Five key exoplanet questions answered via the analysis of 25 hot Jupiter atmospheres in eclipse

TL;DR

This study analyzes 25 hot Jupiter atmospheres using eclipse data from space telescopes to identify robust trends in their thermal and chemical properties, advancing our understanding of exoplanet populations.

Contribution

It applies a uniform retrieval analysis to a large sample of hot Jupiters, revealing new population-level insights into their atmospheres.

Findings

Identified consistent thermal structure trends among hot Jupiters.

Detected common chemical signatures across the sample.

Established a framework for future population-based atmospheric studies.

Abstract

Population studies of exoplanets are key to unlocking their statistical properties. So far the inferred properties have been mostly limited to planetary, orbital and stellar parameters extracted from, e.g., Kepler, radial velocity, and GAIA data. More recently an increasing number of exoplanet atmospheres have been observed in detail from space and the ground. Generally, however, these atmospheric studies have focused on individual planets, with the exception of a couple of works which have detected the presence of water vapor and clouds in populations of gaseous planets via transmission spectroscopy. Here, using a suite of retrieval tools, we analyse spectroscopic and photometric data of 25 hot Jupiters, obtained with the Hubble and Spitzer Space Telescopes via the eclipse technique. By applying the tools uniformly across the entire set of 25 planets, we extract robust trends in the thermal structure and chemical properties of hot Jupiters not obtained in past studies. With the recent launch of JWST and the upcoming missions Twinkle, and Ariel, population based studies of exoplanet atmospheres, such as the one presented here, will be a key approach to understanding planet characteristics, formation, and evolution in our galaxy.