A more practical way to lift the orbit is probably to "capture an asteroid of suitable size and set it on a series of fly-bys, shuttling between near the Earth

A more practical way to lift the orbit is probably to "capture an asteroid of suitable size and set it on a series of fly-bys, shuttling between near the Earth and near Jupiter" https://www.quora.com/Would-it-be-theoretically-possible-to-slowly-enlarge-the-Earth-s-orbit-around-the-Sun-perhaps-to-counter-the-increased-energy-output-of-the-sun-in-a-billion-years https://www.quora.com/Would-it-be-theoretically-possible-to-...