Related papers: Exploring the Sub-Neptune Frontier with JWST
Recent JWST observations of the sub-Neptune GJ 1214 b suggest that it hosts a high-metallicity (>100x solar), hazy atmosphere. Emission spectra of the planet show molecular absorption features, most likely due to atmospheric H2O. In light…
Common features of sub-Neptunes atmospheres observed to date include signatures of aerosols at moderate equilibrium temperatures (~500-800 K), and a prevalence of high mean molecular weight atmospheres, perhaps indicating novel classes of…
Traditionally, the search for life on exoplanets has been predominantly focused on rocky exoplanets. Hycean worlds are a class of habitable sub-Neptunes with planet-wide oceans and H2-rich atmospheres. Their broad range of possible sizes…
The first transmission spectrum of the habitable-zone sub-Neptune K2-18 b with JWST has opened a new avenue for atmospheric characterisation of temperate low-mass exoplanets. The observations led to inferences of methane and carbon dioxide,…
With the upcoming launch of space telescopes dedicated to the study of exoplanets, the \textit{Atmospheric Remote-Sensing Infrared Exoplanet Large-survey} (ARIEL) and the \textit{James Webb Space Telescope} (JWST), a new era is opening in…
Recent transit observations of K2-18b and TOI-270d revealed strong molecular absorption signatures, lending credence to the idea that temperate sub-Neptunes (T$_\mathrm{eq}$=250-400K) have upper atmospheres mostly free of aerosols. These…
One of the most profound questions about the newly discovered class of low-density super-Earths is whether these exoplanets are predominately H2-dominated mini-Neptunes or volatile-rich worlds with gas envelopes dominated by H2O, CO2, CO,…
Quantifying disequilibria is important to understand whether an environment could be habitable. It has been proposed that the exoplanet K2-18b has a hydrogen-rich atmosphere and a water ocean, making it a "hycean world". The James Webb…
Small planets ($\sim$1--3.9 $\Rearth$) constitute more than half of the inventory of the 4000-plus exoplanets discovered so far. Smaller planets are sufficiently dense to be rocky, but those with radii larger than $\sim$1.6 $\Rearth$ are…
The TRAPPIST-1 system is home to at least seven terrestrial planets and is a target of interest for future James Webb Space Telescope (JWST) observations. Additionally, these planets will be of interest to future missions making…
The James Webb Space Telescope (JWST) is expected to revolutionize the field of exoplanets. The broad wavelength coverage and the high sensitivity of its instruments will allow characterization of exoplanetary atmospheres with unprecedented…
The search for signs of life on other worlds has largely focused on terrestrial planets. Recent work, however, argues that life could exist in the atmospheres of temperate sub-Neptunes. Here, we evaluate the usefulness of carbon dioxide…
Recently, the James Webb Space Telescope has enabled detailed spectroscopic characterization of sub-Neptune atmospheres. With detections of carbon- and oxygen-bearing species such as CO, CO$_2$, CH$_4$, and H$_2$O, a central question is…
The James Webb Space Telescope (JWST) will offer the first opportunity to characterize terrestrial exoplanets with sufficient precision to identify high mean molecular weight atmospheres, and TRAPPIST-1's seven known transiting Earth-sized…
Atmospheric characterisation of temperate sub-Neptunes is the new frontier of exoplanetary science with recent JWST observations of possible Hycean world K2-18b. Accurate modelling of atmospheric processes is essential to interpreting…
Unlocking the atmospheres of sub-Neptunes is among JWST's major achievements, yet such observations demand complex analyses that strongly affect interpretations. We present an independent reanalysis of the original JWST transmission…
Neptune-size exoplanets are less studied as characterizing their atmospheres presents challenges due to their relatively small radius and atmospheric scale height. As the most common outcome of planet formation, these planets are crucial…
The population of short-period giant exoplanets around M-dwarf stars is slowly rising. These planets present an extraordinary opportunity for atmospheric characterisation and defy our current understanding of planetary formation.…
In the last few years astronomical surveys have expanded the reach of planetary science into the realm of small and dense extrasolar worlds. These share a number of characteristics with the terrestrial and icy planetary objects of the Solar…
Exoplanets orbiting M dwarfs present a valuable opportunity for their detection and atmospheric characterisation. This is evident from recent inferences of H$_2$O in such atmospheres, including that of the habitable-zone exoplanet K2-18b.…