Mercury-is made up mostly of iron, with a thin rocky layer. If placed on this planet, the prisoners could be put to work digging up iron, and that iron could be sold and also used to make other prisoners jail cells.

Venus-is made up of nitrogen, carbon monoxide, argon, sulfur dioxide, and water vapor. Venus has vast plains and mountains. because with carbon monoxide, the planet would be unliveable. But with a giant bubble made, the air could be changed, and the prisoners would remain in and only in that bubble.

Mars-is made up mostly of silicate rock, like earth. Mars has many mountains. If placed on this planet, prisoners could carve faces into mountains, much like Mount Rushmore, for work. Mars is liveable in its current state.

Jupiter-is made up mostly of hydrogen and helium. If placed on this planet, prisoners could be put to work making huge bubbles, and a ballon factory. The bubbles would have to be filled with nitrogen, because a planet filled with helium and hydrogen is unliiveable.

Saturn-is made up mostly of hydrogen, helium, methane, and ammonia. If placed on this planet, prisoners could be given gas masks and flame throweres to fight off the ammonia. If the prisoners choose to take off their gas masks or fight each other with their flame throwers, so be it. Let them die.

Uranus-is made up mostly of methane ice. There isn't much we can do to change the temperature of a planet. So if placed here, prisoners could be put to work gathering natural resources, while freezing their tails off suffering for their crimes.

Neptune-is made up mostly of helium, hydrogen, and methane. Like Jupiter, if placed here, prisoners could be put to work making huge bubbles to live in for them and others.