Hugest gas giant planets may have a terrestrial-sized moon?

[silylene old]

There is an interesting article in Astrobiology Magazine which cites a recent <i>Nature</i> article about sattelite growth simulations which comes to a conclusion that the mass of a gas giant planets' satellites is always about 1/10,000 the mass of the gas giant planet itself. And furthermore, the total mass of the solar system gas giant moon systems to the mass of thier parent planet is always about 1/10,000.<br /><br />So let me take this proposition from the above article a step further. Let me propose the next proposition: Only the hugest gas giant planets can have an earth-sized moon, if one follows the 1/10,000 rule.<br /><br />If this is true, it greatly limits the chance of finding moon systems which can support life (or at least advanced life) in the universe. Why? It limits the number of gas giant planets which are large enough to have a moon as big as the earth.<br /><br />Perhaps one of our SDC members can further define what is the minimum sized gas giant which can support a moon large enough to hold an earth-sized moon, what the narrowed population ratio of gas giants large enough to support terrestrial-sized moons might be. This factor could be important if one is trying to guesstimate the potential of finding advanced extraterrestrial civilization somewhere else in our galaxy. <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[vonster]

immediate problems with this that i see (correct me if im wrong, but):<br /><br />1 - we've only detected less than 150 gas giant planets outside of our system ... out of trillions and trillions of systems in the universe.<br /><br />and many (most?) of those are "hot jupiters" that are very, very close to the host star - because this reflects the limiations of our detection methods so far.<br /><br />so to say that "mass of a gas giant sattelite is <b>always</b> anything is reaching.<br /><br /><br /><br />2 - To further make the speculation of sattelite size based on "growth simulations" is also reaching<br /><br />How do you simulate growth when we're not really sure of the rules of planet formation, let alone the fact that we have multiple theories about sattelites can come to be around planets<br /><br />- capture<br />- formation from the parent planet<br />- formation in lagrange orbits and subsequent capture.<br />- etc?<br /><br />this uncertainty is multiplied by the fact that we are suprised to find as many hot jupiters as we have ... its placing some doubt on current accretion theories of planet formation altogether.<br /><br />no, i really dont understand how they are reaching these conclusions at all<br /><br /><br />.<br /><br />

 

[dragon04]

One thing I noticed was that the "formula" took into account the total mass of all the satellites. Seems a bit arbitrary to me.<br /><br />There are so many factors involved. How much more massive would Jovian or Saturnian satellites potentially be if they were more sunward assuming more available mass to be accreted?<br /><br />I'll not deny that it's a potential model for "our" discrete Solar System, but I don't know that the formula is neccessarily ubiquitous.<br /><br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>