WASP-41b: A Transiting Hot Jupiter Planet Orbiting a Magnetically Active G8V Star

Research output: Contribution to journalArticlepeer-review


  • P.~F.~L. Maxted
  • D.~R. Anderson
  • A. Collier Cameron
  • C. Hellier
  • D. Queloz
  • B. Smalley
  • R.~A. Street
  • R.~G. West
  • M. Gillon
  • T.~A. Lister
  • F. Pepe
  • D. Pollacco
  • D. Ségransan
  • A.~M.~S. Smith
  • S. Udry

Colleges, School and Institutes


We report the discovery of a transiting planet with an orbital period of 3.05 days orbiting the star TYC 7247-587-1. The star, WASP-41, is a moderately bright G8 V star (V = 11.6) with a metallicity close to solar ([Fe/H] = -0.08 plusmn 0.09). The star shows evidence of moderate chromospheric activity, both from emission in the cores of the Ca ii H and K ines and photometric variability with a period of 18.4 days and an amplitude of about 1 We use a new method to show quantitatively that this periodic signal has a low false-alarm probability. The rotation period of the star implies a gyrochronological age for WASP-41 of 1.8 Gyr with an error of about 15 We have used a combined analysis of the available photometric and spectroscopic data to derive the mass and radius of the planet (0.92 plusmn 0.06 M$_Jup$, 1.20 plusmn 0.06 R$_Jup$). Further observations of WASP-41 can be used to explore the connections between the properties of hot Jupiter planets and the level of chromospheric activity in their host stars.


Original languageEnglish
Pages (from-to)547
Number of pages1
JournalPublications of the Astronomical Society of the Pacific
Publication statusPublished - 1 May 2011