A spaceships tactical/strategic game I can't find anymore?

In there is a number of planets and you have a number of ships on a planet and you can send a number of ships from one planet to another in order to invade it. The number of ships on each planet is increasing and the planets evolve as the number of ships on them increase! There is another player in the game against whom you compete and you win when you defeat all his ships. BTW, you don't control single ships, you just determine how many ships to move from one planet to another.