LUNIK III: A Novel Approach to Modeling Soviet Spacecraft

The goal was simple – Build a football-size model of Russia's Automatic Interplanetary Station, aka LUNIK III, in a reasonable amount of detail.

LUNIK III was launched to the moon on October 4, 1959, exactly two years to the day after the Russians opened the Space Age with Sputnik I. Lunik I had flown past the moon into solar orbit. Lunik II had crashed into it. LUNIK III's task was to pass the moon, as LUNIK I had done, then photograph the far side for the first time in history. That would require some unique geometry.

LUNIK III was formed by its Soviet designers from four basic geometric shapes: a hemisphere, a cylinder, or drum, a geometric flange, and parabola. The dome part would come from a security camera's protective plastic cover. The parabola was taken from a camera flash unit. A cylinder drum was no problem. The flange though, would require lots of inventiveness along the way, and had some constraints:

• It contained pyramidal apex sections, angled at 110 degrees, instead of the usual 90.
• There were to be 12 sections altogether, spaced around the edge like hours on a clock.
• Each pyramid would be cut at an angle to fit with the next.
• Each would support a diamond-shaped solar cell assembly, with plates separating them.
• An outer ring of solar cells would complete the periphery.
• Finally, the flange assembly had to join the parabola to the cylinder drum.

Five individual rings of solar cells would surround the spacecraft.

Since the hemisphere, the cylinder, the flange, and the parabola could initially be fashioned separately, that allowed for simultaneous construction of all four sections. As they were each being formed, several alternate techniques were explored for joining these sections together in the final assembly. One technique emerged a clear winner – the use of JB Weld. JB Weld is a dark gray, epoxy-like mix sold for heavy-duty gluing requirements, and functions as its own unique “composite” material for this project.

Along the way, several varying techniques for making solar panels, or individual solar cells were explored. The information gained was stored away for future projects. The technique chosen for Lunik III was to use a mesh overlay, giving the illusion of hundreds of individual cells on a panel. The technique itself was simple. Begin with a slab of plastic, any thickness. Spray paint one side with gray primer, and while that paint is very tacky, overlay with a film of blue or purple metalflake. Blue looks more realistic, but purple was selected for its stark appearance on the finished model. On the outer flange ring, both sides needed painting, so plenty of drying time was allowed. Finally, the plastic wafer was covered in model railroad mesh to give the appearance of an entire panel of cells.

Another innovation for this model was the incorporation of a central longitudinal piece of PEX tubing, mounted to Quest fittings. This provided additional strength to the finished model, instead of relying solely on the periphery to provide robustness. The finished model weighs well over a 1 lb.