Planets Fact Sheet

Mercury

Mass: 0.3302 x 10

kg
Volume: 6.083 x 10

Average radius: 2439.7 km Average diameter: 4879.4 km Mean density: 5.427 g/cm

Escape velocity: 4.3 km/s Surface gravity: 3.7 m/s

Visual magnitude: -0.42 Natural satellites: 0 Rings? - No Semimajor axis: 57,910,000 km Orbit period: 87.969 days Perihelion: 46,000,000 km Aphelion: 69,820,000 km
Mean orbital velocity: 47.87 km/s Maximum orbital velocity: 58.98 km/s Minimum orbital velocity: 38.86 km/s Orbit inclination: 7.00° Orbit

eccentricity: 0.2056 Sidereal rotation period: 1407.6 hours
Length of day: 4222.6 hours Discovery: Known since prehistoric times Minimum distance from Earth: 77,300,000 km Maximum distance from Earth: 221,900,000 km Maximum apparent diameter from Earth: 13 arc seconds Minimum apparent diameter from Earth: 4.5 arc seconds Maximum visual magnitude: -1.9

Venus

Mass: 4.8685 x 10

kg
Volume: 92.843 x 10

Average radius: 6051.8 km Average diameter: 12103.6 km Mean density: 5.243 g/cm

Escape velocity: 10.36 km/s Surface gravity: 8.87 m/s

Visual magnitude: -4.40 Natural satellites: 0 Rings? - No Semimajor axis: 108,210,000 km Orbit period: 224.701 days Perihelion: 107,480,000 km Aphelion: 108,940,000 km
Mean orbital velocity: 35.02 km/s Maximum orbital velocity: 35.26 km/s Minimum orbital velocity: 34.79 km/s Orbit inclination: 3.39° Orbit eccentricity: 0.0067 Sidereal rotation period: 5832.5 hours
Length of day: 2802.0 hours Discovery: Known since prehistoric times Minimum distance from Earth: 38,200,000 km Maximum distance from Earth: 261,000,000 km Maximum apparent diameter from Earth: 66.0 arc seconds Minimum apparent diameter from Earth: 9.7 arc seconds Maximum visual magnitude: -4.6

Earth

Mass: 5.9736 x 10

kg
Volume: 108.321 x 10

Average radius: 6,371.0 km Average diameter: 12,742 km Mean density: 5.515 g/cm

Escape velocity: 11.186 km/s Surface gravity: 9.798 m/s

Visual magnitude: -3.86 Natural satellites: 1 Rings? - No Semimajor axis: 149,600,000 km Orbit period: 365.256 days Perihelion: 147,090,000 km Aphelion: 152,100,000 km
Mean orbital velocity: 29.78 km/s Maximum orbital velocity: 30.29 km/s Minimum orbital velocity: 29.29 km/s Orbit inclination: 0.00° Orbit eccentricity: 0.0167 Sidereal rotation period: 23.9345 hours
Length of day: 24.0000 hours Axial tilt: 23.45°

Mars

Mass: 0.64185 x 10

kg
Volume: 16.318 x 10

Average radius: 3,389.5 km Average diameter: 6,779 km Mean density: 3.933 g/cm

Escape velocity: 5.03 km/s Surface gravity: 3.71 m/s

Visual magnitude: -1.52 Natural satellites: 2 Rings? - No Semimajor axis: 227,920,000 km Orbit period: 686.980 days Perihelion: 206,620,000 km Aphelion: 249,230,000 km
Mean orbital velocity: 24.13 km/s Orbit inclination: 1.850° Orbit eccentricity: 0.0935 Sidereal rotation period: 24.6229 hours
Length of day: 24.6597 hours Axial tilt: 25.19 ° Discovery: Known since prehistoric times Minimum distance from Earth: 55,700,000 km Maximum distance from Earth: 401,300,000 km Maximum apparent diameter from Earth: 25.1 arc seconds Minimum apparent diameter from Earth: 3.5 arc seconds Maximum visual magnitude: -2.91

