Titan Science with the James Webb Space Telescope (JWST)

Abstract

The James Webb Space Telescope (JWST), scheduled for launch in 2018, is the successor to the Hubble Space Telescope (HST) but with a significantly larger aperture (6.5 m) and advanced instrumentation focusing on infrared science (0.6-28.0 $\mu$m ). In this paper we examine the potential for scientific investigation of Titan using JWST, primarily with three of the four instruments: NIRSpec, NIRCam and MIRI, noting that science with NIRISS will be complementary. Five core scientific themes are identified: (i) surface (ii) tropospheric clouds (iii) tropospheric gases (iv) stratospheric composition and (v) stratospheric hazes. We discuss each theme in depth, including the scientific purpose, capabilities and limitations of the instrument suite, and suggested observing schemes. We pay particular attention to saturation, which is a problem for all three instruments, but may be alleviated for NIRCam through use of selecting small sub-arrays of the detectors - sufficient to encompass Titan, but with significantly faster read-out times. We find that JWST has very significant potential for advancing Titan science, with a spectral resolution exceeding the Cassini instrument suite at near-infrared wavelengths, and a spatial resolution exceeding HST at the same wavelengths. In particular, JWST will be valuable for time-domain monitoring of Titan, given a five to ten year expected lifetime for the observatory, for example monitoring the seasonal appearance of clouds. JWST observations in the post-Cassini period will complement those of other large facilities such as HST, ALMA, SOFIA and next-generation ground-based telescopes (TMT, GMT, EELT).

50 pages, including 22 figures and 2 tables

References in corpus (13)

• Submillimeter Observations of Titan: Global Measures of Stratospheric Temperature, CO, HCN, HC3N, and the Isotopic Ratios 12C/13C and 14N/15N
• Detection of Propene in Titan's Stratosphere
• Global circulation as the main source of cloud activity on Titan
• Ethyl cyanide on Titan: Spectroscopic detection and mapping using ALMA
• Cassini/VIMS hyperspectral observations of the HUYGENS landing site on Titan
• Titan's atmosphere as observed by Cassini/VIMS solar occultations: CH${}_4$, CO and evidence for C${}_2$H${}_6$ absorption
• Evidence of Titan's Climate History from Evaporite Distribution
• 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 Prolific Propane: The Cassini CIRS Perspective
• Upper limits for undetected trace species in the stratosphere of Titan
• Giant Planet Observations with the James Webb Space Telescope
• The Near-IR Spectrum of Titan Modeled with an Improved Methane Line List

Cited by in corpus (10)

• The Composition and Chemistry of Titan's Atmosphere
• In situ Investigation of Neutrals Involved in the Formation of Titan Tholins
• The James Webb Space Telescopes plan for operations and instrument capabilities for observations in the Solar System
• Dynamics and Clouds in Planetary Atmospheres from Telescopic Observations
• Small Bodies Science with Twinkle
• Observing Outer Planet Satellites (except Titan) with JWST: Science Justification and Observational Requirements
• Spitzer IRS Observations of Titan as a Precursor to JWST MIRI Observations
• Remote-sensing Characterisation of Major Solar System Bodies with the Twinkle Space Telescope
• Photochemical Haze Formation on Titan and Uranus: A Comparative Review
• Open Questions and Future Directions in Titan Science