The shot is totally within the capabilities of a 200 mm Schmidt–Cassegrain in good seeing, which is not very bulky and could sit comfortably on a medium-to-large size tripod.

The theoretical linear resolving power of that aperture at 5 km is 12 mm. But in practice it will be several times worse.

This is all napkin-based math, I've no clue what optics were used for the shot. Might have been a compact 150 mm apochromat refractor - still capable of enough theoretical resolution, and possibly a more popular option (though more expensive) in practice.