The gaps are not actual "gaps"--if you were to see a plot of all the orbits of the asteroids, you'd only see an endless tangle of circles and ellipses. It only emerges in statistical analysis of the average distances of asteroids in the belt.
stargrazer - I am looking at a diagram of the asteroid belts with the kirkwood gaps.<br /><br />I have not progressed to scanning diagrams and then posting them.<br /><br />It is in 2-D, not 3-D. I believe this is not much of a problem, since most asteroids orbit near the solar system eccliptic.<br /><br />The biggest gap by far is the outermost one. In that latter case the gap is bigger than the two belts. The outermost belt is thin, the belt inside this large gap is quite wide.<br /><br />The next to outermost gap is the next widest gap. The rest of the gaps are relatively narrow, while the asteroid belts are much larger.<br /><br />The distance between the outermost asteroid belt and Jupiter is much larger than the distance between the innermost asteroid belt and Mars.<br />I suppose the mechanism may be related to rings around planets - perhaps.<br /><br />There are many aberrant asteroids that do not follow typical asteroid belt paths.<br /><br />Hidalgo orbits from the innermost belt almost to Saturn's orbital path!<br /><br />The trojans are on Jupiter's orbital path.<br /><br />1983 TB and Icarus orbit from beyond Mars to very close to the sun - which means they cross earth's orbital path.<br /><br />Apollo, Innisfree and Lost City also cross earth's orbital path. So does Pribram.<br /><br />The very large asteroid Chiron is much further out, beyond Saturn's orbit!<br /><br />BTW - the cause of kirkwood gaps in asteroid belts may be similar to 'gaps' in Saturn's rings.<br /><br />The problem is: that cause (maintenance) is debated! As are the origins.<br /><br />Is it leftover from original solar system (or, in Saturn's case: planetary) accretion, or is it leftovers from the breakup of a satellite(s) - for the asteroids: of the sun; for Saturn's rings: of Saturn.<br /><br />Or some of both!
zavvy- Thanks for the links. I won't study all 6,000+ of them!<br /><br />I especially liked this one:<br /><br />http://ssd.jpl.nasa.gov/a_histo.html<br /><br />thalion - the graph in the above link sure seems to describe actual gaps!<br /><br />Then again, Saturn's ring gaps are not empty either.