Hi gb

I had forgotten about that page! Thanks for the link.

Some NEOs are easier to reach than others, and the mean waiting time for a Hohmann transfer launch window goes way up if their period is too close to Earth's.

It would be cool for so many reasons to have a refuelling base on the Moon, but I think NEOs provide the best bet for easily accessible volatiles. And some are on convenient orbits to be way-stations between Earth and Mars - Earth-Mars cyclers with insitu materials for construction/refuelling.

Duncan Steel has suggested that 1991 VG is artificial and non-terrestrial. Its orbit doesn't fit any known satellite or booster and it shows specular reflection consistent with worked metal. Perhaps it's the L3/4 alien probe that left orbit after Anthony Lawton's radio experiments in the 1970s? ;-)