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Kelvin-Helmholtz waves under southward interplanetary magnetic field
Sahraoui, F.; Parks, G. K.; Goldstein, M. L. +3 more
The Kelvin-Helmholtz waves have been observed along the Earth's low-latitude magnetopause and have been suggested to play a certain role in the entry of solar wind plasma into Earth's magnetosphere. In situ observations of the KH waves (KHW) and, in particular, a nonlinear stage of the KH instability, i.e., rolled-up KH vortices (KHVs), have been …
Solar extreme ultraviolet irradiance: Present, past, and future
Meier, R. R.; Lean, J. L.; Evans, J. S. +4 more
New models of solar extreme ultraviolet (EUV) irradiance variability are constructed in 1 nm bins from 0 to 120 nm using multiple regression of the Mg II and F10.7 solar activity indices with irradiance observations made during the descending phase of cycle 23. The models have been used to reconstruct EUV spectra daily since 1950, annua…
A THEMIS survey of flux ropes and traveling compression regions: Location of the near-Earth reconnection site during solar minimum
Imber, S. M.; Angelopoulos, V.; Slavin, J. A. +1 more
A statistical study of flux ropes and traveling compression regions (TCRs) during the Time History of Events and Macroscale Interactions during Substorms second tail season has been performed. A combined total of 135 flux ropes and TCRs in the range GSM X ∼ -14 to -31 RE were identified, many of these occurring in series of two or more …
Periodic motion of Saturn's nightside plasma sheet
André, N.; Coates, A. J.; Russell, C. T. +9 more
Saturn's magnetosphere is replete with magnetospheric periodicities; magnetic fields, plasma parameters, energetic particle fluxes, and radio emissions have all been observed to vary at a period close to that of Saturn's assumed sidereal rotation rate. In particular, periodicities in Saturn's magnetotail can be interpreted in terms of periodic ver…
Cluster observations of multiple dipolarization fronts
Pickett, J. S.; Goldstein, M. L.; Lee, E. +1 more
We present Cluster observations of a series of dipolarization fronts (DF 1 to 6) at the central current sheet in Earth's magnetotail. The velocities of fast earthward flow following behind each DF 1-3 are comparable to the Alfvén velocity, indicating that the flow bursts might have been generated by bursty reconnection that occurred tailward of th…
The distribution of solar wind speeds during solar minimum: Calibration for numerical solar wind modeling constraints on the source of the slow solar wind
Arge, C. N.; Odstrcil, D.; Owens, M. J. +2 more
It took the solar polar passage of Ulysses in the early 1990s to establish the global structure of the solar wind speed during solar minimum. However, it remains unclear if the solar wind is composed of two distinct populations of solar wind from different sources (e.g., closed loops which open up to produce the slow solar wind) or if the fast and…
Embedded current sheets in the Earth’s magnetotail
Malova, H. V.; Petrukovich, A. A.; Zelenyi, L. M. +3 more
In this investigation we introduce and discuss quantitative parameters of a thin current sheet embedded in the background plasma sheet. We use Cluster statistics and empirical models, as well as self-consistent simulations, to understand the formation and development of embedded current sheets, in particular in the course of substorms. Data and th…
Antiparallel and component reconnection at the dayside magnetopause
Fuselier, S. A.; Trattner, K. J.; Petrinec, S. M.
Two types of reconnection occur at the Earth's magnetopause: component and antiparallel reconnection. Recently, an empirical model was developed that purportedly determines under what solar wind conditions one or the other type of reconnection is dominant. This empirical model is tested using observations at the magnetopause from the Cluster space…
Modeling Mars' ionosphere with constraints from same-day observations by Mars Global Surveyor and Mars Express
Tellmann, Silvia; Pätzold, Martin; Withers, Paul +3 more
We have analyzed a brief period of same-day observations of the Martian ionosphere using data obtained in December 2004 from the Mars Global Surveyor (MGS) and Mars Express (MEX) radio occultation experiments. These data were taken shortly after sunrise under solstice conditions in both hemispheres, with MGS in the summer (northern) hemisphere at …
Bifurcations of the main auroral ring at Saturn: ionospheric signatures of consecutive reconnection events at the magnetopause
Milan, S. E.; Bonfond, B.; Gérard, J. -C. +4 more
This work reports for the first time on bifurcations of the main auroral ring at Saturn observed with the UVIS instrument onboard Cassini. The observation sequence starts with an intensification on the main oval, close to noon, which is possibly associated with dayside reconnection. Consecutive bifurcations appear with the onset of dayside reconne…