English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

A planet's emission spectrum contains information about atmosphericcomposition and structure. We compare the Bayesian Information Criterion (BIC)of blackbody fits and idealized spectral retrieval fits for the 44 planets withpublished eclipse measurements in multiple thermal wavebands, mostly obtainedwith the Spitzer Space Telescope. The evidence for spectral features depends oneclipse depth uncertainties. Spitzer has proven capable of eclipse precisionsbetter than 1E-4 when multiple eclipses are analyzed simultaneously, but thisfeat has only been performed four times. It is harder to self-calibratephotometry when a single occultation is reduced and analyzed in isolation; wefind that such measurements have not passed the test of repeatability.Single-eclipse measurements either have an uncertainty floor of 5E-4, or theiruncertainties have been underestimated by a factor of 3. If one adopts theseempirical uncertainties for single-eclipse measurements, then the evidence formolecular features all but disappears: blackbodies have better BIC thanspectral retrieval for all planets, save HD 189733b, and the few planets poorlyfit by blackbodies are also poorly fit by self-consistent radiative transfermodels. This suggests that the features in extant broadband emission spectraare due to astrophysical and instrumental noise rather than molecular bands.Claims of stratospheric inversions, disequilibrium chemistry, and high C/Oratios based solely on photometry are premature. We recommend that observers becautious of error estimates from self-calibration of small data sets, and thatmodelers compare the evidence for spectral models to that of simpler modelssuch as blackbodies.

Features in the Broadband Eclipse Spectra of Exoplanets: Signal or Noise?