Titan's Atmosphere and Climate

Abstract

Titan is the only moon with a substantial atmosphere, the only other thick N${}_2$ atmosphere besides Earth's, the site of extraordinarily complex atmospheric chemistry that far surpasses any other solar system atmosphere, and the only other solar system body with stable liquid currently on its surface. The connection between Titan's surface and atmosphere is also unique in our Solar system; atmospheric chemistry produces materials that are deposited on the surface and subsequently altered by surface-atmosphere interactions such as aeolian and fluvial processes resulting in the formation of extensive dune fields and expansive lakes and seas. Titan's atmosphere is favorable for organic haze formation, which combined with the presence of some oxygen bearing molecules indicates that Titan's atmosphere may produce molecules of prebiotic interest. The combination of organics and liquid, in the form of water in a subsurface ocean and methane/ethane in the surface lakes and seas, means that Titan may be the ideal place in the solar system to test ideas about habitability, prebiotic chemistry, and the ubiquity and diversity of life in the Universe. The Cassini-Huygens mission to the Saturn system has provided a wealth of new information allowing for study of Titan as a complex system. Here I review our current understanding of Titan's atmosphere and climate forged from the powerful combination of Earth-based observations, remote sensing and \emph{in situ} spacecraft measurements, laboratory experiments, and models. I conclude with some of our remaining unanswered questions as the incredible era of exploration with Cassini-Huygens comes to an end.

11 Figures, 1 table, a lot of pages. Accepted in JGR Planets

References in corpus (24)

• Hubble Space Telescope Near-IR Transmission Spectroscopy of the Super-Earth HD 97658b
• GCM simulations of Titan's middle and lower atmosphere and comparison to observations
• Photolytically generated aerosols in the mesosphere and thermosphere of Titan
• Titan solar occultation observations reveal transit spectra of a hazy world
• Global circulation as the main source of cloud activity on Titan
• Ethyl cyanide on Titan: Spectroscopic detection and mapping using ALMA
• Titan's atmosphere as observed by Cassini/VIMS solar occultations: CH${}_4$, CO and evidence for C${}_2$H${}_6$ absorption
• Dissolution on Titan and on Earth: Towards the age of Titan's karstic landscapes
• HCN ice in Titan's high-altitude southern polar cloud
• ALMA measurements of the HNC and HC${}_3$N distributions in Titan's atmosphere
• Titan's Obliquity as evidence for a subsurface ocean?
• Methane storms as a driver of Titan's dune orientation
• The Origin of Nitrogen on Jupiter and Saturn from the ${}^{15}$N/${}^{14}$N Ratio
• Upper limits for undetected trace species in the stratosphere of Titan
• Simulations of Titan's paleoclimate
• Herschel/PACS spectroscopy of trace gases of the stratosphere of Titan
• The reflectance spectrum of Titan's surface at the Huygens landing site determined by the Descent Imager/Spectral Radiometer
• Discovery of lake-effect clouds on Titan
• Titan's past and future: 3D modeling of a pure nitrogen atmosphere and geological implications
• Bouncing on Titan: Motion of the Huygens Probe in the Seconds After Landing
• Observations of a Stationary Mid-Latitude Cloud System on Titan
• Upper limits for PH3 and H2S in Titan's Atmosphere from Cassini CIRS
• The 2003 Nov 14 occultation by Titan of TYC 1343-1865-1. II. Analysis of light curves
• HST observations of the limb polarization of Titan

Cited by in corpus (84)

