The Kerbals have conquered the solar system. They think. At least, they're pretty sure that they have almost 90% of it covered. Possibly.

Bored of sending titanic landers and massive rovers to moons and planets, the Kerbal Space Center staff consulted their idea machine; the janitor. "Why not a one of those other glowy orbs in the sky?" KSC immediately began plans for an interstellar ship and consequently fired the janitor because he thought of it first.

Equestria is in for a huge surprise.