Some of the numbers in the article are confusing to me. Maybe you can clarify. It says at the beginning of the article that it is a 3 billion mile journey. Toward the bottom, it appears to say that Ceres is about three times farther from the sun than the earth is from the sun. This seems like a contradiction.
OK, I’m NOT a Rocket Scientist... but I’ll give it a stab.
It may be distance as a crow flies vs. distance one needs to travel in order to reach an object.
or not.
It depends on where the Earth and Ceres are in their orbits at launch and at arrival. Everything is still moving the whole time, which is why orbital dynamics is tough work. :)