The deep composition of Uranus and Neptune from in situ exploration and thermochemical modeling

Abstract

The distant ice giants of the Solar System, Uranus and Neptune, have only been visited by one space mission, Voyager 2. The current knowledge on their composition remains very limited despite some recent advances. A better characterization of their composition is however essential to constrain their formation and evolution, as a significant fraction of their mass is made of heavy elements, contrary to the gas giants Jupiter and Saturn. An in situ probe like Galileo would provide us with invaluable direct ground-truth composition measurements. However, some of the condensibles will remain out of the grasp of a shallow probe. While additional constraints could be obtained from a complementary orbiter, thermochemistry and diffusion modeling can further help us to increase the science return of an in situ probe.

Accepted for publication in Space Science Reviews

References in corpus (42)

• The James Webb Space Telescope
• Ab initio Equation of State data for hydrogen, helium, and water and the internal structure of Jupiter
• A chemical model for the atmosphere of hot Jupiters
• The elemental composition of the Sun I. The intermediate mass elements Na to Ca
• VULCAN: an Open-Source, Validated Chemical Kinetics Python Code for Exoplanetary Atmospheres
• The elemental composition of the Sun III. The heavy elements Cu to Th
• A new equation of state for dense hydrogen-helium mixtures
• The Effects of Consistent Chemical Kinetics Calculations on the Pressure-Temperature Profiles and Emission Spectra of Hot Jupiters
• Ab initio equations of state for hydrogen (H-REOS.3) and helium (He-REOS.3) and their implications for the interior of Brown Dwarfs
• The water abundance in Jupiter's equatorial zone
• Condensation-inhibited convection in hydrogen-rich atmospheres: Stability against double-diffusive processes and thermal profiles for Jupiter, Saturn, Uranus, and Neptune
• Excess C/O and C/H in outer protoplanetary disk gas
• Methane on Uranus: The case for a compact CH4 cloud layer at low latitudes and a severe CH4 depletion at high-latitudes based on re-analysis of Voyager occultation measurements and STIS spectroscopy
• Jupiter internal structure: the effect of different equations of state
• The solar silicon abundance based on 3D non-LTE calculations
• Dust Ablation on the Giant Planets: Consequences for Stratospheric Photochemistry
• Neptune's Atmospheric Composition from AKARI Infrared Spectroscopy
• Deep Atmosphere Composition, Structure, Origin, and Exploration, with Particular Focus on Critical in situ Science at the Icy Giants
• Methane depletion in both polar regions of Uranus inferred from HST/STIS and Keck/NIRC2 observations
• Probable detection of hydrogen sulphide (H${}_2$S) in Neptune's atmosphere
• The Formation of Uranus & Neptune: Challenges and Implications For Intermediate-Mass Exoplanets
• Constraining the Origins of Neptune's Carbon Monoxide Abundance with CARMA Millimeter-wave Observations
• Mid-Infrared Spectroscopy of Uranus from the Spitzer Infrared Spectrometer: 2. Determination of the Mean Composition of the Upper Troposphere and Stratosphere
• Measuring Jupiter's water abundance by Juno: the link between interior and formation models
• Scientific rationale of Saturn's in situ exploration
• Jupiter's Ammonia Distribution Derived from VLA Maps at 3--37 GHz
• A new chemical scheme for giant planet thermochemistry. Update of the methanol chemistry and new reduced chemical scheme
• The Origin of Nitrogen on Jupiter and Saturn from the ${}^{15}$N/${}^{14}$N Ratio
• Thermochemistry and vertical mixing in the tropospheres of Uranus and Neptune: How convection inhibition can affect the derivation of deep oxygen abundances
• 3D non-LTE line formation of neutral carbon in the Sun
• Jupiter's formation in the vicinity of the amorphous ice snowline
• The measured compositions of Uranus and Neptune from their formation on the CO iceline
• Latitudinal variation in the abundance of methane (CH4) above the clouds in Neptune's atmosphere from VLT/MUSE Narrow Field Mode Observations
• New Insights on Jupiter's Deep Water Abundance from Disequilibrium Species
• A reduced chemical scheme for modelling warm to hot hydrogen-dominated atmospheres
• Neptune's Latitudinal Variations as Viewed with ALMA
• 2D photochemical modeling of Saturn's stratosphere. Part I: Seasonal variation of atmospheric composition without meridional transport
• New insights on Saturn's formation from its nitrogen isotopic composition
• The Formation of Uranus and Neptune: Fine Tuning in Core Accretion
• 1D photochemical model of the ionosphere and the stratosphere of Neptune
• Key Atmospheric Signatures for Identifying the Source Reservoirs of Volatiles in Uranus and Neptune
• Chemical and Isotopic Composition Measurements on Atmospheric Probes Exploring Uranus and Neptune

Cited by in corpus (8)

• Astrochemistry and compositions of planetary systems
• A warm Neptune's methane reveals core mass and vigorous atmospheric mixing
• Atmospheric chemistry on Uranus and Neptune
• A 3D picture of moist-convection inhibition in hydrogen-rich atmospheres: Implications for K2-18 b
• A subsolar oxygen abundance or a radiative region deep in Jupiter revealed by thermochemical modelling
• Chemical and Isotopic Composition Measurements on Atmospheric Probes Exploring Uranus and Neptune
• The deep oxygen abundance in Solar System Giant Planets, with a new derivation for Saturn
• Planetary Exploration Horizon 2061 Report, Chapter 4: From planetary exploration goals to technology requirements