Black-Body Temperature

442.5 K

Bond Albedo

0.119

Ellipticity

0.0000

Equatorial Radius

2439.7 km

Escape Velocity

4.3 km s⁻¹

GM

0.02203 × 10⁶ km 3 s⁻²

Mass

0.3302 × 10²⁴ kg

Mean Density

5427 kg m⁻³

Moment of Inertia

0.33 I MR⁻²

Polar Radius

2439.7 km

Solar Irradiance

9126.6 W m⁻²

Surface Gravity

3.70 m s⁻²

Visual Geometric Albedo

0.106

Visual Magnitude

−0.42

Volume

6.083 × 10¹⁰ km³

Volumetric Mean Radius

2439.7 km

Aphelion

Length of Day

4222.6 hours

Maximum Orbital Velocity

58.98 km s⁻¹

Mean Orbital Velocity

47.87 km s⁻¹

Minimum Orbital Velocity

38.86 km s⁻¹

Obliquity to Orbit

0.01

Orbital Eccentricity

0.2056

Orbital Inclination

7.00 °

Perihelion

46.00 × 10⁶ km

Semimajor Axis

57.91 × 10⁶ km

Sidereal Orbit Period

87.969 days

Sidereal Rotation Period

1407.6 hours

Synodic Period

115.88 days

Tropical Orbit Period

87.968 days

Longitude of Ascending Node

48.33167°

Longitude of Perihelion

77.45645°

Mean Longitude

252.25084°

Orbital Eccentricity

0.20563069

Orbital Inclination

7.00487°

Semimajor Axis

0.38709893 AU

Dipole Field Strength

0.0033 gauss−Rh³ [*]

Dipole Tilt to Rotational Axis

169°

Longitude of Tilt

285° (from Mercury I flyby)
115° (from Mercury III flyby)

R_h = Mercurian Radii (2439.7 km)

Apparent Magnitude from Opposition

−1.9

Maximum Apparent Diameter from Earth

13 arc seconds

Maximum Distance from Earth

221.9 × 10⁶ km

Minimum Apparent Diameter from Earth

4.5 arc seconds

Minimum Distance from Earth

77.3 × 10⁶ km

Mercury has no known satellites