When you arrive, you take position in front of it, one hand grabbing the ladder. “This, my moon-bound mare, is what we came here in.” From her widening eyes and angling of her ears, you can tell her interest has gone from negligible to maximum in a fraction of a second. “Not just this, strictly speaking, but this is what we rode down to the surface. There was another part that would circle it high above, that carried all this here, and would carry this top half-” You jump up – the low gravity helping your altitude – to slap the side of the ascent module “-back home to Earth. The base would stay behind.”