Much like the Lunar Module Ascent vehicle, the LK Lander Core is a part of the LK lander used after landing (in the case of Mission 21, on RED). This is the Russian version of the American lander. It can be launched together with LOK Lander Legs on an N1 rocket. It has its own fuel tank and shares thruster propellant/fuel with the LK Lander Legs prior to separation.
- During ascent, immediately after separation from the LK Lander Legs, this module temporarily enters a pre-programmed "auto-pilot" routine, which places it into a stable orbit.
- When maneuvering by itself in the launch stage, it can gain tremendous speeds using the main engine. This is probably because this engine is powerful enough to handle the additional mass of the LK Lander Legs while they are still connected, as well as having to overcome the gravity of the planet/moon.
- This was to be launched with the Soviet N1 rocket, but that rocket was never successfully used only bearing 4 launches to its name, with all of them failing.
- It was designed to carry 1 cosmonaut, and there were also plans make it a 2 man lander.
- What appears to be a cosmonaut's helmet in a window is actually just a rather unusually shaped observation port.
- The LK Lander was significantly smaller than its American lander counterpart.