Search Publications
Strong interplanetary field enhancements at Ulysses—evidence of dust trails' interaction with the solar wind?
Balogh, André; Jones, Geraint H.; MacDowall, Robert J. +1 more
Interplanetary field enhancements were first discovered in the vicinity of Venus. These events are characterised by an increase in the magnitude of the heliospheric magnetic field with a near-symmetrical, sometimes thorn-shaped profile, and last from minutes to hours. Surveys of the events near Venus and Earth indicated clustering of the events in…
Mars atmospheric water vapor abundance: 1996-1997
Doose, L. R.; Hunten, D. M.; Sprague, A. L. +1 more
Measurements of martian atmospheric water vapor made throughout Ls = 18.0°-146.4° (October 3, 1996-July 12, 1997) show changes in Mars humidity on hourly, daily, and seasonal time scales. Because our observing program during the 1996-1997 Mars apparition did not include concomitant measurement of nearby CO 2 bands, high north…
Voyager color photometry of Saturn's main rings: a correction
Showalter, Mark R.; Cuzzi, Jeffrey N.; Estrada, Paul R.
We correct a calibration error in our earlier analysis of Voyager color observations of Saturn's main rings at 14° phase angle (Estrada and Cuzzi, 1996, Icarus 122, 251) and present thoroughly revised and reanalyzed radial profiles of the brightness of the main rings in the Voyager green, violet, and ultraviolet filters and the ratios of these bri…
H 2O- and OH-bearing minerals in the martian regolith: . analysis of 1997 observations from HST/NICMOS
Gordon, K. D.; Wolff, M. J.; Noe Dobrea, E. Z. +1 more
We have analyzed observations of the Acidalia hemisphere of Mars taken by the Hubble Space Telescope's Near-Infrared Camera Multi-Object Spectrograph (HST/NICMOS) during July of 1997 ( Ls=152°, northern martian summer). The data consist of images at ∼60 km/pixel resolution, using both narrow- and medium-band filters specifically selecte…
SOHO/LASCO observation of an outburst of Comet 2P/Encke at its 2000 perihelion passage
Lamy, P.; Groussin, O.; Biesecker, D. A.
Comet 2P/Encke was observed with the SOHO/LASCO C2 and C3 coronagraphs over a time interval of 11 days, starting 4 days before its September 2000 perihelion passage and through several broadband visible filters. The lightcurve reveals an outburst which started 4.9 days after perihelion, with the brightness of the coma increasing by 1.5 mag in just…
Cassini-VIMS at Jupiter: solar occultation measurements using Io
Sotin, C.; Brown, R. H.; Baines, K. H. +24 more
We report unusual and somewhat unexpected observations of the jovian satellite Io, showing strong methane absorption bands. These observations were made by the Cassini VIMS experiment during the Jupiter flyby of December/January 2000/2001. The explanation is straightforward: Entering or exiting from Jupiter's shadow during an eclipse, Io is illumi…
HST observation of the atmospheric composition of Jupiter's equatorial region: evidence for tropospheric C 2H 2
Griffith, Caitlin A.; Yelle, Roger V.; Bétrémieux, Yan
This paper presents the first detailed analysis of acetylene absorption features observed longward of 190.0 nm in a jovian spectrum by the Faint Object Spectrograph on board the Hubble Space Telescope. The presence of two features located near 207.0 nm can only be explained by a substantial abundance of acetylene in the upper troposphere. Using a …
An Evolutionary Turbulent Model of Saturn's Subnebula: Implications for the Origin of the Atmosphere of Titan
Mousis, Olivier; Gautier, Daniel; Bockelée-Morvan, Dominique
We have elaborated an evolutionary turbulent model of the subnebula of Saturn derived from that of Dubrulle (1993, Icarus106, 59-76) for the solar nebula, which is valid for a geometrically thin disk. We demonstrate that if carbon and nitrogen were in the form of CO and N 2, respectively, in the early subnebula, these molecules were not…
Photometry of Mercury from SOHO/LASCO and Earth. The Phase Function from 2 to 170 deg.
Howard, Russell A.; Mallama, Anthony; Wang, Dennis
CCD observations of Mercury were obtained with the large angle spectrometric coronograph (LASCO) on the solar and heliospheric observatory spacecraft, near superior and inferior solar conjunctions. Whole disk photometry was extracted from the orange and blue filter images and transformed to V magnitudes on the UBV system. The LASCO data were combi…
The Origin of Water Vapor and Carbon Dioxide in Jupiter's Stratosphere
Lellouch, E.; Encrenaz, T.; Feuchtgruber, H. +6 more
Observations of H 2O rotational lines from the Infrared Space Observatory (ISO) and the Submillimeter Wave Astronomy Satellite (SWAS) and of the CO 2 ν 2 band by ISO are analyzed jointly to determine the origin of water vapor and carbon dioxide in Jupiter's stratosphere. Simultaneous modelling of ISO/LWS and ISO/SW…