1999/08/31 by D. P. Bennett, Sun Hong Rhie, S. H. Rhie +19 · 98 citations
Physics and Astronomy · #Astro and Planetary Science #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Binary star #Exoplanet #Gravitational microlensing #Jovian #Physics #Planet #Planetary system #Stars #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.1038/46990
published in Nature 402(6757), 57-59 (Nature Portfolio) · 11 pages, with 1 color and 2 b/w Figures included (published version)
openalex publication_date 1999/11/01 · arxiv created 1999/11/04 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The study of extra-solar planetary systems has emerged as a new discipline of observational astronomy in the past few years with the discovery of a number of extra-solar planets. The properties of most of these extra-solar planets were not anticipated by theoretical work on the formation of planetary systems. Here we report observations and light curve modeling of gravitational microlensing event MACHO-97-BLG-41, which indicates that the lens system consists of a planet orbiting a binary star system. According to this model, the mass ratio of the binary star system is 3.8:1 and the stars are most likely to be a late K dwarf and an M dwarf with a separation of about 1.8 AU. A planet of about 3 Jupiter masses orbits this system at a distance of about 7 AU. If our interpretation of this light curve is correct, it represents the first discovery of a planet orbiting a binary star system and the first detection of a Jovian planet via the gravitational microlensing technique. It suggests that giant planets may be common in short period binary star systems.