Somehow I sent this in reply to Bob instead of the group. Sorry, Bob.
BUT one easy way to get gain is to use just a long coaxial gain cable. I think it takes about 22 feet of coaxial dipole elements at 2 meters to give about 6 dB of gain. So laying down 6 dB
gain segments on the rock of the moon is as easy as
unrolling a spool of cable. Unrolling 8 of these with the right spacing
could yield about 17 dB.
Of course this woiuld only point straight up, so it would need to be on a moon base in the middle of the earth facing side. But since there is a lot of interest in moon bases near the poles where there might be water, then a similar array of layed down coaxial cable arrays could be phased horizontally to point at earth. Actually, just about any direction can be obtained with the right spacing.
ONLY problem of course is there has to be someone with legs to roll out the cables.
How about, if the location is very near the pole, an array that extends up like a push-pole vertically from the craft, with tape measure type dipoles that spring out horizontally when the pole goes up? You might need a small rotator on the base of the pole then to make sure the dipoles point at Earth depending on the orientation of the craft when it lands, but that would only need to be turned once I believe, when it is deployed.
Jerry N0JY