• Observing the Atmospheres of Known Temperate Earth-sized Planets with JWST
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• Exoplanet Biosignatures: A Framework for Their Assessment
• ExoMol molecular line lists -- XXXVII: spectra of acetylene
• The Featureless Transmission Spectra of Two Super-Puff Planets
• The Case and Context for Atmospheric Methane as an Exoplanet Biosignature
• The Composition and Chemistry of Titan's Atmosphere
• HAZMAT. IV. Flares and Superflares on Young M Stars in the Far Ultraviolet
• Deflating Super-Puffs: Impact of Photochemical Hazes on the Observed Mass-Radius Relationship of Low Mass Planets
• Unveiling cloudy exoplanets: the influence of cloud model choices on retrieval solutions
• Detection of Cyclopropenylidene on Titan with ALMA
• Carbon Monoxide Affecting Planetary Atmospheric Chemistry
• Chemistry of Temperate Super-Earth and Mini-Neptune Atmospheric Hazes from Laboratory Experiments
• Laboratory Investigations of Titan Haze Formation: In Situ Measurement of Gas and Particle Composition
• Abundance Measurements of Titan's Stratospheric HCN, HC${}_3$N, C${}_3$H${}_4$, and CH${}_3$CN from ALMA Observations
• Towards RNA life on Early Earth: From atmospheric HCN to biomolecule production in warm little ponds
• The Role of Acetylene in the Chemical Evolution of Carbon Complexity
• The Fundamental Connections Between the Solar System and Exoplanetary Science
• A New Model Suite to Determine the Influence of Cosmic Rays on (Exo)planetary Atmospheric Biosignatures -- Validation based on Modern Earth
• Cleaning our Hazy Lens: Exploring Trends in Transmission Spectra of Warm Exoplanets
• Surface Energy of the Titan Aerosol Analog "Tholin"
• Detecting the proposed CH4-CO2 biosignature pair with the James Webb Space Telescope: TRAPPIST-1e and the effect of cloud/haze
• A Consistent Reduced Network for HCN Chemistry in Early Earth and Titan Atmospheres: Quantum Calculations of Reaction Rate Coefficients
• Where does Titan Sand Come From: Insight from Mechanical Properties of Titan Sand Candidates
• Albedos, Equilibrium Temperatures, and Surface Temperatures of Habitable Planets
• HCN production in Titan's Atmosphere: Coupling quantum chemistry and disequilibrium atmospheric modeling
• Atmospheric Dynamics on Terrestrial Planets: The Seasonal Response to changes in Orbital, Rotational and Radiative Timescales
• ALMA Spectral Imaging of Titan Contemporaneous with Cassini's Grand Finale
• Hydrocarbon chemistry in inner regions of planet forming disks
• Interferometric imaging of Titan's HC${}_3$N, H${}^{13}$CCCN and HCCC${}^{15}$N
• Evolution of Titan s high-altitude aerosols under ultraviolet irradiation
• An axisymmetric limit for the width of the Hadley cell on planets with large obliquity and long seasonality
• Hubble WFC3 Spectroscopy of the Rocky Planet L 98-59 b: No Evidence for a Cloud-Free Primordial Atmosphere
• Ions in the Thermosphere of Exoplanets: Observable Constraints Revealed by Innovative Laboratory Experiments
• Brown Dwarf Atmospheres as the Potentially Most Detectable and Abundant Sites for Life
• Photochemical hazes can trace the C/O ratio in exoplanet atmospheres
• Identification of organic molecules with a laboratory prototype based on the Laser Ablation-CosmOrbitrap
• Photoreactivity of condensed acetylene on Titan aerosols analogues
• Dynamics and Clouds in Planetary Atmospheres from Telescopic Observations
• Detection of Dynamical Instability in Titan's Thermospheric Jet
• The floatability of aerosols and waves damping on Titan's seas
• N2-H2 capacitively coupled radio-frequency discharges at low pressure. Part II. Modelling results: the relevance of plasma-surface interaction
• Haze Formation on Triton
• Material Properties of Organic Liquids, Ices, and Hazes on Titan
• Low Pressure EUV Photochemical Experiments: Insight on the Ion-Chemistry Occurring in Titan's Atmosphere
