Journal article icon

Journal article

A continuum from clear to cloudy hot-Jupiter exoplanets without primordial water depletion

Abstract:
Thousands of transiting exoplanets have been discovered, but spectral analysis of their atmospheres has so far been dominated by a small number of exoplanets and data spanning relatively narrow wavelength ranges (such as 1.1–1.7 micrometres). Recent studies show that some hot-Jupiter exoplanets have much weaker water absorption features in their near-infrared spectra than predicted1,2,3,4,5. The low amplitude of water signatures could be explained by very low water abundances6,7,8, which may be a sign that water was depleted in the protoplanetary disk at the planet’s formation location9, but it is unclear whether this level of depletion can actually occur. Alternatively, these weak signals could be the result of obscuration by clouds or hazes1,2,3,4, as found in some optical spectra3,4,10,11. Here we report results from a comparative study of ten hot Jupiters covering the wavelength range 0.3–5 micrometres, which allows us to resolve both the optical scattering and infrared molecular absorption spectroscopically. Our results reveal a diverse group of hot Jupiters that exhibit a continuum from clear to cloudy atmospheres. We find that the difference between the planetary radius measured at optical and infrared wavelengths is an effective metric for distinguishing different atmosphere types. The difference correlates with the spectral strength of water, so that strong water absorption lines are seen in clear-atmosphere planets and the weakest features are associated with clouds and hazes. This result strongly suggests that primordial water depletion during formation is unlikely and that clouds and hazes are the cause of weaker spectral signatures.
Publication status:
Published
Peer review status:
Peer reviewed

Actions


Access Document


Files:
Publisher copy:
10.1038/nature16068

Authors


More by this author
Role:
Author
ORCID:
0000-0001-6050-7645
More by this author
Role:
Author
ORCID:
0000-0003-4328-3867


Publisher:
Nature Research
Journal:
Nature More from this journal
Volume:
529
Pages:
59-62
Publication date:
2015-12-14
Acceptance date:
2015-10-01
DOI:
EISSN:
1476-4687
ISSN:
0028-0836
Pmid:
26675732


Language:
English
Keywords:
Pubs id:
pubs:580194
UUID:
uuid:04a9fdf2-2e5b-4b35-9916-01cd34f0ea15
Local pid:
pubs:580194
Source identifiers:
580194
Deposit date:
2018-01-23

Terms of use



Views and Downloads






If you are the owner of this record, you can report an update to it here: Report update to this record

TO TOP