This chart shows the differences between Deimos and Mars. To change the planets/moons being compared, change one or more of the form fields at the bottom and click Refresh.

	Deimos	Mars
Discovered By	A. Hall	Known by the Ancients
Date of Discovery	1877	Unknown
Average Orbit Distance	23,458 km	227,943,824 km
Perihelion/Perigee (closest)	23,453 km	206,655,215 km
Aphelion/Apogee (farthest)	23,463 km	249,232,432 km
Equatorial Radius	6.2 km	3,389.5 km
Equatorial Circumference	39.0 km	21,296.9 km
Volume	998 km3	163,115,609,799 km3
Mass	1,476,188,406,600,740 kg	641,693,000,000,000,000,000,000 kg
Density	1.471 g/cm3	3.934 g/cm3
Surface Area	483.05 km2	144,371,391 km2
Equatorial Surface Gravity	0.003 m/s2	3.71 m/s2
Escape Velocity	20 km/h	18,108 km/h
Rotation Period (Length of Day)	1.2624 Earth days	1.026 sidereal days
Mean Orbit Velocity	4,864.8 km/h	86,677 km/h
Orbit Eccentricity	0.0002	0.0933941
Orbit Inclination to Ecliptic	1.788 degrees	1.85 degrees
Orbit Circumference	147,390.96 km	1,429,085,052 km