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In this work, a new equation of state for a H 2 –He–H 2 O–CH 4 mixture is presented. The equation is optimized for the deep jovian atmosphere (∼100bars) where the NASA Juno Microwave Radiometer (MWR) will probe. The methodology used is based upon that of Lemmon and Jacobsen (Lemmon, E.W., Jacobsen, R.T. [2004]. J. Phys. Chem. Ref. Data 33, 593–+) and Kunz et al. (Kunz, O.,...
The line intensities of the fundamental rotational transitions of H 13 CN and HC 15 N were observed towards two prestellar cores, L183 and L1544, and lead to molecular isotopic ratios 140⩽ 14 N/ 15 N⩽250 and 140⩽ 14 N/ 15 N⩽360, respectively. The range of values reflect genuine spatial variations within the cores. A comprehensive analysis of the available...
We report the history of the first recorded ground-based radio detection of Saturn’s lightning using the Ukrainian UTR-2 radiotelescope at frequencies from 20 to 25MHz. The observations were performed between 29 January and 3 February 2006, during which lighting activity (E-storm) on Saturn was detected by the radio experiment onboard Cassini spacecraft. The minimum detectable flux density (1σ-level)...
This work focuses on determining the latitudinal structure of ammonia vapor in Saturn’s cloud layer near 1.5 bars using the brightness temperature maps derived from the Cassini RADAR (Elachi et al. [2004], Space Sci. Rev. 115, 71–110) instrument, which works in a passive mode to measure thermal emission from Saturn at 2.2-cm wavelength. We perform an analysis of five brightness temperature maps that...
We present well-calibrated, high-resolution maps of Saturn’s thermal emission at 2.2-cm wavelength obtained by the Cassini RADAR radiometer through the Prime and Equinox Cassini missions, a period covering approximately 6years. The absolute brightness temperature calibration of 2% achieved is more than twice better than for all previous microwave observations reported for Saturn, and the spatial resolution...
We present maps of Neptune in and near the CO (2–1) rotation line at 230.538GHz. These data, taken with the Combined Array for Research in Millimeter-wave Astronomy (CARMA) represent the first published spatially-resolved maps in the millimeter. At large (∼5GHz) offsets from the CO line center, the majority of the emission originates from depths of 1.1–4.7bar. We observe a latitudinal gradient in...
Thermophysical models consistent with Earth’s Moon and infrared and submillimeter measurements obtained during the Rosetta fly-by of Asteroid (21) Lutetia have been applied to computations of thermal fluxes from Asteroids (4) Vesta, (1) Ceres, (2) Pallas, and (10) Hygiea. Comparisons are made with Earth- and space-based flux measurements that cover the infrared-to-centimeter wavelength spectrum. The...
We use the specific scintillations of jovian decametric radio sources (modulation lanes), which are produced by plasma inhomogeneities in the vicinity of that planet, to probe the inner magnetosphere of Jupiter. The positions and frequency drift of 1762 lanes have been measured on the DAM spectra from archives. A special 3D algorithm is used for space localization of field-aligned magnetospheric inhomogeneities...
Comet 103P/Hartley 2 made a close approach to the Earth in October 2010. It was the target of an extensive observing campaign including ground- and orbit-based observatories and was visited by the Deep Impact spacecraft in the framework of its mission extension EPOXI. We present observations of HCN and CH 3 OH emission lines conducted with the IRAM Plateau de Bure interferometer on 22–23,...
A new model for the complex dielectric constant of aqueous ammonia (NH 4 OH) under conditions characteristic of the jovian clouds has been developed. The new model is based on laboratory measurements in the frequency range between 2 and 8.5GHz for ammonia concentrations of 0–8.5% by volume and temperatures between 274 and 297K. The new model is based on the Meissner and Wentz (Meissner, T...
We present an electromagnetic model that relates the microwave backscatter and thermal emission from linear dune fields to their compositional, physical (roughness, subsurface porosity/heterogeneity) and geometrical (slope, orientation) properties. This model shows the value of exploring these highly directional and geometrical features in light of both their backscattering cross-section and emissivity...
The global distribution of atmospheric pressure retrieved from Cassini radio occultations is reanalyzed and interpreted in a meteorological context. The retrieval of Titan’s atmospheric pressure profile from radio occultations is ambiguous because it depends on the methane mole fraction, which is not precisely known in the troposphere beyond the entry site of the Huygens Probe. The surface pressure...
We present a radar map of the Titan’s seas, with bathymetry estimated as proportional to distance from the nearest shore. This naïve analytic bathymetry, scaled to a recent radar sounding of Ligeia Mare, suggests a total liquid volume of ∼32,000km 3 , at the low end of estimates made in 2008 when mapping coverage was incomplete. We note that Kraken Mare has two principal basins, separated...
We observed Neptune between June and October 2003 at near- and mid-infrared wavelengths with the 10-m W.M. Keck II and I telescopes, respectively; and at radio wavelengths with the Very Large Array. Images were obtained at near-infrared wavelengths with NIRC2 coupled to the adaptive optics system in both broad- and narrow-band filters between 1.2 and 2.2μm. In the mid-infrared we imaged Neptune at...
We present sub-millimeter observations of the ground-state rotational transition (1 10 –1 01 ) of water vapor from Comet C/2002 T7 (LINEAR) obtained with the MIRO instrument on the ESA Rosetta spacecraft (s/c) orbiter on April 30, 2004. At the time of the observations, the comet was at a distance of 0.63AU from the Sun, 0.68AU from the MIRO telescope, and about 7.5days after its perihelion...
Since its arrival at Saturn, the Cassini spacecraft has had only a few opportunities to observe Iapetus, Saturn’s most distant regular satellite. These observations were all made from long ranges (>100,000km) except on September 10, 2007, during Cassini orbit 49, when the spacecraft encountered the two-toned moon during its closest flyby so far. In this pass it collected spatially resolved data...
In the past two decades, multiple observations of Venus have been made at X-Band (3.6cm) using the Jansky Very Large Array (VLA), and maps have been created of the 3.6cm emission from Venus (see, e.g., Devaraj, K. [2011]. The Centimeter- and Millimeter-Wavelength Ammonia Absorption Spectra under Jovian Conditions. PhD Thesis, Georgia Institute of Technology, Atlanta, GA). Since the emission morphology...
We report the electron density in a plasma tail of Comet ISON (C/2012 S1) derived from interplanetary scintillation (IPS) observations during November 1–28, 2013. Comet ISON showed a well-developed plasma tail (longer than 2.98×107km) before its perihelion passage on November 28. We identified a radio source whose line-of-sight approached the ISON’s plasma tail in the above period and obtained its...
Doppler shifts of sub-millimeter 12CO (346GHz) and 13CO (330GHz) and millimeter 12CO (230GHz) line absorptions were mapped around the circum-disk terminator of Venus before, during, and after the June 5, 2012 solar transit, employing the James Clerk Maxwell Telescope (JCMT). Radiative transfer analysis of the solar transit 12CO thermal line absorptions yields cross-terminator winds in the Venus lower...
Over 130 laboratory measurements of the 2–4mm wavelength opacity of sulfur dioxide in a carbon dioxide atmosphere under simulated conditions for the upper Venus troposphere (temperatures between 308 and 343K and pressures between 0.03 and 2bar) have been made. These measurements along with the centimeter wavelength measurements by Steffes et al. (Steffes, P.G. et al. [2015]. Icarus 245, 153–161) have...
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