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Current state of modeling the photochemistry of Titan's mutually dependent atmosphere and ionosphere
[1] In the context of recent observations, microphysical models, and laboratory data, a photochemical model of Titan’s atmosphere, including updated chemistry focusing on rate coefficients and crossExpand
The abundances of constituents of Titan's atmosphere from the GCMS instrument on the Huygens probe
Direct atmospheric measurements from the Gas Chromatograph Mass Spectrometer (GCMS), including altitude profiles of the constituents, isotopic ratios and trace species (including organic compounds), were reported, confirming the primary constituents were confirmed to be nitrogen and methane. Expand
Detection of Methane in the Atmosphere of Mars
We report a detection of methane in the martian atmosphere by the Planetary Fourier Spectrometer onboard the Mars Express spacecraft. The global average methane mixing ratio is found to be 10 ± 5Expand
The composition of the Jovian atmosphere as determined by the Galileo probe mass spectrometer.
Analysis of some of the constituents detected suggests that icy planetesimals made significant contributions to the volatile inventory, and (4) a moderate decrease in D/H but no detectable change in (D + 3He)/H in this part of the galaxy during the past 4.6 Gyr. Expand
Composition of Titan's lower atmosphere and simple surface volatiles as measured by the Cassini‐Huygens probe gas chromatograph mass spectrometer experiment
[1] The Cassini-Huygens probe gas chromatograph mass spectrometer (GCMS) determined the composition of the Titan atmosphere from ∼140 km altitude to the surface. After landing, it returnedExpand
Updated Galileo probe mass spectrometer measurements of carbon, oxygen, nitrogen, and sulfur on Jupiter
The in situ measurements of the Galileo Probe Mass Spectrometer (GPMS) were expected to constrain the abundances of the cloudforming condensible volatile gases: H2O, H2S, and NH3. However, since theExpand
Book-Review - Atmospheres and Ionospheres of the Outer Planets and Their Satellites
One of the most fundamental discoveries of the solar system was the detection of four moons in orbit around Jupiter by Galileo Galilei in 1610. The discovery was significant not only in the contextExpand
A comparison of the atmospheres of Jupiter and Saturn: deep atmospheric composition, cloud structure, vertical mixing, and origin.
The current understanding of the composition, vertical mixing, cloud structure and the origin of the atmospheres of Jupiter and Saturn is presented and a much more vigorous vertical mixing in Saturn's middle-upper atmosphere than in Jupiter's is pointed to. Expand
Galileo Probe Measurements of D/H and 3He/4He in Jupiter's Atmosphere
The Galileo Probe Mass Spectrometer measurements in the atmosphere of Jupiter give D/H = (2.6 ± 0.7) × 10-5 3He/4He = (1.66 ± 0.05) × 10-4These ratios supercede earlier results by Niemann et al.Expand
A low-temperature origin for the planetesimals that formed Jupiter
It is shown that argon, krypton and xenon in Jupiter's atmosphere are enriched to the same extent as the other heavy elements, which suggests that the planetesimals carrying these elements must have formed at temperatures lower than predicted by present models of giant-planet formation. Expand