Impacts from outside our solar sytem?

[3488]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'><font color="#ff0000">I would agree with this for 2 reasons.&nbsp; First, a Jupiter type object barrelling through the inner solar system is extremely unlikely.&nbsp; Second, even if it did, it woul....... circumstances.---------------------------------------------------secondAttempt = tony873004 from the old forum.&nbsp; <br /> Posted by secondAttempt</font></DIV></p><p><font size="2"><strong>Hi tony,</strong></font></p><p><font size="2"><strong>I vaguely remember your handle & yes I agree with Wayne, it's great that you have returned.</strong></font></p><p><font size="2"><strong>Regarding rogue planets, I really think they exist & I think the reasons for my opinion as stated in my earlier post are scientifically justifiable, so yes they exist, just dunno how many.</strong></font></p><p><font size="2"><strong>I have a thing about Jupiter's moon Ganymede, i.e according to the cratering distrbution & evidence of renewed cryovolcanism & tectonics in a much more recent secondary sequence of events some 750 MYA - 1 GYA, suggests Ganymede temporarily entered a more eccentric orbit around Jupiter, out of the current & previous resonance with Io & Europa raising larger tides, reheating the interior (nothing as powerful as Io, but enough for cryovolcanism), causing further differentiation (Ganymede is the only body other than Earth showing evidence of a dual layered core, though recent MESSENGER passes suggest Mercury too), not to mention an active internally driven magnetosphere (the only know moon to have one. Europa's & Callisto's are induced by Jupiter's, Ganymede has it's own independent one).</strong></font></p><p><font size="2"><strong>Question is: What happened to cause Ganymede, which is a large & quite massive body in it's own right to take up a temporary more elliptical orbit around Jupiter before the tidal influences of the other Galileans, bought Ganymede back in resonance?&nbsp; <br /></strong></font></p><p><font size="2"><strong>Could this be some evidence of a passage of a massive body by the Jovian system & Ganymede happened to be on that side????</strong></font></p><p><font size="2"><strong>55 KM long & 17 KM wide, Sippur Sulcus on Ganymede. Cryovolcanic caldera & flow. Symptom of possible disruption from passing rogue planet, 750 MYA - 1 GYA???</strong></font><br /><img src="http://sitelife.space.com/ver1.0/Content/images/store/4/10/24287169-c201-456d-ba10-76e20ede8b84.Medium.jpg" alt="" /></p><p><font size="2"><strong>Andrew Brown.&nbsp;</strong></font></p> <div class="Discussion_UserSignature"> <p><font color="#000080">"I suddenly noticed an anomaly to the left of Io, just off the rim of that world. It was extremely large with respect to the overall size of Io and crescent shaped. It seemed unbelievable that something that big had not been visible before".</font> <em><strong><font color="#000000">Linda Morabito </font></strong><font color="#800000">on discovering that the Jupiter moon Io was volcanically active. Friday 9th March 1979.</font></em></p><p><font size="1" color="#000080">http://www.launchphotography.com/</font><br /><br /><font size="1" color="#000080">http://anthmartian.googlepages.com/thisislandearth</font></p><p><font size="1" color="#000080">http://web.me.com/meridianijournal</font></p> </div>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>and I see I forgot to give the link :&nbsp; http://www.orbitsimulator.com/gravity/articles/sedna.html <br />Posted by secondAttempt</DIV><br /><br />Oh fine, just what I needed...another open tab with more stuff to shove in my brain!!</p><p>Thanx </p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[secondAttempt]

<p><font size="2">Thank's for the welcome backs!!&nbsp; I've tried to return a few times, but there was always something wrong with the process (seemed like server error) that prevented it.&nbsp; Recently, it worked, but it locked me out of my old name (tells me wrong password, even after I reset the password), hence my new name: secondAttempt. </font></p><p><br /><font size="2"><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Regarding rogue planets, I really think they exist & I think the reasons for my opinion as stated in my earlier post are scientifically justifiable, so yes they exist, just dunno how many.<br /></DIV></font></p><p><font size="2">I agree with you.&nbsp; Rogue planets exist.&nbsp; I can't say definately, because none have been observed.&nbsp; But it makes sense that some sizeable stuff gets ejected during star system&nbsp;formation, and also during star death, and to a lesser degree, anywhere inbetween.&nbsp; The question, as you say, is just how many?&nbsp; If each star produces on average a few thousand quadrillion of them, then there should be be a few within eyesight of us right now.&nbsp; But if each produces only 10 (probably a better guess), then it's extremely likely that one has never passed through our solar system's planetary region, or ever will.</font></p><p><font size="2">Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Question is: What happened to cause Ganymede, which is a large & quite massive body in it's own right to take up a temporary more elliptical orbit around Jupiter before the tidal influences of the other Galileans, bought Ganymede back in resonance? </DIV></font></p><p><br /><font size="2">If a perturber was responsible, Ganymede being massive has nothing to do with it.&nbsp; Its mass will increase its inertia, but that's irrelavent.&nbsp;&nbsp; It's like Galileo's experiment where he drops a big rock and a small rock from the Tower if Piza.&nbsp; The big rock falls at the same rate as the small rock.&nbsp; Likewise, a perturbing object's gravity will accelerate a big rock and a small rock at the same rate, even if the small rock is a speck of dust, and the large rock is Ganymede.</font></p><p><font size="2"><br />It's probably not the tidal influences of of the other Galileans that would have re-circularized Ganymede's orbit.&nbsp; It would probably be the tidal interaction with Jupiter itself.</font></p><p><font size="2">But that's interesting stuff about Ganymede. I didn't know it had a period of recent cyovolcanism.&nbsp;&nbsp; If its orbit suddenly shifted, the only plausable explanation I can think of is that something&nbsp;massive passed near it.&nbsp; But is the perturber an exosolar object?&nbsp; I would guess not.&nbsp; The odds are just too slim that something exosolar not only passed through our solar system's planetary region, but that it passed close enough to the Jovian system to disrupt its inner moons.&nbsp; </font></p><p><font size="2">Something within our solar system could possibly do it.&nbsp; Since&nbsp;such an object&nbsp;must be in a Jupiter-crossing orbit to perturb Ganymede, its ultimate fate would be a collistion with Jupiter, or an ejection from our solar system.&nbsp; So it wouldn't be here today to serve as the smoking gun.&nbsp; </font></p><p><font size="2">The other explanation I can think of is that something other than a shift in orbit caused the renewed cryovolcanism.&nbsp; Perhaps Ganymede got hit with something too small to perturb its orbit, but large enough to melt it and add lots of heat to its interior.&nbsp; Ganymede does sit next to Jupiter, the solar system's vacuum cleaner.</font></p><p><font size="2">But if this renewed cycovolvanism&nbsp; was due to an orbit change, it wouldn't take a very large change.&nbsp;&nbsp;&nbsp; The Galilean moons don't experience tides like Earth does.&nbsp; They are tidally locked to Jupiter, so their tides are completely dependent on the eccentricity of their orbits.&nbsp; Io currently has volcanoes and its orbit is almost circular.&nbsp; Just a small change in Ganymede's eccentricity should significantly boost its tidal heating.</font></p>

 

[MeteorWayne]

<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Posted by secondAttempt</DIV><br /><br />Tony, just FYI, if you send an email to Community [at] imaginova {dot) com, dh can help you with getting your original handle restored. Unless you like SecondAttempt </p><p>MW</p> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>