Vogos have a lot of power, they have enough power to blow up a planet and guess what, they did. They blew up Earth, our planet. You wanna know what is even worse, Zaphod Beeblebrox approved the plans thinking that a fan just wanted an autograph. The Vogons have access to billions of other Vogons and ships with supercharged lasers and that is what allows them to blow up worlds. They actually blew up earth for a bypass to be built.