2003/12/15 by J. -M. Désert, Jean-Michel Désert, Désert, J. -M. +14
Physics and Astronomy · #Astro and Planetary Science #Astrophysics (astro-ph) #FOS: Physical sciences #Solar and Space Plasma Dynamics #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/0312383
To be published in the proceedings of the XIXth IAP Colloquium "Extrasolar Planets, Today and Tomorrow", 2 pages
arxiv created 2003/12/15 · openalex publication_date 2003/12/15 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Using STIS - HST observations, we have detected an extended upper atmosphere in the extrasolar planet HD209458b . The spectra show an absorption of (15+/-4)% of the stellar Ly-alpha emission line during the planetary transit in front of the star. This is interpreted as the signature of HI evaporation taking place around the planet within an extended upper atmosphere (Vidal-Madjar et al. 2003). We present the data analysis of these observations. A particular attention is paid to the background correction and the airglow subtraction.