ZX81 Lunar Lander

Guide the Lunar Excursion Module down to the landing zone safely. The landing zone is marked by five inverse video  L's. To complete a successful landing you must have zero forward velocity, and an altitude rate of no more than 1. The right hand portion of the screen has a semi authentic Apollo Guidance Computer readout - which is set to the PROG 66, VERB 6, NOUN 60 - these are the same as in the real Apollo mission.

PROG 66 is the program  ran when in the "terminal descent stage" of the landing

VERB 06 means display values

NOUN 60 means terminal descent monitor

The three numbers below that are "Forward Velocity", "Altitude Rate", and "Altitude"

This is a real time lunar landing game, none of the old "enter a thrust value, then wait to see the new calculated positions"