definition of Wikipedia
Advertizing ▼
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}.

sensagent's content
Dictionary and translator for handheld
New : sensagent is now available on your handheld
Advertising ▼
Webmaster Solution
Alexandria
A windows (popinto) of information (fullcontent of Sensagent) triggered by doubleclicking any word on your webpage. Give contextual explanation and translation from your sites !
SensagentBox
With a SensagentBox, visitors to your site can access reliable information on over 5 million pages provided by Sensagent.com. Choose the design that fits your site.
Business solution
Improve your site content
Add new content to your site from Sensagent by XML.
Crawl products or adds
Get XML access to reach the best products.
Index images and define metadata
Get XML access to fix the meaning of your metadata.
Please, email us to describe your idea.
Lettris
Lettris is a curious tetrisclone game where all the bricks have the same square shape but different content. Each square carries a letter. To make squares disappear and save space for other squares you have to assemble English words (left, right, up, down) from the falling squares.
boggle
Boggle gives you 3 minutes to find as many words (3 letters or more) as you can in a grid of 16 letters. You can also try the grid of 16 letters. Letters must be adjacent and longer words score better. See if you can get into the grid Hall of Fame !
English dictionary
Main references
Most English definitions are provided by WordNet .
English thesaurus is mainly derived from The Integral Dictionary (TID).
English Encyclopedia is licensed by Wikipedia (GNU).
Copyrights
The wordgames anagrams, crossword, Lettris and Boggle are provided by Memodata.
The web service Alexandria is granted from Memodata for the Ebay search.
The SensagentBox are offered by sensAgent.
Translation
Change the target language to find translations.
Tips: browse the semantic fields (see From ideas to words) in two languages to learn more.
last searches on the dictionary :
computed in 0.046s