Alpha Centauri

Alpha Centauri: Disc Dynamics, Planet Stability, Detectability

By Keith Cowing
Status Report
astro-ph.EP
January 31, 2024
Filed under , , ,
Alpha Centauri: Disc Dynamics, Planet Stability, Detectability
Gas column density of the Phantom hydrodynamical simulation of the circumstellar discs in the binary Alpha Centauri. The stars start at apoastron: A is in the top left corner, and B is in the bottom right corner. From left to right and top to bottom, we show the system at different evolutionary stages: 0, 0.5, 1, 1.5, 2.0, 2.5, 3, and 5 Pb , where Pb is a binary orbital period. The red dots represent the stars of Alpha Centauri. — astro-ph.EP

Alpha Centauri is a triple stellar system, and it contains the closest star to Earth (Proxima Centauri). Over the last decades, the stars in Alpha Cen and their orbits have been investigated in great detail.

However, the possible scenarios for planet formation and evolution in this triple stellar system remain to be explored further. First, we present a 3D hydrodynamical simulation of the circumstellar discs in the binary Alpha Cen AB.

Then, we compute stability maps for the planets within Alpha Cen obtained through N-body integrations. Last, we estimate the radial velocity (RV) signals of such planets. We find that the circumstellar discs within the binary cannot exceed 3 au in radius and that the available dust mass to form planets is about 30 M⊕.

Planets around A and B are stable if their semimajor axes are below 3 au, while those around C are stable and remain unperturbed by the binary AB. For rocky planets, the planetary mass has only a mild effect on the stability. Therefore, Alpha Cen could have formed and hosted rocky planets around each star, which may be detected with RV methods in the future. The exoplanetary hunt in this triple stellar system must continue.

Nicolás Cuello, Mario Sucerquia

Comments: 17 pages, 12 figures, accepted for publication in Universe
Subjects: Earth and Planetary Astrophysics (astro-ph.EP); Solar and Stellar Astrophysics (astro-ph.SR)
Cite as: arXiv:2401.16003 [astro-ph.EP] (or arXiv:2401.16003v1 [astro-ph.EP] for this version)
Submission history
From: Nicolas Cuello
[v1] Mon, 29 Jan 2024 09:47:45 UTC (8,756 KB)
https://arxiv.org/abs/2401.16003
Astrobiology

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) 🖖🏻