Search Publications
Deep Impact, Stardust-NExT and the behavior of Comet 9P/Tempel 1 from 1997 to 2010
A'Hearn, M. F.; Vincent, J. -B.; Bhatt, B. C. +55 more
We present observational data for Comet 9P/Tempel 1 taken from 1997 through 2010 in an international collaboration in support of the Deep Impact and Stardust-NExT missions. The data were obtained to characterize the nucleus prior to the Deep Impact 2005 encounter, and to enable us to understand the rotation state in order to make a time of arrival…
Non-LTE radiative transfer for sub-millimeter water lines in Comet 67P/Churyumov-Gerasimenko
Kamp, Lucas; Gulkis, Samuel; Lee, Seungwon +2 more
The European Space Agency (ESA) Rosetta spacecraft (Schulz, R., Alexander, C., Boehnhardt, H., Glassmeier, K.H. (Eds.) [2009]. "ROSETTA - ESA") will encounter Comet 67P/Churyumov-Gerasimenko in 2014 and spend the next 18 months in the vicinity of the comet, permitting very high spatial and spectral resolution observations of the coma and nucleus. …
Scattering particles in nightside limb observations of Venus’ upper atmosphere by Venus Express VIRTIS
Irwin, P. G. J.; Drossart, P.; Piccioni, G. +2 more
Nightside infrared limb spectra of the Venus upper atmosphere, obtained by Venus Express VIRTIS, show strong scattering of thermal radiation. This scattering of upward-going radiation into the line-of-sight is dominant below 82.5 km even at a wavelength of 5 µm, which is indicative of relatively large particles. We show that 1 µm-sized…
Improved measurement of Asteroid (4) Vesta’s rotational axis orientation
Russell, Christopher T.; Thomas, Peter C.; Li, Jian-Yang +6 more
We report an improved measurement of the rotational axis orientation of Asteroid (4) Vesta. By analyzing and combining all previous measurements using a limb-fitting technique from ground/HST data collected from 1983 to 2006, we derive a pole solution of (RA = 304.5°, Dec = 41.5°). Images of Vesta acquired with the Wide Field Camera 3 onboard the …
Jovian chromophore characteristics from multispectral HST images
Simon-Miller, Amy A.; Chanover, Nancy J.; Strycker, Paul D. +2 more
The chromophores responsible for coloring the jovian atmosphere are embedded within Jupiter's vertical aerosol structure. Sunlight propagates through this vertical distribution of aerosol particles, whose colors are defined by ϖ0( λ), and we remotely observe the culmination of the radiative transfer as I/ F( λ). In this study, we employ…
Chaos formation by sublimation of volatile-rich substrate: Evidence from Galaxias Chaos, Mars
Head, J. W.; Pedersen, G. B. M.
Galaxias Chaos deviates significantly from other chaotic regions due to the lack of associated outflow channels, lack of big elevation differences between the chaos and the surrounding terrain and due to gradual trough formation. A sequence of troughs in different stages is observed, and examples of closed troughs within blocks suggest that the tr…
An assessment and test of Enceladus as an important source of Saturn’s ring atmosphere and ionosphere
Ip, Wing-Huen; Tseng, Wei-Ling
The existence of an oxygen exosphere and ionosphere in Saturn’s main ring region has been confirmed by the Saturn Orbital Insertion (SOI) observations of the Cassini spacecraft. Through the ion-molecule collisions, the ring atmosphere could serve as a source of O2+ ions throughout Saturn’s magnetosphere. If photolysis of ice in the main rings is t…
SOHO/SWAN observations of comets with small perihelia: C/2002 V1 (NEAT), C/2002 X5 (Kudo-Fujikawa), 2006 P1 (McNaught) and 96P/Machholz 1
Bertaux, J. -L.; Combi, M. R.; Quémerais, E. +4 more
SWAN, the all-sky hydrogen Lyman-alpha camera on the SOHO spacecraft, designed primarily to image the interplanetary neutral hydrogen around the Sun, also observes comets continuously over large portions of their apparitions to the north and south of the ecliptic and at small solar elongation angles. Because of SOHO’s location at the L1 Lagrange p…
Vertical profile of H 2SO 4 vapor at 70-110 km on Venus and some related problems
Krasnopolsky, Vladimir A.
The vertical profile of H 2SO 4 vapor is calculated using current atmospheric and thermodynamic data. The atmospheric data include the H 2O profiles observed at 70-112 km by the SOIR solar occultations, the SPICAV-UV profiles of the haze extinction at 220 nm, the VeRa temperature profiles, and a typical profile of …
Preservation of Late Amazonian Mars ice and water-related deposits in a unique crater environment in Noachis Terra: Age relationships between lobate debris tongues and gullies
Head, James W.; Marchant, David R.; Morgan, Gareth A.
The Amazonian period of Mars has been described as static, cold, and dry. Recent analysis of high-resolution imagery of equatorial and mid-latitude regions has revealed an array of young landforms produced in association with ice and liquid water; because near-surface ice in these regions is currently unstable, these ice-and-water-related landform…