Status Report

The 3-dimensional architecture of the Upsilon Andromedae planetary system

By SpaceRef Editor
November 6, 2014
Filed under , , ,

Russell Deitrick, Rory Barnes, Barbara McArthur, Thomas R. Quinn, Rodrigo Luger, Adrienne Antonsen, G. Fritz Benedict

(Submitted on 4 Nov 2014)

The Upsilon Andromedae system is the first exoplanetary system to have the relative inclination of two planets’ orbital planes directly measured, and therefore offers our first window into the 3-dimensional configurations of planetary systems. We present, for the first time, full 3-dimensional, dynamically stable configurations for the 3 planets of the system consistent with all observational constraints. While the outer 2 planets, c and d, are inclined by about 30 degrees, the inner planet’s orbital plane has not been detected. We use N-body simulations to search for stable 3-planet configurations that are consistent with the combined radial velocity and astrometric solution. We find that only 10 trials out of 1000 are robustly stable on 100 Myr timescales, or about 8 billion orbits of planet b. Planet b’s orbit must lie near the invariable plane of planets c and d, but can be either prograde or retrograde. These solutions predict b’s mass is in the range 2 – 9

MJup and has an inclination angle from the sky plane of less than 25 degrees. Combined with brightness variations in the combined star/planet light curve (“phase curve”), our results imply that planet b’s radius is about 1.8RJup, relatively large for a planet of its age. However, the eccentricity of b in several of our stable solutions reaches values greater than 0.1, generating upwards of

10 19 watts in the interior of the planet via tidal dissipation, possibly inflating the radius to an amount consistent with phase curve observations.

Comments: 17 pages, 10 figures, accepted for publication in ApJ

Subjects: Earth and Planetary Astrophysics (astro-ph.EP)

Cite as: arXiv:1411.1059 [astro-ph.EP](or arXiv:1411.1059v1 [astro-ph.EP] for this version)

Submission history

From: Russell Deitrick 

[v1] Tue, 4 Nov 2014 21:00:04 GMT (912kb,D)

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