Descent Stage Layout Notes

The current design of the descent stage involves 6 cylindrical hydrogen tanks surrounding 1 spherical oxygen tank.

Hydrogen tank radius (x6)	25.84 inches
Oxygen tank radius	38 inches
Tank length	78 inches (overall, not just constant section)

The tank structure is sized to fit inside the dynamic envelope of a Titan IV booster (15 feet diameter). The tanks are about 13.5 feet diameter, plus structure, launch integration, etc.

This is surrounded with a hexagonal cage of structural members, although the surrounding hydrogen tanks offer a lot of structural rigidity. The laboratory deployment mechanism is hinged at the last major structural member, at the base of the tanks.

You probably wouldn't really see the tanks. We'd cover the whole tank assembly with crinkly gold foil to reflect sunlight away from the cryogenics. So the propulsion structure would wind up looking a bit like the base of the lunar module.

The design showing 6 landing gear, continuing the hexagonal symmetry, is tentative.