Search Publications
Discrete cloud activity in Saturn's equator during 1995, 1996 and 1997
Rojas, J. F.; Colas, F.; Lecacheux, J. +2 more
A regular extensive CCD imaging of Saturn allowed us to analyze the discrete cloud activity in the Equatorial Zone from 1995 to 1997. The large-scale storm observed in 1994 at +10° ( Sanchez-Lavega et al., 1994, 1996) was rediscovered in 1995, reaching a lifetime >1 year. Its slow motion characterized by a zonal velocity difference of -150 ms <…
The Raman signature of H2 in the uv spectra of Uranus and Neptune: Constraints on the haze optical properties and on the para-H2 fraction
Courtin, Régis
The geometric albedos of Uranus and Neptune, inferred from archived Hubble Space Telescope observations and from the ground-based measurements of Karkoschka, 1994, are modeled in the wavelength range 2200-4200 Å. The radiative transfer model, which includes Rayleigh-Raman scattering and Mie scattering by haze particles, aims at reproducing the fin…
A flux enhancement measured in energetic particles(E ∼ 60-100 keV) by the epona instrument aboard Giotto close to P⧸Grigg-Skjellerup, and its interpretationas the signature of a companion comet
McKenna-Lawlor, Susan M. P.; Afonin, Valerie V.
A significant flux enhancement in energetic particles (E ∼ 60-⩾260 keV),showing internal fine structure interpreted to represent signatures produced during the traversalof various cometary boundaries in P⧸Grigg-Skjellerup, was recorded by the EPONA instrumentaboard spacecraft Giotto on 10 July 1992. A further internally structured flux enhancement…
Lyman-alpha observations of comet Hyakutake with SWAN on SOHO
Schmidt, W.; Bertaux, J. L.; Lallement, R. +7 more
The SWAN instrument on board SOHO is a Lyman-α (Lα) photometer able to map the sky intensity with a resolution of 1°, and a capability of microstepping (0.1°). SWAN is primarily devoted to the study of the large scale distribution of solar wind from its imprints on the interplanetary sky background, but was in addition extensively used to map the …
Cassini uvis observations of Saturns rings
Colwell, Joshua E.; Esposito, Larry W.; McClintock, William E.
The Cassini Ultra-violet Imaging Spectrograph (UVIS) is part of the remote sensing payload of the Cassini Orbiter spacecraft. Its science objectives include investigation of the chemistry, clouds, and energy balance of the Titan and Saturn atmospheres ; neutrals in the magnetosphere ; D/H ratio for Titan and Saturn ; and structure and evolution of…
Correspondence between field aligned currents observed by Ulysses and HST auroral emission
Dougherty, M. K.; Dunlop, M. W.; Prange, R. +1 more
Auroral emission is direct evidence for the magnetophere/ionosphere coupling which exists for a magnetised planet such as Jupiter. This coupling takes place by way of momentum transfer which occurs via field aligned currents. The driving mechanism for the auroral emission is charged particle precipitation along the field lines. During the Ulysses …
Cassini as a heliospheric probe - the potential of pick-up ion measurements during its cruise phase
Fichtner, H.; Mall, U.; Hamilton, D. C. +2 more
Measurements of the spatial distributions of pick-up ions can be utilized to infer important information about the structure of the heliosphere. First, a determination of the symmetry axis of flux distributions of pick-up ions not experiencing any significant filtration of their neutral parent atoms in the heliospheric interface represents a new m…
Ulysses observations of field-perpendicular plasma flows in the Jovian magnetosphere: comparison of ExB velocity vectors derived from energetic ion and thermal electron data
Balogh, A.; McComas, D. J.; Dunlop, M. W. +4 more
The ExB velocity vectors which correspond to the field-perpendicular flow of the low-energy plasma have been independently derived for the Ulysses flyby of Jupiter using energetic ion and thermal electron data. In this paper these measurements are compared. It is shown that reasonable quantitative agreement exists during the prenoon inbound pass, …
Imaging Saturns dust rings using energetic neutral atoms
Krimigis, S. M.; Mitchell, D. G.; Roelof, E. C. +3 more
The intense populations of magnetically trap- ped, energetic charged particles that constitute the radiation belts of Saturn's inner magnetosphere are slowly transported towards the planet by radial diffusion processes. Many of these energetic particles interact with the rings of Saturn and ultimately are lost to the magnetospheric system. Energet…
The Cassini-Huygens SSP refractometer : ref
Geake, J. E.; Mill, C. S.
The refractometer (REF) in the Huygens probe Surface Science Package (SSP) is a linear critical-angle refractometer ; it covers the refractive index range 1.2500-1.4500 with a discrimination of 0.0005, giving an accuracy of about 0.5% in the relative abundance of methane and ethane in the expected mixture on the possibly liquid surface of Titan. L…