Hubble Space Telescope stis optical transit transmission spectra of the hot Jupiter HD 209458b

David K. Sing, A. Vidal-Madjar, J. M. Désert, A. Lecavelier Des Etangs, G. Ballester

Research output: Contribution to journalArticlepeer-review

123 Scopus citations


We present the transmission spectra of the hot Jupiter HD 209458b taken with the Space Telescope Imaging Spectrograph aboard the Hubble Space Telescope. Our analysis combines data at two resolutions and applies a complete pixel-by-pixel limb-darkening correction to fully reveal the spectral line shapes of atmospheric absorption features. Terrestrial-based Na i and H i contamination are identified that mask the strong exoplanetary absorption signature in the Na core, which we find reaches total absorption levels of ∼0.11 % in a 4.4 Åband. The Na spectral line profile is characterized by a wide absorption profile at the lowest absorption depths and a sharp transition to a narrow absorption profile at higher absorption values. The transmission spectra also show the presence of an additional absorber at ∼6250 Å, observed at both medium and low resolutions. We performed various limb-darkening tests, including using high-precision limb-darkening measurements of the Sun to characterize a general trend of ATLAS models to slightly overestimate the amount of limb darkening at all wavelengths, likely due to the limitations of the model's one-dimensional nature. We conclude that, despite these limitations, ATLAS models can still successfully model limb darkening in high signal-to-noise ratio transits of solar-type stars, like HD 209458, to a high level of precision over the entire optical regime (3000-10000 Å) at transit phases between second and third contact.

Original languageEnglish (US)
Pages (from-to)658-666
Number of pages9
JournalAstrophysical Journal
Issue number1
StatePublished - Oct 10 2008


  • Methods: data analysis
  • Planetary systems
  • Stars: individual (HD 209458)

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Hubble Space Telescope stis optical transit transmission spectra of the hot Jupiter HD 209458b'. Together they form a unique fingerprint.

Cite this