• Positive Ion Chemistry in an N${}_2$-CH${}_4$ Plasma Discharge: Key Precursors to the Growth of Titan Tholins
• Atmospheric circulation, chemistry, and infrared spectra of Titan-like exoplanets around different stellar types
• Phase Diagram for the Methane-Ethane System and its Implications for Titan's Lakes
• Low temperature formation of pyridine and (iso)quinoline via neutral neutral reactions
• Nitrogen Atmospheres of the Icy Bodies in the Solar System
• Experimental Characterization of the Pyridine:Acetylene Co-crystal and Implications for Titan's Surface
• Cloud and Haze Parameterization in Atmospheric Retrievals: Insights from Titan's Cassini Data and JWST Observations of Hot Jupiters
• Retrieval of Chemical Abundances in Titan's Upper Atmosphere from Cassini UVIS Observations with Pointing Motion
• Variability in Titan's Mesospheric HCN and Temperature Structure as Observed by ALMA
• 3D simulations of TRAPPIST-1e with varying CO2, CH4 and haze profiles
• The Atmosphere of Titan in Late Northern Summer from JWST and Keck Observations
• Detection opportunity for aromatic signature in Titan s aerosols in the 4.1 to 5.3 micron range
• Experimental and computational studies on the reactivity of methanimine radical cation (H${}_2$CNH${}^{+\cdot }$) and its isomer aminomethylene (HCNH${}_2^{+\cdot }$) with C${}_2$H${}_2$
• Ethane clathrate hydrate infrared signatures for solar system remote sensing
• The reactivity of methanimine radical cation (H${}_2$CNH${}^{+\cdot }$) and its isomer aminomethylene (HCNH${}_2^{+\cdot }$) with C${}_2$H${}_4$
• Mass Transport in a Moist Planetary Climate Model
• Theoretical constraints imposed by gradient detection and dispersal on microbial size in astrobiological environments
• Presence of liquid water during the evolution of exomoons orbiting ejected free-floating planets
• GEMS JWST: Transmission spectroscopy of TOI-5205b reveals significant stellar contamination and a metal-poor atmosphere
• Towards Prebiotic Chemistry on Titan: Impact experiments on organic haze particles
• The Detection-vs-Retrieval Challenge: Titan as an Exoplanet
• High-temperature measurements of acetylene VUV absorption cross sections and application to warm exoplanet atmospheres
• Measurements of Titan's Stratospheric Winds during the 2009 Equinox with the eSMA
• Formation of organic hazes in CO${}_2$-rich sub-Neptune atmospheres within the graphite-stability regime
• Photochemical Haze Formation on Titan and Uranus: A Comparative Review
• New Bistable Solutions in Molecular Cloud Chemistry: Nitrogen and Carbon Autocatalysis
• Sensitivity to Sub-Io-sized Exosatellite Transits in the MIRI LRS Lightcurve of the Nearest Substellar Worlds
• Rapid Automated Mapping of Clouds on Titan With Instance Segmentation
• Shock Synthesis of Organic Molecules by Meteoroids in the Atmosphere of Titan
• Discovery of a Nearby Habitable Zone Super-Earth Candidate Amenable to Direct Imaging
• Planetary Exploration Horizon 2061 Report, Chapter 4: From planetary exploration goals to technology requirements
• Information Transmission via Molecular Communication in Astrobiological Environments
• The Most Common Habitable Planets III -- Modeling Temperature Forcing and Surface Conditions on Rocky Exoplanets and Exomoons
• On the importance of laboratory experiments for interpreting exoplanet observations
• k-Means Aperture Optimization Applied to Kepler K2 Time Series Photometry of Titan
• TOI-3757 b: A low density gas giant orbiting a solar-metallicity M dwarf
• Evaluating Habitability and Biosignature Detection on TOI-700 d: The Role of UV Environment and Atmospheric Pressure
• Distributed Charge Models of Liquid Methane and Ethane for Dielectric Effects and Solvation
• Hydrocarbon complexity and photochemical shielding of prebiotic feedstock molecules in exoplanet atmospheres