Three research directions natural in the 2017 setting are:
- Atmospheric characterization of small planets, extending beyond bright hot Jupiters to super-Earth-sized and terrestrial bodies. The aim is to determine whether they retain light envelopes or heavier secondary atmospheres and to understand exoplanet habitability. Potential exoplanet biosignatures require a chemical and stellar context because abiotic processes can mimic individual molecules; future infrared observatories such as the then-planned James Webb Space Telescope offered a route to better spectra, without guaranteeing a biological interpretation.
- Connecting measured composition to planet formation and planetary migration. Atmospheric metallicity of a giant planet, atmospheric carbon-to-oxygen ratio, orbital architecture and bulk mass-radius measurements can constrain accretion of gas and solids. Atmospheric condensate rainout, disequilibrium chemistry in an exoplanet atmosphere and exoplanet interior-composition degeneracy make a one-to-one mapping from a measured ratio to a birth location unreliable; comparative samples and coupled models are needed.
- Resolving atmospheric structure in space and time. Exoplanet thermal phase curves, repeated spectra, high-resolution planetary spectroscopy and exoplanet direct imaging can test day-night heat redistribution, winds, patchy exoplanet clouds, atmospheric escape and chemical heterogeneity. The challenge is to distinguish actual variability or circulation from changes in stellar light and instrumental calibration.
Articles by others on the same topic
There are currently no matching articles.