SETI & Technosignatures

Improved Analysis of Clarke Exobelt Detectability

By Keith Cowing

Press Release

astro-ph.EP

September 23, 2019

Filed under SETI

Improved Analysis of Clarke Exobelt Detectability — Left: Satellite orbiting an Earth analog that is at the inner edge of the HZ for an M8 star. Without the star's influence, the satellite would be in a circular orbit at 5 planetary (Earth) radii (<em>R<sub>m</sub> = 5R<sub>p</sub></em>). The satellite orbits are shown in a reference frame centered on the planet (but not in the rotating reference frame). A red line connects the dots representing the satellite's position throughout the simulation. The dots' color gradually shifts from purple (start) to yellow (end) as time increments in the simulation. Right: Same, but with <em>R<sub>m</sub> = 6R<sub>p</sub></em>.

astro-ph.EP

We analyze the potential transit light curve effects due to a Clarke belt of satellites around an exoplanet.

Building on code and analysis from Korpela, Sallmen, & Leystra Greene (2015), we refine the transit analysis of Socas-Navarro (2018) by incorporating limb-darkening and taking an observer-centered approach to examining residuals. Wealso consider practical dynamical issues for exobelts, finding that synchronously orbiting belts are dynamically impossible around planets in the habitable zones of M stars, and determining the maximum quasi-stable belt size in these situations. Using simulations for both G and M stars, we conclude that to have an even marginally detectable impact on transit light curves, exobelts must be substantially denser than previous estimates.

We also estimate collision rates for the required satellite densities, finding they would present significant monitoring and guidance challenges. We conclude that detectable exobelts are likely to be rare, and have extremely low prospects for detection by transit monitoring from both current and upcoming missions

Shauna Sallmen, Eric J. Korpela, Kaisa Crawford-Taylor
(Submitted on 22 Sep 2019)
Comments: Submitted to The Astrophysical Journal. 16 pages including 5 figures
Subjects: Earth and Planetary Astrophysics (astro-ph.EP)
Cite as: arXiv:1909.10061 [astro-ph.EP] (or arXiv:1909.10061v1 [astro-ph.EP] for this version)
Submission history
From: Shauna Sallmen
[v1] Sun, 22 Sep 2019 18:23:52 UTC (2,708 KB)
https://arxiv.org/abs/1909.10061
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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