Preventing Planetoid Collisions
How strongly do small outer planetoids (i.e., planets, moons, asteroids, comets) tend to move inward below the orbits of larger ones?
What formulae will tell us what these forces are and their timelines?
When will the following planetoids approach these orbits?
Mars to Earth's orbit?
Asteroids to Earth's orbit?
Saturn to Jupiter's?
Uranus and Neptune to Saturn's?
Pluto and Kuipers (i.e. Kuiper belt objects) to Neptune's?
What can be done to stabilize planetoidal orbits?
Can small ones be safely moved inward past larger ones?
Could their orbits be made highly elliptical and extra-ecliptical to get them past large ones, then be circularized?
What could ellipsize and circularize orbits and put them out of the ecliptic during passage?
Could asteroids be gathered together to make them larger?
Won't any collection of planetoids more than 200 miles in diameter condense into one body?
Could they be gathered together on Mars or Jupiter?
Or is it better to have lots of small planetoids where they are, for research, resources, inhabitation etc?
Could Mars be safely moved into Jupiter or into an outer orbit there?
Making Planetoids Habitable
What would be need to make Mars habitable?
Could Venus be made habitable by moving icy asteroids onto it?