Beta Pictoris

Dynamics of the Beta Pictoris Planetary System and Possibility of an Additional Planet

By Keith Cowing

Status Report

astro-ph.EP

January 12, 2025

Filed under astro-ph.EP, astronomy, Beta PIctoris, beta Pictoris b, Beta Pictoris c, exoplanet, imaging, Terrestrial Planet

Dynamics of the Beta Pictoris Planetary System and Possibility of an Additional Planet — Preliminary simulation of the dynamics of the β Pic planetary system with only the two planets known to date, β Pic b (red) and β Pic c (blue), and the disk of planetesimals (black). The initial orbital parameters of β Pic b and c are taken from Table 1. Left: upper view of the system. The planetesimals are depicted by small black dots, and the orbits of the planets by colored dashed lines. Middle: view of the system in terms of semi-major axis and eccentricity. The planets are here represented by colored points. Right: radial profile of the planetesimal disk (solid black line), superimposed to the models of Augereau et al. (2001) (blue dotted line) and Dent et al. (2014) (red dotted line). Note the clear mismatch in the location of the inner edge between this simulation and observational models. — astro-ph.EP

The Beta Pictoris system is characterized by a dusty debris disk, in addition to the presence of two already known planets. This makes it a particularly interesting case for studying the formation and evolution of planetary systems at a stage where giant planets have already formed, most of the protoplanetary gas has dissipated, and terrestrial planets could emerge.

Our goal here is to explore the possibility of additional planets orbiting beyond the outermost known one, β Pic b. More specifically, we aim to assess whether additional planets in the system could explain the discrepancy between the predicted cutoff of the disk inner cavity at ∼28 au with only two planets, and the observed one at ∼50 au.

We perform an exhaustive dynamical modeling of the debris disk and the carving of its inner edge, by introducing one or two additional planets beyond β Pic b, coplanar with the disk. Guided by theoretical predictions for the parameter space – mass, semi-major axis, eccentricity – allowed for additional planets, we further carry out a set of N-body simulations, using the symplectic integrator RMVS3.

Our simulations indicate that an additional planet with a low eccentricity of 0.05, a mass between 0.15 and 1 M_Jup, and a semi-major axis between 30 and 36 au, would be consistent with the observations of an inner debris disk edge at 50 au. We have also explored the hypotheses of a higher eccentricity and the presence of two additional lower mass planets instead of one, which could also account for these observations.

While we have found that one or even two additional planets could explain the observed location of the disk inner edge, these hypothetical planets remain in most cases below the current observational limits of high contrast imaging. Future observational campaigns with improved sensitivity will help lowering these limits and perhaps detect that planet.

A. Lacquement, H. Beust, V. Faramaz-Gorka, G. Duchêne

Comments: Accepted for publication in A&A on December 27, 2024
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:2501.03143 [astro-ph.EP] (or arXiv:2501.03143v1 [astro-ph.EP] for this version)
https://doi.org/10.48550/arXiv.2501.03143
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Submission history
From: Antoine Lacquement
[v1] Mon, 6 Jan 2025 17:08:04 UTC (1,229 KB)
https://arxiv.org/abs/2501.03143
Astrobiology,

Keith Cowing

Explorers Club Fellow, ex-NASA Space Station Payload manager/space biologist, Away Teams, Journalist, Lapsed climber, Synaesthete, Na’Vi-Jedi-Freman-Buddhist-mix, ASL, Devon Island and Everest Base Camp veteran, (he/him) 🖖🏻

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