This is the Web Edition of "A Trip Into Space", a Coimbra-based electronic book on space science. Both the texts and the photos are by courtesy of National Aeronautics and Space Administration.

Venus Fact Sheet

Venus/Earth Comparison


Bulk parameters

                                   Venus          Earth     Ratio (Venus/Earth)
Mass (1024 kg)                      4.8685         5.9736         0.815 
Volume (1010 km3)                  92.843        108.321          0.857
Equatorial radius (km)           6051.8         6378.1          0.949     
Polar radius (km)                  6051.8         6356.8          0.952
Volumetric mean radius (km)        6051.8         6371.0          0.950
Ellipticity (Flattening)            0.000          0.00335        0.0  
Mean density (kg/m3)               5204           5515            0.944 
Surface gravity (eq.) (m/s2)        8.87           9.78           0.907 
Escape velocity (km/s)             10.36          11.19           0.926
GM (x 106 km3/s2)                   0.3249         0.3986         0.815
Bond albedo                         0.72           0.385          1.87
Visual geometric albedo             0.65           0.367          1.77  
Visual magnitude V(1,0)            -4.40          -3.86             -
Solar irradiance (W/m2)            2613.9         1367.6          1.911
Black-body temperature (K)          238.9          247.3          0.966 
Topographic range (km)               15             20            0.750 
Moment of inertia (I/MR2)           0.33           0.3308         0.998
J2 (x 10-6)                         4.458       1082.63           0.004  


Orbital parameters

                                   Venus           Earth     Ratio (Venus/Earth)
Semimajor axis (106 km)           108.21          149.60          0.723   
Sidereal orbit period (days)      224.701         365.256         0.615
Tropical orbit period (days)      224.695         365.242         0.615 
Perihelion (106 km)               107.48          147.09          0.731       
Aphelion (106 km)                 108.94          152.10          0.716
Synodic period (days)             583.92            -               -
Mean orbital velocity (km/s)       35.02           29.78          1.176  
Max. orbital velocity (km/s)       35.26           30.29          1.164 
Min. orbital velocity (km/s)       34.79           29.29          1.188
Orbit inclination (deg)             3.39            0.00            -
Orbit eccentricity                  0.0067          0.0167        0.401   
Sidereal rotation period (hrs)  -5832.5            23.9345        243.7  
Obliquity to orbit (deg)          177.36           23.45         (0.113)  

Venus Observational Parameters

Discoverer:      Unknown
Discovery Date:  Prehistoric

Distance from Earth
        Minimum (106 km)            38.2
        Maximum (106 km)           261.0
Apparent diameter from Earth
        Maximum (seconds of arc)    66.0
        Minimum (seconds of arc)     9.7
Maximum visual magnitude            -4.4
Mean values at inferior conjunction with Earth
        Distance from Earth (106 km)         41.44    
        Apparent diameter (seconds of arc)   60.2

Venus Mean Orbital Elements (J2000)

Semimajor axis (AU)                  0.72333199  
Orbital eccentricity                 0.00677323   
Orbital inclination (deg)            3.39471   
Longitude of ascending node (deg)   76.68069  
Longitude of perihelion (deg)      131.53298  
Mean Longitude (deg)               181.97973

Venus Atmosphere


Surface Pressure: 92 bars  
Surface Density: ~65. kg/m3 
Scale height: 15.9 km
Average temperature: 737 K
Diurnal temperature range: ~0 
Wind speeds: 0.3 to 1.0 m/s (surface)
Mean molecular weight: 43.45 g/mole
Atmospheric composition (near surface, by volume): 
    Major:       96.5% Carbon Dioxide (CO2), 3.5% Nitrogen (N2) 
    Minor (ppm): Sulfur Dioxide (SO2) - 150; Argon (Ar) - 70; Water (H2O) - 20;
                 Carbon Monoxide (CO) - 17; Helium (He) - 12; Neon (Ne) - 7

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.

Last Update: 2004-Nov-27