Search Publications
Methanol on Enceladus
Hodyss, Robert; Goguen, Jay D.; Yung, Yuk L. +4 more
Near infrared spectra of the surface of Enceladus returned by Cassini show the presence of an absorption feature at 3.53 µm, ascribed by Brown et al. (2006) to “short chain organics,” and by Newman et al. (2007) to hydrogen peroxide. We assign this feature tentatively to methanol. Variations in the peak position of the feature suggest that m…
Tracing solar wind plasma entry into the magnetosphere using ion-to-electron temperature ratio
Berchem, J.; Escoubet, C. P.; Dandouras, I. +22 more
When the solar wind Mach number is low, typically such as in magnetic clouds, the physics of the bow shock leads to a downstream ion-to-electron temperature ratio that can be notably lower than usual. We utilize this property to trace solar wind plasma entry into the magnetosphere by use of Cluster measurements in the vicinity of the dusk magnetop…
Plasma environment at Titan's orbit with Titan present and absent
Coates, A. J.; Russell, C. T.; Wei, H. Y. +2 more
To understand the possible large scale influence of Titan on its plasma environment, we study the magnetic fields and plasma measurements, both when Cassini flies close to Titan and when Cassini crosses the moon's orbit far from it. Using 98 Cassini passes from 06/2004 to 12/2008, we examine the plasma environments at the orbit of Titan with the m…
Hydrogen in the extended Venus exosphere
Zhang, T. L.; Volwerk, M.; Bertaux, J. L. +4 more
The nearly absence of water in the atmosphere of Venus is a major difference to the situation at Earth. The actual content of hydrogen in the exosphere is still an open issue, since no in situ measurements are available yet. A different method uses the presence of proton cyclotron waves as an early tracer of ionized planetary hydrogen picked-up by…
Rotation period of Jupiter from the observation of its magnetic field
Russell, C. T.; Yu, Z. J.
To determine the Jovian internal rotation rate, historically one has used the repetition period (periodicity) of decametric and decimetric radio waves. The period with which decametric and decimetric radio waves recur on Jupiter (the System III period) was defined by the IAU in 1965 to be 9h 55m 29.71s, based on early radio astronomical data. A mo…
A magnetospheric generator driving ion and electron acceleration and electric currents in a discrete auroral arc observed by Cluster and DMSP
Roth, M.; De Keyser, J.; Maggiolo, R. +1 more
Simultaneous observations on April 28, 2001 by Cluster and DMSP-F14 reveal a stable discrete auroral arc and fluxes of field-aligned accelerated electrons and ions coincident with a magnetospheric plasma interface at an altitude of 4.5 RE in the dusk sector. We compare satellite data with a quasi-stationary magnetosphere-ionosphere coup…
Association of phyllosilicates and the inverted channel in Miyamoto crater, Mars
Wiseman, S. M.; McGuire, P. C.; Marzo, G. A. +4 more
The western floor of the Miyamoto crater in Sinus Meridiani on Mars exhibits both geomorphic and spectral evidence for aqueous history. It contains a sinuous and narrow ridge that is interpreted to be an inverted channel and is suggestive of past fluvial activity. Phyllosilicates occur in materials that are proximal to the paleochannel, but are no…
Thermal phase curves observed in Saturn's main rings by Cassini-CIRS: Detection of an opposition effect?
Altobelli, N.; Flandes, A.; Leyrat, C. +4 more
We report on thermal phase curve measurements of Saturn's main rings by the CIRS infrared spectrometer on-board the CASSINI spacecraft. The extensive data set acquired by Cassini since its insertion in orbit around Saturn provides for the first time spatially resolved temperature measurements over broad phase angle ranges and for different solar e…
Magnetosheath fluctuations at Venus for two extreme orientations of the interplanetary magnetic field
Zhang, T. L.; Wang, C.; Baumjohann, W. +3 more
Using the magnetosheath crossings of Venus Express on two consecutive days, we investigate magnetic fluctuations in the same locations for two extreme interplanetary magnetic field orientations, i.e., nearly along and nearly perpendicular to the solar wind flow. It is shown that the properties of the fluctuations are drastically different at basic…
Radial and latitudinal gradients of anomalous cosmic ray oxygen in the inner heliosphere
Mewaldt, R. A.; Cummings, A. C.; Marsden, R. G. +2 more
We use data from the Ulysses, Advanced Composition Explorer, and Solar Terrestrial Relations Observatory spacecraft to determine the radial and latitudinal gradients of anomalous cosmic ray oxygen in two energy ranges from 4.5-15.6 MeV/nuc in the inner heliosphere for the first time during an A<0 part of the solar cycle. Using measurements from…