A Pair of Resonant Planets Orbiting GJ 876

  title={A Pair of Resonant Planets Orbiting GJ 876},
  author={G. Marcy and R. Butler and D. Fischer and S. Vogt and J. Lissauer and E. Rivera},
  journal={The Astrophysical Journal},
Precise Doppler measurements during 6 yr from the Lick and Keck observatories reveal two planets orbiting GJ 876 (M4V). The orbital Ðt yields companion masses of M sin i \ 0.56 and 1.89 orbital M J , periods of P \ 30.1 and 61.0 days, semimajor axes of a \ 0.13 and 0.21 AU, and eccentricities of e \ 0.28 and 0.10, respectively. The orbital periods are nearly in the ratio of 2:1, unprecedented among major planets but common among moons and asteroids. Moreover, the axes of the elliptical orbits… Expand
A Second Planet Orbiting 47 Ursae Majoris
Precise Doppler velocity measurements during 13 yr at Lick Observatory reveal the presence of two planets orbiting the star 47 UMa. The previously detected inner planet is confirmed by the newerExpand
On the Double-Planet System around HD 83443
The Geneva group has reported two Saturn-mass planets orbiting HD 83443 (K0 V) with periods of 2.98 and 29.8 days. The two planets have raised interest in their dynamics because of the possible 10 :Expand
A Neptune-Mass Planet Orbiting the Nearby M Dwarf GJ 436
We report precise Doppler measurements of GJ 436 (M2.5 V) obtained at Keck Observatory. The velocities reveal a planetary companion with orbital period of 2.644 days, eccentricity of 0.12 (consistentExpand
Global dynamics of the Gliese 876 planetary system
The Gliese 876 planetary system consists of two Jupiter-like planets having a nearly commensurate 2:1 orbital periods ratio. Because the semimajor axes of the planets are very small (of the order 0.1Expand
The HARPS search for southern extra-solar planets - XIX. Characterization and dynamics of the GJ 876 planetary system
Precise radial-velocity measurements for data acquired with the HARPS spectrograph infer that three planets orbit the M4 dwarf star GJ876. In particular, we confirm the existence of planet d, whichExpand
Dynamical Models of the Resonant Pair of Planets Orbiting the Star GJ 876
We present two planet fits to the radial velocity measurements of the M dwarf star GJ 876 that account for the mutual perturbations between the planets, as well as their interactions with the star.Expand
Modeling the resonant planetary system GJ 876
The two planets about the star GJ 876 appear to have undergone extensive migration from their point of origin in the protoplanetary disk – both because of their close proximity to the star (30 and 60Expand
Possible scenarios for eccentricity evolution in the extrasolar planetary system HD 181433
We analyse the dynamics of the multiple planet system HD 181433. This consists of two gas giant planets (bodies c and d) with msini = 0.65 MJup and 0.53 MJup orbiting with periods 975 and 2468 days,Expand
On the 2:1 Orbital Resonance in the HD 82943 Planetary System
We present an analysis of the HD 82943 planetary system based on a radial velocity data set that combines new measurements obtained with the Keck telescope and the CORALIE measurements published inExpand
A ~7.5 M⊕ Planet Orbiting the Nearby Star, GJ 876*
High-precision, high-cadence radial velocity monitoring over the past 8 yr at the W. M. Keck Observatory reveals evidence for a third planet orbiting the nearby (4.69 pc) dM4 star GJ 876. TheExpand


A Planetary Companion to a Nearby M4 Dwarf, Gliese 876*
Doppler measurements of the M4 dwarf star Gliese 876 taken at both Lick and Keck Observatories reveal periodic, Keplerian velocity variations with a period of 61 days. The orbital fit implies thatExpand
Planetary Companions to the Metal-rich Stars BD –10°3166 and HD 52265*
Precise Doppler measurements from the Keck/HIRES spectrometer reveal periodic Keplerian velocity variations in the stars BD -10°3166 and HD 52265. BD -10°3166 (K0 V) has a period of 3.487 days and aExpand
Evidence for Multiple Companions to υ Andromedae
The bright F8 V star t Andromedae was previously reported to have a 4.6 day Doppler velocity periodicity, consistent with having a Jupiter-mass companion orbiting at 0.059 AU. Follow-up obser-Expand
Stability Analysis of the Planetary System Orbiting υ Andromedae
We present numerical orbital integrations designed to test the stability of the three planets detected in orbit around υ Andromedae and possible smaller bodies orbiting in the system which have notExpand
Planetary Companions to HD 12661, HD 92788, and HD 38529 and Variations in Keplerian Residuals of Extrasolar Planets
Precision Doppler observations at the Lick and Keck observatories have revealed Keplerian velocity variations in the stars HD 12661, HD 92788, and HD 38529. HD 12661 (G6 V) has an orbital period ofExpand
Nebular gas drag and planetary accretion. II. Planet on an eccentric orbit.
Abstract We study the trajectories of planetesimals whose orbits decay starward as a result of gas drag and are perturbed by the gravity of a massive planet on an eccentric orbit. Each planetesimalExpand
Orbital Resonances in the Solar System
Orbital resonances are defined as any system of two or more satellites (including planets) orbiting the same primary and whose orbital mean motions are in a ratio of small whole numbers. KnownExpand
The boundaries of the Uranian ∈, α, and β rings can be fitted by Keplerian ellipses. The pair of ellipses that outline a given ring share a common line of apsides. Apse alignment is surprisingExpand
Survival of Planetary Systems
Gravitational interactions (i.e., disk tides) between a newly formed protoplanet and its precursor disk give rise to a net torque that drains angular momentum from the protoplanet's orbit. As aExpand
Current spectroscopic techniques yield Doppler-shift errors of 10 to 50 m s-1, barely adequate to detect reflex velocities caused by Jupiter-like and lower-mass planets. We describe a technique whichExpand