P. D. Shankland (US Naval Obs/James Cook Uni), D. Blank (Uni W. Sydney), G. Laughlin (UCO/Lick Observatory), A. Price, B. Gary, R. Bissinger (AAVSO), F. Ringwald (Cal State Uni, Fresno), G. White (James Cook Uni), M. Ashbey (Uni New S. Wales), J. Greenhill (Uni Tasmania), P. McGee (Uni. Adelaide), S. Sinclair (Wollongong Sci. Ctr, NSW), B. Carter (Uni S. Queensland), S. Lee (AAT), J. Biggs (Perth Obsy), V. Tabur (Mt. Stromlo Obsy/ANU), A. Roy (MPIFR, Bonn), R. Santallo (AAVSO), P. Kilmartin (AAVSO/Mt St. John Uni NZ), D. Higgins, P. Nelson, T. Richards, B. Heathcote, C. Stockdale, Z. Kereszty, J.L. Laurent, P. de Ponthiere (AAVSO), K. J. Johnston (USNO), J. Lazio (Naval Research Lab), C. Knapp, S. Dvorak, M. Fleenor, J. Case (AAVSO), M. Koppelman (AAVSO/Uni Minnesota), D. Wells, W. Dillon, R. Koff, R. James, J. Holtzman, R. Huziak (AAVSO)
Abstract: Radial Velocity Observations have shown that the nearby M4 V dwarf GJ 876 is accompanied by two massive planets in a 2:1 mean motion resonance (Marcy et al 2001). Astrometric observations with HST (Benedict et al 2002) suggest that the plane of the outer planet has an inclination, i=84\circ ±6\circ, indicating that the system is a good candidate for photometric follow-up to check for transits of the two planets. We report results from a multi-observer campaign carried out during 2004, which indicate that neither planet is currently transiting. We present dynamical models of the system which indicate that future transits of the inner planet may be observed in the future, provided that the orbital planes of the two planets possess several degrees of mutual inclination.
refs: Marcy et al 2001, ApJ, 556, 296 Benedict et al 2002, ApJL, 581, 115
The author(s) of this abstract have provided an email address for comments about the abstract: paul.shankland@navy.mil
Bulletin of the American Astronomical Society, 37 #2
© 2005. The American Astronomical Soceity.