Computed Physical Properties, Orbital Architecture, and ‎Dynamical Assessment of the TOI-5624 Multiplanetary ‎‎System

Bijan Nikouravan

doi:10.14331/ijfps.2026.330182

Authors

Bijan Nikouravan Department of Physics and Astrophysics, VaP. C, Islamic Azad University, Varamin, Iran Author

DOI:

https://doi.org/10.14331/ijfps.2026.330182

Keywords:

TOI-5624‎, exoplanets, multiplanetary systems, mutual Hill radius, equilibrium temperature

Abstract

The characterization of compact multiplanetary systems provides important insights into ‎planetary structure, orbital architecture, irradiation environments, and long-term ‎dynamical stability. In this work, the newly confirmed TOI-5624 system is investigated as a ‎five-planet system composed of TOI-5624 b, c, d, e, and f. The analysis is based on ‎observational data from the NASA Exoplanet Archive, combined with a reproducible ‎Python-based computational framework. A set of physical, orbital, thermal, and first-order ‎dynamical parameters is examined, including semi-major axis, orbital period, planetary ‎mass and radius, bulk density, equilibrium temperature, stellar flux, surface gravity, escape ‎velocity, period ratios between successive planets, and mutual Hill separations. Semi-‎major axes are independently calculated using Kepler’s third law and compared with ‎archive values, showing excellent agreement with differences below approximately 0.11 ‎percent. The results indicate that TOI-5624 is a compact multiplanetary system with ‎planets distributed between approximately 0.042 AU and 0.237 AU. The orbital period ‎ratios between successive planets are approximately 2.326, 1.741, 1.565, and 2.111, ‎suggesting a non-resonant but dynamically ordered architecture with near-‎commensurabilities. The mutual Hill separation analysis shows that all adjacent planet ‎pairs exceed both the classical two-planet Hill-stability limit of 2√3 and the conservative ‎empirical spacing threshold of Δ=10, indicating that the nominal system architecture is ‎well separated against immediate close encounters at the first-order level. The equilibrium ‎temperatures range from about 478.5 K to 1136 K, while the incident stellar flux spans from ‎approximately 8.7 to more than 275 times the Earth’s flux, indicating a strongly irradiated ‎system with no planet in an Earth-like habitable environment. This study provides a ‎consistent computational characterization of the TOI-5624 system and demonstrates a ‎reproducible first-order framework for examining the physical properties, irradiation ‎environment, orbital architecture, and dynamical spacing of newly confirmed compact ‎multiplanetary systems.‎

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Author Biography

Bijan Nikouravan, Department of Physics and Astrophysics, VaP. C, Islamic Azad University, Varamin, Iran

https://orcid.org/0000-0003-4308-1632

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