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Body  μ (km^{3}s^{−2}) 

Sun  132,712,440,018(8)^{[1]} 
Mercury  22,032 
Venus  324,859 
Earth  398,600.4418(9) 
Moon  4,902.7779 
Mars  42,828 
Ceres  63.1(3)^{[2]}^{[3]} 
Jupiter  126,686,534 
Saturn  37,931,187 
Uranus  5,793,939(13)^{[4]} 
Neptune  6,836,529 
Pluto  871(5)^{[5]} 
Eris  1,108(13)^{[6]} 
In celestial mechanics the standard gravitational parameter μ of a celestial body is the product of the gravitational constant G and the mass M of the body.
For several objects in the solar system, the value of μ is known to greater accuracy than G or M. The SI units of the standard gravitational parameter are m^{3}s^{−2}.
Contents 
Under standard assumptions in astrodynamics we have:
where m is the mass of the orbiting body, M is the mass of the central body, and G is the standard gravitational parameter of the larger body.
For all circular orbits around a given central body:
where r is the orbit radius, v is the orbital speed, ω is the angular speed, and T is the orbital period.
The last equality has a very simple generalization to elliptic orbits:
where a is the semimajor axis. See Kepler's third law.
For all parabolic trajectories rv^{2} is constant and equal to 2μ. For elliptic and hyperbolic orbits μ = 2aε, where ε is the specific orbital energy.
In the more general case where the bodies need not be a large one and a small one (the twobody problem), we define:
Then:
Note that the reduced mass is also denoted by .
The value for the Earth is called the geocentric gravitational constant and equals 398,600.4418±0.0008 km^{3}s^{−2}. Thus the uncertainty is 1 to 500,000,000, much smaller than the uncertainties in G and M separately (1 to 7,000 each).
The value for the Sun is called the heliocentric gravitational constant and equals 1.32712440018×10^{20} m^{3}s^{−2}.

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