Some things that can cause   pennies to corrode would include rain, oxygen, acid, other   forms of water besides rain, salts, and pollution. The iron (or other ferrous metal) in the penny causes it rust. If the penny is not made from a ferrous metal (for example iron or steel), then it will NOT … Read more

It is far too cold for humans to live on Neptune, so you would need something that could keep you warm. You would also need food, water, first aid (something similar) and something to do so you wouldn't die of boredom!