flow to a plasma population primarily consisting of relatively cold cometary heavy ions has been observed at a cometocentric
Dust and neutral gas modeling of the inner atmospheres of comets
This paper summarizes the present, preencounter understanding of the physical and chemical processes controlling the inner (r less than 1000 km) region of cometary atmospheres. Special emphasis was
A New Model of Cometary
The coupled continuity, momentum, and energy equations were solved for ionospheric conditions appropriate for comet Halley at 1 AU. The numerical scheme used is such that any shock transition appears
Solar wind stagnation near comets
The nature of the solar wind flow near comets is examined analytically in this paper. In particular, typical values for the stagnation pressure and magnetic barrier strength are estimated, taking
First in situ plasma and neutral gas measurements at comet Halley
We present the first in situ observations and a description of the large-scale behaviour of comet Halley's plasma environment. The PLASMAG-1 experiment, carried aboard the spacecraft Vega 1 and Vega