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Table 1 General characteristics of Phobos

From: Surface environment of Phobos and Phobos simulant UTPS

Parameter Value References
Dimension 26.06 × 22.80 × 18.28 km Willner et al. (2014)
Mean radius 10.993 km Willner et al. (2014)
Mass 1.0668 ± 0.003 × 1016 kg Andert et al. (2010)
1.065 ± 0.015 × 1016 kg Pätzold et al. (2014)
1.0604 ± 0.0011 × 1016 kg Yang et al. (2019)
Volume 5742 ± 35 km3 Willner et al. (2014)
Surface area 1567.9 km2  
Mean density 1.860 ± 0.013 g/cm3 Willner et al. (2014)
1.846 ± 0.011 g/cm3 Yang et al. (2019)
Surface gravity 0.003–0.007 m/s2 Thomas (1993)
Escape velocity 11.39 m/s  
Rotation period 7 h 39 min 19.47 s Jacobson (2010)
Semi-major axis of the orbit 9375 km (2.76 Mars radii) Jacobson (2010)
Mean orbital velocity 2.138 km/s Jacobson (2010)
Equatorial rotation velocity 2.97 m/s  
Eccentricity 0.0151 Jacobson (2010)
Inclination 1.0847 deg to Mars’ equator Jacobson (2010)
1.0756 deg to local Laplace plane
26.04 deg to the ecliptic plane
Geometric albedo 0.071 Simonelli et al. (1998)
IR emissivity 0.98  
Thermal inertia 20–70 Jm−2 K−1 s−1/2 Lunine et al. (1982), Kührt et al. (1992)
Surface slope 0–40 degree Willner et al. (2014), Wang and Wu (2020)
Dust deposition rate 14–26 µm/year  
Dust electric charge 10–16 C/particle Senshu et al. (2015)
Small meteorite flux 10–16 g/cm2/s Grün et al. (1985), Divine (1993)
Meteorite impact velocity 8.5–15 km/s Divine (1993)
Internal thermal flux 0.0 W/m2  
Surface temperature 60–330 K @N ± 60° Kührt and Giese (1989)