Search Publications
Photometric analysis of 1 Ceres and surface mapping from HST observations
Parker, Joel Wm.; Stern, S. Alan; Russell, Christopher T. +5 more
The highest resolution (pixel scale 30 km) images of Ceres to date have been acquired by the Advanced Camera for Surveys onboard Hubble Space Telescope, through three wide band filters, centered at 535, 335, and 223 nm, covering more than one rotation of Ceres. The lightcurve at 535 nm agrees with earlier observations at V-band [Tedesco, E.F., Tay…
Europa's atmosphere, gas tori, and magnetospheric implications
Smyth, William H.; Marconi, Max L.
A two-dimensional kinetic model calculation for the water group species (H 2O, H 2, O 2, OH, O, H) in Europa's atmosphere is undertaken to determine its basic compositional structure, gas escape rates, and velocity distribution information to initialize neutral cloud model calculations for the most important gas to…
Compositional and physical results for Rosetta's new target Comet 67P/Churyumov Gerasimenko from narrowband photometry and imaging
Schleicher, David G.
We present compositional and physical results of Comet 67P/Churyumov-Gerasimenko, the new target of ESA's Rosetta mission. A total of 16 nights of narrowband photometry were obtained at Lowell Observatory during the 1982/83 and 1995/96 apparitions, along with one night of imaging near perihelion in 1996. These data encompass an interval of -61 to …
Near-infrared spectra of the leading and trailing hemispheres of Enceladus
Smith, J. D.; Verbiscer, Anne J.; Skrutskie, Michael F. +5 more
We present individual spectra 0.8-2.5 µm of the leading and trailing hemispheres of Enceladus obtained with the CorMASS spectrograph on the 1.8 m Vatican Advanced Technology Telescope (VATT) at the Mount Graham International Observatory. While the absorption bands of water ice dominate the spectrum of both hemispheres, most of these bands ar…
On the orbits and masses of the satellites of the Pluto Charon system
Lee, Man Hoi; Peale, S. J.
Two small satellites of Pluto, S/2005 P1 (hereafter P1) and S/2005 P2 (hereafter P2), have recently been discovered outside the orbit of Charon, and their orbits are nearly circular and nearly coplanar with that of Charon. Because the mass ratio of Charon-Pluto is ∼0.1, the orbits of P2 and P1 are significantly non-Keplerian even if P2 and P1 have…
A strong vortex in Saturn's South Pole
Hueso, R.; Sánchez-Lavega, A.; Rojas, J. F. +1 more
Saturn's southern pole was observed at high resolution by the Cassini Imaging Science Subsystem (ISS) during the spacecraft insertion orbit in July 2004. Cloud tracking of individual features on images taken at a wavelength of 938 nm reveal the existence of a strong polar vortex enclosed by a jet with maximum speed of 160±10 ms relative to System …
Ozone abundance on Mars from infrared heterodyne spectra. I. Acquisition, retrieval, and anticorrelation with water vapor
A'Hearn, Michael F.; Sonnabend, Guido; Hewagama, Tilak +8 more
Observations of ozone on Mars were made using the Goddard Space Flight Center's Infrared Heterodyne Spectrometer and Heterodyne Instrument for Planetary Wind and Composition at the NASA Infrared Telescope Facility. Ozone is an important observable tracer of martian photochemistry. Infrared heterodyne spectroscopy with spectral resolution ⩾10 is th…
On the vertical wind shear of Saturn's Equatorial Jet at cloud level
Sánchez-Lavega, A.; Pérez-Hoyos, S.
In this work we analyze and compare the vertical cloud structure of Saturn's Equatorial Zone in two different epochs: the first one close to the Voyagers flybys (1979-1981) and the second one in 2004, when the Cassini spacecraft entered its orbit around the planet. Our goal is to retrieve the altitude of cloud features used as zonal wind tracers i…
Latitudinal variation of Saturn photochemistry deduced from spatially-resolved ultraviolet spectra
Fouchet, Thierry; Connerney, J. E. P.; Prangé, Renée +2 more
We obtained spatially-resolved ultraviolet spectra of Saturn in 1994 with the Faint Object Spectrometer and Goddard High Resolution Spectrograph of the Hubble Space Telescope. We observed four areas on the planet at 15° N, 33° S, 41° S, and 52° S, with a field-of-view of less than 2 × 2 arcsec 2, compared to the 16-arcsec planet diamete…
Discovery of a binary Centaur
Noll, Keith S.; Levison, Harold F.; Stephens, Denise C. +1 more
We have identified a binary companion to (42355) 2002 CR 46 in our ongoing deep survey using the Hubble Space Telescope's High Resolution Camera. It is the first companion to be found around an object in a non-resonant orbit that crosses the orbits of giant planets. Objects in orbits of this kind, the Centaurs, have experienced repeated…