Search Publications
Cluster observations of fast magnetosonic waves in the heliosphere current sheet
Dai, Lei; Wygant, John R.; Cattell, Cynthia A. +4 more
We present Cluster spacecraft observations of large-amplitude (δ|B|/|B|∼1) fast-mode magnetosonic waves in the heliospheric current sheet (HCS). The crossings of the HCS and the associated heliospheric plasma sheet (HPS) are encountered by Cluster in the near-Earth solar wind and by ACE upstream of Earth. Multiple current layers are detected in co…
Dayside episodic ion outflow from Martian magnetic cusps and/or magnetosheath boundary motion associated with plasma oscillations
Gurnett, D. A.; Lundin, R.; Winningham, J. D. +4 more
The radar sounder on the Mars Express Spacecraft is able to make measurements of electron densities in the Martian ionosphere from both local electron plasma oscillations and remote soundings. A study of thousands of orbits shows that in some cases the electron plasma oscillations disappear and reappear abruptly near the upper boundary of the days…
Solar wind-driven thermospheric winds over the Venus North Polar region
Fedorov, A.; Barabash, S.; Lundin, R. +3 more
Data from the neutral particle imager (NPI) on Venus Express reveals the presence of a persistent +Y (Venus Solar-Oriented) flow of Energetic Neutral Atoms (ENAs) in the Venus polar thermosphere. The overall flow morphology and altitude distribution of ENAs, solar wind H+ (SWH+), and ionospheric O+ imply that SWH
Dipolarization fronts as a consequence of transient reconnection: In situ evidence
André, M.; Hamrin, M.; Sitnov, M. I. +10 more
Dipolarization fronts (DFs) are frequently detected in the Earth's magnetotail from XGSM = -30 RE to XGSM = -7 RE. How these DFs are formed is still poorly understood. Three possible mechanisms have been suggested in previous simulations: (1) jet braking, (2) transient reconnection, and (3) spontaneous f…
Spontaneous formation of dipolarization fronts and reconnection onset in the magnetotail
Merkin, V. G.; Sitnov, M. I.; Moore, T. E. +2 more
We present full-particle simulations of 2-D magnetotail current sheet equilibria with open boundaries and zero driving. The simulations show that spontaneous formation of dipolarization fronts and subsequent formation of magnetic islands are possible in equilibria with an accumulation of magnetic flux at the tailward end of a sufficiently thin cur…
Bursty magnetic reconnection at Saturn's magnetopause
Coates, A. J.; Dougherty, M. K.; Hasegawa, H. +6 more
We infer the evolution of magnetopause reconnection from simultaneous in situ magnetopause crossings and auroral observations by Cassini on 19 July 2008. Depending on the magnetosheath field, it proceeds from (i) the high-latitude lobe, producing a cusp spot in the aurora, to (ii) lower latitude but north of Cassini, evidenced by an enhancement of…
Magnetic topologies of an in vivo FTE observed by Double Star/TC-1 at Earth's magnetopause
Dunlop, M.; Raeder, J.; Zhong, J. +5 more
transfer events (FTEs) are magnetic flux ropes formed at planetary magnetopauses (MPs). Although evidence suggests that FTEs form through time-dependent magnetic reconnection, details of that process and 3D structure of the flux ropes remain largely unclear. This letter presents Double Star/TC-1 data of an FTE occurred on 7 April 2004 which show t…
Solar cycle effects on the ion escape from Mars
Barabash, S.; Lundin, R.; Holmström, M. +6 more
Solar cycle effects on the escape of planetary ions from Mars are investigated using Mars Express Analyzer of Space Plasmas and Energetic Atoms 3 data from June 2007 to January 2013. Average and median tail fluxes of low-energy (<300 eV) heavy ions (O+, O2+), derived from the full data set covering 7900 orbits, …
Cassini CAPS-ELS observations of negative ions in Titan's ionosphere: Trends of density with altitude
Lewis, G. R.; Coates, A. J.; Jones, G. H. +2 more
Observations with the Electron Spectrometer sensor of the Cassini Plasma Spectrometer (CAPS-ELS) have revealed the existence of negative ions in Titan's ionosphere. Negative ions are observed during encounters whenever the instrument points in the ram direction at altitudes 950-1400 km. Complex hydrocarbon and nitrile chemical processes are believ…
Mapping HF waves in the reconnection diffusion region
Pickett, J. S.; André, M.; Vaivads, A. +2 more
We study in detail high-frequency (HF) plasma waves between the electron cyclotron and plasma frequencies within a reconnection diffusion region (DR) encountered by Cluster in the magnetotail using continuous electric field waveforms. We identify three wave types, all observed within the separatrix regions: Langmuir waves (LW), electrostatic solit…