Snowman Rocket

Space flight is a long journey. Only the initial small part of it is through the dense atmosphere where the aerodynamic design matters. The rest of the journey is in vacuum where the weight matters the most including the beginning.

A sphere has the minimal surface area to volume of all possible closed surfaces. It also has spherical symmetry, which means the curvature, and stress, is the same at every point. I propose a Snowman like staged rocket design. This design would maximize the ratio between the propellent and the dry weight of the rocket. Coupled with the cheapest fuel available (liquid methane or liquid natural gas) the cost of spaceflight can be lowered considerably.

The precise throttleable rocket engines would lift the rocket vertically at lower speeds to minimize the loss due to non-aerodynamic design. At altitudes where the air is thin enough, the rocket would speed up horizontally to achieve orbital velocities.