Jupiter

Mass: 1,898.6 x 10

kg
Volume: 143,128 x 10

Average radius: 69,911 km Average diameter: 139,822 km Mean density: 1.326 g/cm

Escape velocity: 59.5 km/s Surface gravity: 24.79 m/s

Natural satellites: 63 Rings? - Yes Semimajor axis: 778,570,000 km Orbit period: 4,332.589 days Perihelion: 740,520,000 km Aphelion: 816,620,000 km
Mean orbital velocity: 13.07 km/s Orbit inclination: 1.304° Orbit eccentricity: 0.0489 Sidereal rotation period: 9.9250 hours
Length of day: 9.9259 hours Axial tilt: 3.13° Discovery: Known since prehistoric times Minimum distance from Earth: 588,500,000 km Maximum distance from Earth: 968,100,000 km Maximum apparent diameter from Earth: 50.1 arc seconds Minimum apparent diameter from Earth: 29.8 arc seconds Maximum visual magnitude: -2.94

Saturn

Mass: 568.46 x 10

kg
Volume: 82,713 x 10

Average radius: 58,232 km Average diameter: 116,464 km Mean density: 0.687 g/cm

Escape velocity: 35.5 km/s Surface gravity: 10.44 m/s

Natural satellites: 60 Rings? - Yes Semimajor axis: 1,433,530,000 km Orbit period: 10,759.22 days Perihelion: 1,352,550,000 km Aphelion: 1,514,500,000 km
Mean orbital velocity: 9.69 km/s Orbit inclination: 2.485° Orbit eccentricity: 0.0565 Sidereal rotation period: 10.656 hours
Length of day: 10.656 hours Axial tilt: 26.73° Discovery: Known since prehistoric times Minimum distance from Earth: 1,195,500,000 km Maximum distance from Earth: 1,658,500,000 km Maximum apparent diameter from Earth: 20.1 arc seconds Minimum apparent diameter from Earth: 14.5 arc seconds Maximum visual magnitude: 0.43

Uranus

Mass: 86.832 x 10

kg
Volume: 6,833 x 10

Average radius: 25,362 km Average diameter: 50,724 km Mean density: 1.270 g/cm

Escape velocity: 21.3 km/s Surface gravity: 8.87 m/s

Natural satellites: 27 Rings? - Yes Semimajor axis: 2,872,460,000 km Orbit period: 30,685.4 days Perihelion: 2,741,300,000 km Aphelion: 3,003,620,000 km
Mean orbital velocity: 6.81 km/s Orbit inclination: 0.772° Orbit eccentricity: 0.0457 Sidereal rotation period: 17.24 hours
Length of day: 17.24 hours Axial tilt: 97.77° Discovery: 13 March 1781 Minimum distance from Earth: 2,581,900,000 km Maximum distance from Earth: 3,157,300,000 km Maximum apparent diameter from Earth: 4.1 arc seconds Minimum apparent diameter from Earth: 3.3 arc seconds Maximum visual magnitude: 5.32

Neptune

Mass: 102.43 x 10

kg
Volume: 6,254 x 10

Average radius: 24,622 km Average diameter: 49,244 km Mean density: 1.638 g/cm

Escape velocity: 23.5 km/s Surface gravity: 11.15 m/s

Natural satellites: 13 Rings? - Yes Semimajor axis: 4,495,060,000 km Orbit period: 60,189 days Perihelion: 4,444,450,000 km Aphelion: 4,545,670,000 km
Mean orbital velocity: 5.43 km/s Orbit inclination: 1.769° Orbit eccentricity: 0.0113 Sidereal rotation period: 16.11 hours
Length of day: 16.11 hours Axial tilt: 28.32° Discovery: 23 September 1846 Minimum distance from Earth: 4,305,900,000 km Maximum distance from Earth: 4,687,300,000 km Maximum apparent diameter from Earth: 2.4 arc seconds Minimum apparent diameter from Earth: 2.2 arc seconds Maximum visual magnitude: 7.78

We've written many articles about the Solar System. Here's an article about how many

moons there are in the Solar System

, and here's an article about the

formation of the Solar System

If you'd like more info on the Solar System, check out

NASA's Planetary Fact Sheet

We've recorded several episodes of Astronomy Cast about the Solar System. Start here,

Episode 49: Mercury