Jupiter Fact Sheet

Jupiter/Earth Comparison

Bulk parameters

	Jupiter	Earth	Ratio (Jupiter/Earth)
Mass (10²⁴ kg)	1,898.19	5.9724	317.83
Volume (10¹⁰ km³)	143,128	108.321	1321.33
Equatorial radius (1 bar level) (km)	71,492	6,378.1	11.209
Polar radius (km)	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	5,514	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)	126.687	0.39860	317.83
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)	50.26	1361.0	0.037
Black-body temperature (K)	109.9	254.0	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	67	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)	13.06	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 (hrs)	9.9250*	23.9345	0.415
Length of day (hrs)	9.9259	24.0000	0.414
Obliquity to orbit (deg)	3.13	23.44	0.134
Inclination of equator (deg)	3.13	23.44	0.134

* 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: 268.057 - 0.006T
Declination    :  64.495 + 0.002T
Reference Date : 12:00 UT 1 Jan 2000 (JD 2451545.0)
T = Julian centuries from reference date

Jovian Magnetosphere

Model GSFC-O₆

Dipole field strength: 4.30 Gauss-Rj³
Dipole tilt to rotational axis: 9.4 degrees
Longitude of tilt: 200.1 degrees
Dipole offset: 0.119 Rj
Surface (1 Rj) field strength: 4.0 - 13.0 Gauss

Rj denotes Jovian model radius, defined here to be 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 
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

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
NSSDCA, Mail Code 690.1
NASA Goddard Space Flight Center
Greenbelt, MD 20771
+1-301-286-1258