The Radius of the "Super-Neptune" HD 149026b
Abstract
Current measurements suggest that the transiting exoplanet HD 149026bis a "super-Neptune," with an enormous heavy-element core. Theexistence of such a planet is a major challenge to planet formationtheories. We propose to place the radius measurement on much firmerfooting, by obtaining a NICMOS light curve with 0.4 mmag precisionand 13 sec cadence. We will improve the radius measurement by a factorof 2.3, and more importantly, the result will be more robust becausewe will determine the stellar radius directly from the data. Numerousattempts to do this from the ground have failed.
- Publication:
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HST Proposal
- Pub Date:
- July 2007
- Bibcode:
- 2007hst..prop11165W