Terraform
From Starfleet Commander
The terraforming feature allows players to add five fields to a planet by spending credits. The credit cost is the current number of fields squared, and then doubled.
The formula is:
2F2
where F is equal to the number of fields a planet currently has.
This feature allows players to increase the number of fields without abandoning the planet and losing all structures and the required colony forming ship in the process.
To use this feature, you must select the planet where you would like to add fields and click on the "Terraform" button found on the Buildings or Home page.