wow does anyone see how absolutely ridiculous that is... first of all we do not live in a VACUUM (if i was dieing in space because i didnt have a space suit i would definately want an aluminum mp3 player) second if there was oxygen for it to be exposed to it would not be a VACUUM...some one is really confused, and by the way aluminum is really easy to scratch. if you want to get into chemistry ill tell you that Al2O3 (2 and 3 are subscripts) wich is aluminum oxide (in laymens terms aluminum "rust") is not hard at all, you can actually scratch it with you fingernail...Chemistry 101--aluminum, when exposed to oxygen, forms a protective layer of aluminum oxide, which is much more difficult to scratch than aluminum in a vacuum.