NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Back to Results
HAT-P-7: A Retrograde or Polar Orbit, and a Third BodyWe showed that the exoplanet HAT-P-7b has an extremely tilted orbit, with a true angle of at least 86 degrees with respect to its parent star's equatorial plane, and a strong possibility of retrograde motion. We also report evidence for an additional planet or companion star. The Rossiter-McLaughlin effect was found to be a blueshift during the first half of the transit and a redshift during the second half, an inversion of the usual pattern, implying that the angle between the sky-projected orbital and stellar angular momentum vectors is 182.5 plus or minus 9.4 degrees. The third body is implicated by excess RV variation of the host star over 2 yr. Some possible explanations for the tilted orbit of HAT-P-7b are a close encounter with another planet, the Kozai effect, and resonant capture by an inward-migrating outer planet.
Document ID
20090037191
Acquisition Source
Headquarters
Document Type
Reprint (Version printed in journal)
Authors
Winn, Joshua N.
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Johnson, John Asher
(Hawaii Univ. Honolulu, HI, United States)
Albrecht, Simon
(Massachusetts Inst. of Tech. Cambridge, MA, United States)
Howard, Andrew W.
(California Univ. Berkeley, CA, United States)
Marcy, Geoffrey W.
(California Univ. Berkeley, CA, United States)
Crossfield, Ian J.
(California Univ. Los Angeles, CA, United States)
Holman, Matthew J.
(Harvard-Smithsonian Center for Astrophysics Cambridge, MA, United States)
Date Acquired
August 24, 2013
Publication Date
October 1, 2009
Publication Information
Publication: Astrophysical Journal Letters
Volume: 703
Issue: 2
Subject Category
Astrophysics
Funding Number(s)
CONTRACT_GRANT: NNX09AD36G
Distribution Limits
Public
Copyright
Other

Available Downloads

There are no available downloads for this record.
No Preview Available