> capture it in Earth orbit as a lower moon. If it's below geostationary orbit, tidal forces will eventually bring it down. This is happening with Mars' moons

> capture it in Earth orbit as a lower moon. If it's below geostationary orbit, tidal forces will eventually bring it down. This is happening with Mars' moons for example, which are probably (naturally) captured asteroids. You would be committing the far future inhabitants of Earth to the impact, if they didn't have the means to boost the orbit.