G. Zhou, D. Bayliss
Jul 30, 2012
Citations
3
Influential Citations
33
Citations
Journal
Monthly Notices of the Royal Astronomical Society
Abstract
We present the detection of sodium absorption in the atmosphere of the extrasolar planet WASP-17b, an inflated ‘hot Jupiter’ in a tight orbit around an F6 dwarf. In-transit observations of WASP-17 made with the Magellan Inamori Kyocera Echelle (MIKE) spectrograph on the 6.5-m Magellan Telescope were analysed for excess planetary atmospheric absorption in the Na i ‘D’ doublet spectral region. Using the interstellar sodium absorption lines as reference, we detect a 0.58 ± 0.13 per cent transit signal, with 4.5σ confidence, at 1.5 A bandwidth around the stellar sodium absorption feature. This result is consistent with the previous Very Large Telescope detection of sodium in WASP-17b, confirming that the planet has a highly inflated atmosphere.