Table 1:

Quantities for Phobos and Deimos

		Phobos	Deimos
Dimensions	2ab, 2bb, 2cb	27 × 22 × 18 km	15 × 12.2 × 11 km
Body axis ratios	(bb/ab, cb/ab)	(0.82,0.67)	(0.82,0.73)
Mean Radius	R	11.2667 km	6.2 km
Mass	M	1.0659 × 1016 kg	1.4762 × 1015 kg
Mass ratio	MMars/M	6.0 × 107	4.3 × 108
Eccentricity	e	0.0151	0.00033
Semi-major axis	a	2.76RMars	6.91RMars
Orbital period	$P=\frac{2\pi }{\omega }$	0.3189 day	1.263 day
Gravitational timescale	$t_g$	1555 s	1418 s
Spin	$\omega t_g$	0.32	0.09
Surface rotational velocity	ωR	2.5 m/s	0.36 m/s
Semi-Major axis/Radius	a/R	830.3	3777.6
Mars spin	${\omega }_{\text{Mars }}{t}_q$	0.10	0.11
Radius ratio	RMars/R	300.8	546.7
Despin time	tdespin	3000 yr	4 × 105 yr
Eccentricity damping time	tedamp	0.4 × 109 yr	2 × 1012 yr
Asphericity parameter	α	0.82	0.65
Dissipation parameter	Kd	10−7	10−9
		Mars
Mars Radius	RMars	3389.5 km
Mars Mass	MMars	6.4171 × 1023 kg
Mars Rotation period	PMars	1.025957 day
Synchron. semi-maj. axis	async	6RMars
Moon Mass ratio	MPhobos/MDeimos	7.2

Orbital periods are sidereal. The gravitational time t_g is defined in Equation 9. Mars’ Love number and tidal dissipation factor are those measured by Bills et al. (2005). Despin and eccentricity damping times and K_d are estimated with μQ = 10¹¹ Pa, see section 1.1.