Jupiter Fact Sheet

Jupiter/Earth Comparison

Bulk parameters

                                   Jupiter      Earth   Ratio (Jupiter/Earth)
Mass (10²⁴ kg)                      1,898.6     5.9736      317.83 
Volume (10¹⁰ km³)                 143,128     108.321      1321.33
Radius (1 bar level) (km)
    Equatorial                     71,492       6,378.1      11.209    
    Polar                          66,854       6,356.8      10.517
Volumetric mean radius (km)        69,911       6,371.0      10.973
Ellipticity                         0.06487     0.00335      19.36 
Mean density (kg/m³)                1,326       5,515         0.240 
Gravity (eq., 1 bar) (m/s²)        24.79        9.80          2.530 
Acceleration (eq., 1 bar) (m/s²)   23.12        9.78          2.364 
Escape velocity (km/s)             59.5        11.19          5.32
GM (x 10⁶ km³/s²)                 126.686       0.3986      317.8 
Bond albedo                         0.343       0.306         1.12
Visual geometric albedo             0.52        0.367         1.42  
Visual magnitude V(1,0)            -9.40       -3.86           -
Solar irradiance (W/m²)            50.50     1367.6           0.037
Black-body temperature (K)        110.0       254.3           0.433
Moment of inertia (I/MR²)           0.254       0.3308        0.768 
J₂ (x 10^-6)                        14,736    1082.63         13.611    
Number of natural satellites       63           1
Planetary ring system             Yes          No

Orbital parameters

                                   Jupiter      Earth   Ratio (Jupiter/Earth)
Semimajor axis (10⁶ km)             778.57      149.60        5.204   
Sidereal orbit period (days)      4,332.589     365.256      11.862   
Tropical orbit period (days)      4,330.595     365.242      11.857
Perihelion (10⁶ km)                 740.52      147.09        5.034      
Aphelion (10⁶ km)                   816.62      152.10        5.369
Synodic period (days)               398.88        -             -
Mean orbital velocity (km/s)         13.07       29.78        0.439    
Max. orbital velocity (km/s)         13.72       30.29        0.453        
Min. orbital velocity (km/s)         12.44       29.29        0.425       
Orbit inclination (deg)               1.304       0.000         -
Orbit eccentricity                    0.0489      0.0167      2.928
Sidereal rotation period (hours)      9.9250*    23.9345      0.415  
Length of day (hrs)                   9.9259     24.0000      0.414
Obliquity to orbit (deg)              3.13       23.45        0.133

* System III (1965.0) coordinates

Jupiter Observational Parameters

Discoverer:      Unknown
Discovery Date:  Prehistoric

Distance from Earth
        Minimum (10⁶ km)          588.5
        Maximum (10⁶ km)          968.1
Apparent diameter from Earth
        Maximum (seconds of arc)   50.1
        Minimum (seconds of arc)   29.8
Mean values at opposition from Earth
        Distance from Earth (10⁶ km)        628.76    
        Apparent diameter (seconds of arc)   46.9
        Apparent visual magnitude            -2.7      
Maximum apparent visual magnitude            -2.94

Jupiter Mean Orbital Elements (J2000)

Semimajor axis (AU)                  5.20336301  
Orbital eccentricity                 0.04839266   
Orbital inclination (deg)            1.30530  
Longitude of ascending node (deg)  100.55615   
Longitude of perihelion (deg)       14.75385   
Mean Longitude (deg)                34.40438

North Pole of Rotation

Right Ascension: 268.05 - 0.009T
Declination    :  64.49 + 0.003T
Reference Date : 12:00 UT 1 Jan 2000 (JD 2451545.0)
T = Julian centuries from reference date

Jovian Magnetosphere

Goddard Space Flight Center O4 Model

Dipole field strength: 4.28 gauss-Rj³
Dipole tilt to rotational axis: 9.6 degrees
Longitude of tilt: 201.7 degrees
Dipole offset (planet center to dipole center) distance: 0.131 Rj
Latitude/Longitude of offset vector: -8.0 degrees/148.57 degrees

Note: All latitudes/longitudes are given in Jovian System III (1965.0) coordinates.
Rj denotes Jovian radii, 71,398 km

Jovian Atmosphere

Surface Pressure: >>1000 bars  
Temperature at 1 bar: 165 K (-108 C)
Temperature at 0.1 bar: 112 K (-161 C)
Density at 1 bar: 0.16 kg/m³
Wind speeds
   Up to 150 m/s (<30 degrees latitude)
   Up to  40 m/s (>30 degrees latitude)
Scale height: 27 km
Mean molecular weight: 2.22 g/mole
Atmospheric composition (by volume, uncertainty in parentheses)
    Major:       Molecular hydrogen (H₂) - 89.8% (2.0%); Helium (He) - 10.2% (2.0%)
    Minor (ppm): Methane (CH₄) - 3000 (1000); Ammonia (NH₃) - 260 (40);
                 Hydrogen Deuteride (HD) - 28 (10); Ethane (C₂H₆) - 5.8 (1.5);
                 Water (H₂O) - 4 (varies with pressure)
    Aerosols:    Ammonia ice, water ice, ammonia hydrosulfide

If no sub- or superscripts appear on this page - for example, if the "Mass" is given in units of "(1024 kg)" - you may want to check the notes on the sub- and superscripts.

Notes on the factsheets - definitions of parameters, units, notes on sub- and superscripts, etc.

Jovian Satellite Fact Sheet

Jovian Rings Fact Sheet

Planetary Fact Table - metric units
Planetary Fact Table - U.S. units
Planetary Fact Table - Earth ratio

Jupiter Home Page
Directory to other Planetary Fact Sheets

Author/Curator:
Dr. David R. Williams, dave.williams@nasa.gov
NSSDC, Mail Code 690.1
NASA Goddard Space Flight Center
Greenbelt, MD 20771
+1-301-286-1258