Well, bad news: Space is really, really different. In particular, moving a vehicle in orbit around Earth is way more complicated than that. But velocity isn’t just speed, it’s speed in a particular direction—in other words, it’s a vector. If an object is moving in a circle, its direction is constantly changing, which means it’s constantly accelerating, even if its speed is constant! The magnitude of the acceleration depends on both the magnitude of the velocity (v), i.e., the speed, and the radius (r) of the circle.