burrowing 1 to 3 meters into the surface. One penetrator will be
targeted at the equatorial area of the near side (in the vicinity of the
Apollo 12 and 14 landing sites) and one at the equatorial far side.
After deploying the penetrators, the orbiter will move up to a 200 to
300 km near circular mapping orbit. Data will be stored in memory
in the penetrators and transmitted to the orbiter when it transits
over each penetrator every 15 days. 

The main body of the orbiter is a 120 cm diameter cylinder which is
111 cm in height, excluding the engine nozzle which protrudes
from the bottom of the craft. An orbit maneuvering system, S-band
antenna, and UHF-band antenna are situated on an end of the
cylinder, and a reaction control and another S-band antenna on the
other end. Three solar arrays extend perpendicular to the cylinder
axis, equally spaced around the body. A monochromatic mapping
camera with a resolution of 30 m is attached to the side of the
cylinder below one of the solar panels. It will be used to take
images near the terminator, where the lighting will enhance subtle
topographic features. The spacecraft is spin-stabilized. Attitude
and spin rate are controlled by an N2H4 monopropellant reaction
control system. Orbital maneuvering near the Moon is done using
a bipropellant (N2O4 and N2H4) engine.

The penetrators are missile-shaped cylinders, 90 cm in length
and 14 cm in diameter, and are attached to the sides of the
orbiter body between the solar arrays with their long axes
oriented in the same direction as the cylinder axis. The
penetrators have deorbit rocket engines which are fired after
separation. During free fall descent side-jets are used to orient
the penetrators. The deorbit motor and attitude controls are