[Suicide Junkie]

I don't remember the Last time I built a sphereworld, but according to my calculations, you could build a sphereworld in two turns.

All it requires is 11 construction ships, plus the application of $5,000,000. (Divided among each resource).

Build 11, 3000/3000/3000 resource bases, then use a $5M set of retroseries to rush build the sphereworld.

Building a sphereworld via the methods below will cost you only $1,800,000 in construction costs.
(40,000 resources per turn)
(40% the price)
(125x less resource storage required)