National Aeronautics and Space Administration Logo
Follow this link to skip to the main content NASA Banner
Solar System Exploration
Planets
SSE Home  >  Planets  >  Mars  >  Moons  >  Deimos  >  Facts & Figures 
Deimos: Facts & Figures
   Back to Mars   Overview   Gallery   Facts & Figures   News 
Discovered By
A. Hall
Date of Discovery
1877
Orbit Size Around Mars (semi-major axis)
Metric: 23,458 km
English: 14,576 miles
Periapsis (closest)
Metric: 23,453 km
Apoapsis (farthest)
Metric: 23,463 km
Sidereal Orbit Period (Length of Year)
1.2624 Earth days
Orbit Circumference
Metric: 147,390.96 km
Average Orbit Velocity
Metric: 4,864.8 km/h
Orbit Eccentricity
0.0002
Orbit Inclination
1.788 degrees
Mean Radius
Metric: 6.2 km
By Comparison: 7.5 x 6.1 x 5.2 km, tri-axial shape
Equatorial Circumference
Metric: 39.0 km
Volume
Metric: 998 km3
Mass
Metric: 1,476,188,406,600,740 kg
Scientific Notation: 1.4762 x 1015 kg
Density
Metric: 1.471 g/cm3
Surface Area
Metric: 483.05 km2
Surface Gravity
Metric: 0.003 m/s2
Escape Velocity
Metric: 20 km/h
English: 13 mph
Scientific Notation: 6 m/s
Rotation Period (Length of Day)
1.2624 Earth days
30.2976 hours
By Comparison: Synchronous with orbital period
Awards and Recognition   Solar System Exploration Roadmap   Contact Us   Site Map   Print This Page
NASA Official: Kristen Erickson
Advisory: Dr. James Green, Director of Planetary Science
Outreach Manager: Alice Wessen
Curator/Editor: Phil Davis
Science Writers: Samantha Harvey & Autumn Burdick
Producer: Greg Baerg
Webmaster: David Martin
> NASA Science Mission Directorate
> Budgets, Strategic Plans and Accountability Reports
> Equal Employment Opportunity Data
   Posted Pursuant to the No Fear Act
> Information-Dissemination Policies and Inventories
> Freedom of Information Act
> Privacy Policy & Important Notices
> Inspector General Hotline
> Office of the Inspector General
> NASA Communications Policy
> USA.gov
> ExpectMore.gov
> NASA Advisory Council
> Open Government at NASA
Last Updated: 24 Apr 2012