Also had wondered why in some regards, Jupiter, Saturn, Uranus, and Neptune moon systems have similarities, like<br /><br />*rings of varying granduer<br /><br />*inner irregular small satellites (like Amalthea, Pan, etc.)<br /><br />*'regular' satellite zone <br /><br />* outer captured asteroidal (presumably) moons<br /><br />and differences, like<br /><br />*why did Jupiter get 4 big ones, Saturn one, Uranus none and Neptune has a big one in a freak retrograde orbit<br /><br />*Jupiter, Saturn, and Neptune have fairly similar ring systems, and then there's Saturn<br /><br />*Saturn, and Uranus get small size inner satellites like Ariel and Enceladus, Jupiter none and did Triton 'mess up' Neptune"s?<br /><br />*Iapetus has so many weird characteristics as to put it in a class by itself<br /><br />Sorry if this sounds so far off topic, but wouldn't you have suspected maybe some trending characteristics of satellites of outer solar system to be carryied over to inner solar system? Earth's moon always seemed freakishly out of place till Charon turned up. Mars has two close inner satellites I strongly suspect would look like outer asteroidal satellites of Jupiter, Saturn, Uranus, and Neptune, but what are they doing there? <br />Recall Comet Kohoutek was believed to have enormous nucleus (for a comet). Over billions of years would impacts of this class of object have demolished any possible satellite of Mercury? (comets going as fast as they ever go when they do perihelion in Mercury's vicinity )<br /><br />We probably aren't going to learn the 'big picture' about satellites until we receive our copy of Encyclopedia Galactica or write our own version. <div class="Discussion_UserSignature"> <p><font color="#ff0000"><strong>TPTB went to Dallas and all I got was Plucked !!</strong></font></p><p><font color="#339966"><strong>So many people, so few recipes !!</strong></font></p><p><font color="#0000ff"><strong>Let's clean up this stinkhole !!</strong></font> </p> </div>